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Høgsbjerg KW, Maae E, Nielsen MH, Stenbygaard L, Pedersen AN, Yates E, Berg M, Lorenzen EL, Jensen I, Josipovic M, Thomsen MS, Offersen BV. Benefit of respiratory gating in the Danish Breast Cancer Group partial breast irradiation trial. Radiother Oncol 2024; 194:110195. [PMID: 38442840 DOI: 10.1016/j.radonc.2024.110195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 12/18/2023] [Accepted: 02/27/2024] [Indexed: 03/07/2024]
Abstract
BACKGROUND AND PURPOSE Partial breast irradiation (PBI)has beenthe Danish Breast Cancer Group(DBCG) standard for selected breast cancer patients since 2016 based onearlyresults from the DBCG PBI trial.During trial accrual, respiratory-gated radiotherapy was introduced in Denmark. This study aims to investigate the effect of respiratory-gating on mean heart dose (MHD). PATIENTS AND METHODS From 2009 to 2016 the DBCG PBI trial included 230 patientswith left-sided breast cancer receiving external beam PBI, 40 Gy/15 fractions/3 weeks.Localization of the tumor bed on the planning CT scan, the use of respiratory-gating, coverage of the clinical target volume (CTV), and doses to organs at risk were collected. RESULTS Respiratory-gating was used in 123 patients (53 %). In 176 patients (77 %) the tumor bed was in the upper and in 54 patients (23 %) in the lower breast quadrants. The median MHD was 0.37 Gy (interquartile range 0.26-0.57 Gy), 0.33 Gy (0.23-0.49 Gy) for respiratory-gating, and 0.49 Gy (0.31-0.70 Gy) for free breathing, p < 0.0001. MHD was < 1 Gy in 206 patients (90 %) and < 2 Gy in 221 patients (96 %). Respiratory-gating led to significantly lower MHD for upper-located, but not for lower-located tumor beds, however, all MHD were low irrespective of respiratory-gating. Respiratory-gating did not improve CTV coverage or lower lung doses. CONCLUSIONS PBI ensured a low MHD for most patients. Adding respiratory-gating further reduced MHD for upper-located but not for lower-located tumor beds but did not influence target coverage or lung doses. Respiratory-gating is no longer DBCG standard for left-sided PBI.
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Affiliation(s)
- Kristine W Høgsbjerg
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Department of Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
| | - Else Maae
- Department of Oncology, Vejle Hospital, University of Southern Denmark, Beriderbakken 4, 7100 Vejle, Denmark.
| | - Mette H Nielsen
- Department of Oncology, Odense University Hospital, Sdr. Boulevard 29, 5000 Odense C, Denmark.
| | - Lars Stenbygaard
- Department of Oncology, Aalborg University Hospital, Hobrovej 18-22, 9000 Aalborg, Denmark.
| | - Anders N Pedersen
- Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.
| | - Esben Yates
- Department of Medical Physics, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
| | - Martin Berg
- Department of Medical Physics, Vejle Hospital, University of Southern Denmark, Beriderbakken 4, Vejle, Denmark.
| | - Ebbe L Lorenzen
- Laboratory of Radiation Physics, Odense University Hospital, Sdr. Boulevard 29, 5000 Odense C, Denmark.
| | - Ingelise Jensen
- Department of Medical Physics, Aalborg University Hospital, Hobrovej 18-22, 9100 Aalborg, Denmark.
| | - Mirjana Josipovic
- Department of Oncology, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark.
| | - Mette S Thomsen
- Department of Medical Physics, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
| | - Birgitte V Offersen
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark; Department of Oncology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
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Shi C, Liang D, Wang H, Zhu Y. High efficiency free-breathing 3D thoracic aorta vessel wall imaging using self-gating image reconstruction. Magn Reson Imaging 2024; 107:80-87. [PMID: 38237694 DOI: 10.1016/j.mri.2024.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 01/14/2024] [Indexed: 01/23/2024]
Abstract
PURPOSE To improve the scan efficiency of thoracic aorta vessel wall imaging using a self-gating (SG)-based motion correction scheme. MATERIALS AND METHODS A slab-selective variable-flip-angle 3D turbo spin-echo (SPACE) sequence was modified to acquire SG signals and imaging data. Cartesian sampling with a tiny golden-step spiral profile ordering was used to obtain the imaging data during the systolic period, and then the image data were subsequently corrected based on the SG signals and binned to different respiratory cycles. Finally, respiratory artifacts were estimated from image-based registration of 3D undersampled respiratory bins that were reconstructed with L1 iterative self-consistent parallel imaging reconstruction (SPIRiT). This method was evaluated in 11 healthy volunteers and compared against conventional diaphragmatic navigator-gated acquisition to assess the feasibility of the proposed framework. RESULTS Results showed that the proposed method achieved image quality comparable to that of conventional diaphragmatic navigator-gated acquisition with an average scan time of 4 min. The sharpness of the vessel wall and the definition of the liver boundary were in good agreement with the navigator-gated acquisition, which took approximately above 8.5 min depend on the respiratory rate. Further valuation of this technique in patients will be conducted to determine its clinical use.
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Affiliation(s)
- Caiyun Shi
- School of Biomedical Engineering, The Fourth Affiliated Hospital, Guangzhou Medical University, Guangzhou, China.
| | - Dong Liang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, Guangdong, China; Medical AI Research Centre, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, Guangdong, China
| | - Haifeng Wang
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, Guangdong, China
| | - Yanjie Zhu
- Paul C. Lauterbur Research Centre for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, Guangdong, China.
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Lau BKF, Dillon O, Vinod SK, O'Brien RT, Reynolds T. Faster and lower dose imaging: evaluating adaptive, constant gantry velocity and angular separation in fast low-dose 4D cone beam CT imaging. Med Phys 2024; 51:1364-1382. [PMID: 37427751 DOI: 10.1002/mp.16585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 05/10/2023] [Accepted: 06/05/2023] [Indexed: 07/11/2023] Open
Abstract
BACKGROUND The adoption of four-dimensional cone beam computed tomography (4DCBCT) for image-guided lung cancer radiotherapy is increasing, especially for hypofractionated treatments. However, the drawbacks of 4DCBCT include long scan times (∼240 s), inconsistent image quality, higher imaging dose than necessary, and streaking artifacts. With the emergence of linear accelerators that can acquire 4DCBCT scans in a short period of time (9.2 s) there is a need to examine the impact that these very fast gantry rotations have on 4DCBCT image quality. PURPOSE This study investigates the impact of gantry velocity and angular separation between x-ray projections on image quality and its implication for fast low-dose 4DCBCT with emerging systems, such as the Varian Halcyon that provide fast gantry rotation and imaging. Large and uneven angular separation between x-ray projections is known to reduce 4DCBCT image quality through increased streaking artifacts. However, it is not known when angular separation starts degrading image quality. The study assesses the impact of constant and adaptive gantry velocity and determines the level when angular gaps impair image quality using state-of-the-art reconstruction methods. METHODS This study considers fast low-dose 4DCBCT acquisitions (60-80 s, 200-projection scans). To assess the impact of adaptive gantry rotations, the angular position of x-ray projections from adaptive 4DCBCT acquisitions from a 30-patient clinical trial were analyzed (referred to as patient angular gaps). To assess the impact of angular gaps, variable and static angular gaps (20°, 30°, 40°) were introduced into evenly separated 200 projections (ideal angular separation). To simulate fast gantry rotations, which are on emerging linacs, constant gantry velocity acquisitions (9.2 s, 60 s, 120 s, 240 s) were simulated by sampling x-ray projections at constant intervals using the patient breathing traces from the ADAPT clinical trial (ACTRN12618001440213). The 4D Extended Cardiac-Torso (XCAT) digital phantom was used to simulate projections to remove patient-specific image quality variables. Image reconstruction was performed using Feldkamp-Davis-Kress (FDK), McKinnon-Bates (MKB), and Motion-Compensated-MKB (MCMKB) algorithms. Image quality was assessed using Structural Similarity-Index-Measure (SSIM), Contrast-to-Noise-Ratio (CNR), Signal-to-Noise-Ratio (SNR), Tissue-Interface-Width-Diaphragm (TIW-D), and Tissue-Interface-Width-Tumor (TIW-T). RESULTS Patient angular gaps and variable angular gap reconstructions produced similar results to ideal angular separation reconstructions, while static angular gap reconstructions produced lower image quality metrics. For MCMKB-reconstructions, average patient angular gaps produced SSIM-0.98, CNR-13.6, SNR-34.8, TIW-D-1.5 mm, and TIW-T-2.0 mm, static angular gap 40° produced SSIM-0.92, CNR-6.8, SNR-6.7, TIW-D-5.7 mm, and TIW-T-5.9 mm and ideal produced SSIM-1.00, CNR-13.6, SNR-34.8, TIW-D-1.5 mm, and TIW-T-2.0 mm. All constant gantry velocity reconstructions produced lower image quality metrics than ideal angular separation reconstructions regardless of the acquisition time. Motion compensated reconstruction (MCMKB) produced the highest contrast images with low streaking artifacts. CONCLUSION Very fast 4DCBCT scans can be acquired provided that the entire scan range is adaptively sampled, and motion-compensated reconstruction is performed. Importantly, the angular separation between x-ray projections within each individual respiratory bin had minimal effect on the image quality of fast low-dose 4DCBCT imaging. The results will assist the development of future 4DCBCT acquisition protocols that can now be achieved in very short time frames with emerging linear accelerators.
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Affiliation(s)
- Benjamin K F Lau
- Faculty of Medicine and Health, Image X Institute, University of Sydney, Sydney, NSW, Australia
| | - Owen Dillon
- Faculty of Medicine and Health, Image X Institute, University of Sydney, Sydney, NSW, Australia
| | - Shalini K Vinod
- Liverpool & Macarthur Cancer Therapy Centres, Liverpool Hospital, Liverpool, New South Wales, Australia
- South Western Sydney Clinical School, The University of New South Wales & Ingham Institute for Applied Medical Research, Liverpool, New South Wales, Australia
| | - Ricky T O'Brien
- Faculty of Medicine and Health, Image X Institute, University of Sydney, Sydney, NSW, Australia
- Medical Radiations, School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Tess Reynolds
- Faculty of Medicine and Health, Image X Institute, University of Sydney, Sydney, NSW, Australia
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Murray V, Siddiq S, Crane C, El Homsi M, Kim TH, Wu C, Otazo R. Movienet: Deep space-time-coil reconstruction network without k-space data consistency for fast motion-resolved 4D MRI. Magn Reson Med 2024; 91:600-614. [PMID: 37849064 PMCID: PMC10842259 DOI: 10.1002/mrm.29892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 10/19/2023]
Abstract
PURPOSE To develop a novel deep learning approach for 4D-MRI reconstruction, named Movienet, which exploits space-time-coil correlations and motion preservation instead of k-space data consistency, to accelerate the acquisition of golden-angle radial data and enable subsecond reconstruction times in dynamic MRI. METHODS Movienet uses a U-net architecture with modified residual learning blocks that operate entirely in the image domain to remove aliasing artifacts and reconstruct an unaliased motion-resolved 4D image. Motion preservation is enforced by sorting the input image and reference for training in a linear motion order from expiration to inspiration. The input image was collected with a lower scan time than the reference XD-GRASP image used for training. Movienet is demonstrated for motion-resolved 4D MRI and motion-resistant 3D MRI of abdominal tumors on a therapeutic 1.5T MR-Linac (1.5-fold acquisition acceleration) and diagnostic 3T MRI scanners (2-fold and 2.25-fold acquisition acceleration for 4D and 3D, respectively). Image quality was evaluated quantitatively and qualitatively by expert clinical readers. RESULTS The reconstruction time of Movienet was 0.69 s (4 motion states) and 0.75 s (10 motion states), which is substantially lower than iterative XD-GRASP and unrolled reconstruction networks. Movienet enables faster acquisition than XD-GRASP with similar overall image quality and improved suppression of streaking artifacts. CONCLUSION Movienet accelerates data acquisition with respect to compressed sensing and reconstructs 4D images in less than 1 s, which would enable an efficient implementation of 4D MRI in a clinical setting for fast motion-resistant 3D anatomical imaging or motion-resolved 4D imaging.
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Affiliation(s)
- Victor Murray
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Syed Siddiq
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Christopher Crane
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Maria El Homsi
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Tae-Hyung Kim
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Can Wu
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ricardo Otazo
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
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Morales MA, Assana S, Cai X, Chow K, Haji-Valizadeh H, Sai E, Tsao C, Matos J, Rodriguez J, Berg S, Whitehead N, Pierce P, Goddu B, Manning WJ, Nezafat R. An inline deep learning based free-breathing ECG-free cine for exercise cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2022; 24:47. [PMID: 35948936 PMCID: PMC9367083 DOI: 10.1186/s12968-022-00879-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 07/21/2022] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Exercise cardiovascular magnetic resonance (Ex-CMR) is a promising stress imaging test for coronary artery disease (CAD). However, Ex-CMR requires accelerated imaging techniques that result in significant aliasing artifacts. Our goal was to develop and evaluate a free-breathing and electrocardiogram (ECG)-free real-time cine with deep learning (DL)-based radial acceleration for Ex-CMR. METHODS A 3D (2D + time) convolutional neural network was implemented to suppress artifacts from aliased radial cine images. The network was trained using synthetic real-time radial cine images simulated using breath-hold, ECG-gated segmented Cartesian k-space data acquired at 3 T from 503 patients at rest. A prototype real-time radial sequence with acceleration rate = 12 was used to collect images with inline DL reconstruction. Performance was evaluated in 8 healthy subjects in whom only rest images were collected. Subsequently, 14 subjects (6 healthy and 8 patients with suspected CAD) were prospectively recruited for an Ex-CMR to evaluate image quality. At rest (n = 22), standard breath-hold ECG-gated Cartesian segmented cine and free-breathing ECG-free real-time radial cine images were acquired. During post-exercise stress (n = 14), only real-time radial cine images were acquired. Three readers evaluated residual artifact level in all collected images on a 4-point Likert scale (1-non-diagnostic, 2-severe, 3-moderate, 4-minimal). RESULTS The DL model substantially suppressed artifacts in real-time radial cine images acquired at rest and during post-exercise stress. In real-time images at rest, 89.4% of scores were moderate to minimal. The mean score was 3.3 ± 0.7, representing increased (P < 0.001) artifacts compared to standard cine (3.9 ± 0.3). In real-time images during post-exercise stress, 84.6% of scores were moderate to minimal, and the mean artifact level score was 3.1 ± 0.6. Comparison of left-ventricular (LV) measures derived from standard and real-time cine at rest showed differences in LV end-diastolic volume (3.0 mL [- 11.7, 17.8], P = 0.320) that were not significantly different from zero. Differences in measures of LV end-systolic volume (7.0 mL [- 1.3, 15.3], P < 0.001) and LV ejection fraction (- 5.0% [- 11.1, 1.0], P < 0.001) were significant. Total inline reconstruction time of real-time radial images was 16.6 ms per frame. CONCLUSIONS Our proof-of-concept study demonstrated the feasibility of inline real-time cine with DL-based radial acceleration for Ex-CMR.
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Affiliation(s)
- Manuel A Morales
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Salah Assana
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Xiaoying Cai
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
- Siemens Medical Solutions USA, Inc, Chicago, IL, USA
| | - Kelvin Chow
- Siemens Medical Solutions USA, Inc, Chicago, IL, USA
| | - Hassan Haji-Valizadeh
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Eiryu Sai
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Connie Tsao
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Jason Matos
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Jennifer Rodriguez
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Sophie Berg
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Neal Whitehead
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Patrick Pierce
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Beth Goddu
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
| | - Warren J Manning
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA
- Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - Reza Nezafat
- Department of Medicine (Cardiovascular Division), Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave., Boston, MA, 02215, USA.
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Thomas MA, Meier JG, Mawlawi OR, Sun P, Pan T. Impact of acquisition time and misregistration with CT on data-driven gated PET. Phys Med Biol 2022; 67:10.1088/1361-6560/ac5f73. [PMID: 35313286 PMCID: PMC9128538 DOI: 10.1088/1361-6560/ac5f73] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 03/21/2022] [Indexed: 11/11/2022]
Abstract
Objective. Data-driven gating (DDG) can address patient motion issues and enhance PET quantification but suffers from increased image noise from utilization of <100% of PET data. Misregistration between DDG-PET and CT may also occur, altering the potential benefits of gating. Here, the effects of PET acquisition time and CT misregistration were assessed with a combined DDG-PET/DDG-CT technique.Approach. In the primary PET bed with lesions of interest and likely respiratory motion effects, PET acquisition time was extended to 12 min and a low-dose cine CT was acquired to enable DDG-CT. Retrospective reconstructions were created for both non-gated (NG) and DDG-PET using 30 s to 12 min of PET data. Both the standard helical CT and DDG-CT were used for attenuation correction of DDG-PET data. SUVmax, SUVpeak, and CNR were compared for 45 lesions in the liver and lung from 27 cases.Main results. For both NG-PET (p= 0.0041) and DDG-PET (p= 0.0028), only the 30 s acquisition time showed clear SUVmaxbias relative to the 3 min clinical standard. SUVpeakshowed no bias at any change in acquisition time. DDG-PET alone increased SUVmaxby 15 ± 20% (p< 0.0001), then was increased further by an additional 15 ± 29% (p= 0.0007) with DDG-PET/CT. Both 3 min and 6 min DDG-PET had lesion CNR statistically equivalent to 3 min NG-PET, but then increased at 12 min by 28 ± 48% (p= 0.0022). DDG-PET/CT at 6 min had comparable counts to 3 min NG-PET, but significantly increased CNR by 39 ± 46% (p< 0.0001).Significance. 50% counts DDG-PET did not lead to inaccurate or biased SUV-increased SUV resulted from gating. Improved registration from DDG-CT was equally as important as motion correction with DDG-PET for increasing SUV in DDG-PET/CT. Lesion detectability could be significantly improved when DDG-PET used equivalent counts to NG-PET, but only when combined with DDG-CT in DDG-PET/CT.
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Affiliation(s)
- M. Allan Thomas
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX 77030
| | - Joseph G. Meier
- Department of Medical Physics, University of Wisconsin, Madison, WI 53726
| | - Osama R. Mawlawi
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX 77030
| | - Peng Sun
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX 77030
| | - Tinsu Pan
- Department of Imaging Physics, UT MD Anderson Cancer Center, Houston, TX 77030
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Suzuki K, Takehara Y, Sakata M, Kawate M, Ohishi N, Sugiyama K, Akai T, Suzuki Y, Sugiyama M, Kawamura T, Morita Y, Kikuchi H, Hiramatsu Y, Yamamoto M, Nasu H, Johnson K, Wieben O, Kurachi K, Takeuchi H. Daikenchuto increases blood flow in the superior mesenteric artery in humans: A comparison study between four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction magnetic resonance imaging and Doppler ultrasound. PLoS One 2021; 16:e0245878. [PMID: 33503053 PMCID: PMC7840032 DOI: 10.1371/journal.pone.0245878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 01/07/2021] [Indexed: 11/18/2022] Open
Abstract
Respiratory-gated four-dimensional phase-contrast vastly undersampled isotropic projection reconstruction (4D PC-VIPR) is magnetic resonance (MR) imaging technique that enables analysis of vascular morphology and hemodynamics in a single examination using cardiac phase resolved 3D phase-contrast magnetic resonance imaging. The present study aimed to assess the usefulness of 4D PC-VIPR for the superior mesenteric artery (SMA) flowmetry before and after flow increase was induced by the herbal medicine Daikenchuto (TJ-100) by comparing it with Doppler ultrasound (DUS) as a current standard. Twenty healthy volunteers were enrolled in this prospective single-arm study. The peak cross-sectionally averaged velocity was measured by 4D PC-VIPR, peak velocity was measured by DUS, and flow volume (FV) of SMA and aorta were measured by 4D PC-VIPR and DUS 25 min before and after the peroral administration of TJ-100. The peak cross-sectionally averaged velocity, peak velocity, and FV of SMA measured by 4D PC-VIPR and DUS significantly increased after administration of TJ-100 (4D PC-VIPR: the peak cross-sectionally averaged velocity; p = 0.004, FV; p = 0.035, DUS: the peak velocity; p = 0.003, FV; p = 0.010). Furthermore, 4D PC-VIPR can analyze multiple blood vessels simultaneously. The ratio of the SMA FV to the aorta, before and after oral administration on the 4D PC-VIPR test also increased (p = 0.015). The rate of change assessed by 4D PC-VIPR and DUS were significantly correlated (the peak cross-sectionally averaged velocity and peak velocity: r = 0.650; p = 0.005, FV: r = 0.659; p = 0.004). Retrospective 4D PC-VIPR was a useful modality for morphological and hemodynamic analysis of SMA.
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Affiliation(s)
- Katsunori Suzuki
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yasuo Takehara
- Department of Fundamental Development for Advanced Low Invasive Diagnostic Imaging, Nagoya University, Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Mayu Sakata
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Masanori Kawate
- Department of Radiology, Hamamatsu University Hospital, Hamamatsu, Shizuoka, Japan
| | - Naoki Ohishi
- Department of Radiology, Hamamatsu University Hospital, Hamamatsu, Shizuoka, Japan
| | - Kosuke Sugiyama
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Toshiya Akai
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yuhi Suzuki
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Masataka Sugiyama
- Department of Fundamental Development for Advanced Low Invasive Diagnostic Imaging, Nagoya University, Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Takafumi Kawamura
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yoshifumi Morita
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hirotoshi Kikuchi
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Yoshihiro Hiramatsu
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Masayoshi Yamamoto
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Hatsuko Nasu
- Department of Diagnostic Radiology & Nuclear Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
| | - Kevin Johnson
- Department of Medical Physics, University of Wisconsin, Madison, WI, United States of America
- Department of Radiology, University of Wisconsin, Madison, WI, United States of America
| | - Oliver Wieben
- Department of Medical Physics, University of Wisconsin, Madison, WI, United States of America
- Department of Radiology, University of Wisconsin, Madison, WI, United States of America
| | - Kiyotaka Kurachi
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
- * E-mail:
| | - Hiroya Takeuchi
- Second Department of Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
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Zhang D, Pretorius PH, Ghaly M, Zhang Q, King MA, Mok GSP. Evaluation of different respiratory gating schemes for cardiac SPECT. J Nucl Cardiol 2020; 27:634-647. [PMID: 30088195 DOI: 10.1007/s12350-018-1392-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/17/2018] [Indexed: 11/26/2022]
Abstract
BACKGROUND Respiratory gating reduces motion blurring in cardiac SPECT. Here we aim to evaluate the performance of three respiratory gating strategies using a population of digital phantoms with known truth and clinical data. METHODS We analytically simulated 60 projections for 10 XCAT phantoms with 99mTc-sestamibi distributions using three gating schemes: equal amplitude gating (AG), equal count gating (CG), and equal time gating (TG). Clinical list-mode data for 10 patients who underwent 99mTc-sestamibi scans were also processed using the 3 gating schemes. Reconstructed images in each gate were registered to a reference gate, averaged and reoriented to generate the polar plots. For simulations, image noise, relative difference (RD) of averaged count for each of the 17 segment, and relative defect size difference (RSD) were analyzed. For clinical data, image intensity profile and FWHM were measured across the left ventricle wall. RESULTS For simulations, AG and CG methods showed significantly lower RD and RSD compared to TG, while noise variation was more non-uniform through different gates for AG. In the clinical study, AG and CG had smaller FWHM than TG. CONCLUSIONS AG and CG methods show better performance for motion reduction and are recommended for clinical respiratory gating SPECT implementation.
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Affiliation(s)
- Duo Zhang
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Taipa, Macau SAR, China
- Department of Radiology, University of Massachusetts Medical School, Worcester, USA
| | - P Hendrik Pretorius
- Department of Radiology, University of Massachusetts Medical School, Worcester, USA
| | - Michael Ghaly
- The Russell H Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD, USA
- Radiopharmaceutical Imaging and Dosimetry (RAPID), LLC, Baltimore, MD, USA
| | - Qi Zhang
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Taipa, Macau SAR, China
| | - Michael A King
- Department of Radiology, University of Massachusetts Medical School, Worcester, USA
| | - Greta S P Mok
- Biomedical Imaging Laboratory (BIG), Department of Electrical and Computer Engineering, Faculty of Science and Technology, University of Macau, Taipa, Macau SAR, China.
- Department of Radiology, University of Massachusetts Medical School, Worcester, USA.
- Faculty of Health Sciences, University of Macau, Taipa, Macau SAR, China.
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9
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Blocker SJ, Holbrook MD, Mowery YM, Sullivan DC, Badea CT. The impact of respiratory gating on improving volume measurement of murine lung tumors in micro-CT imaging. PLoS One 2020; 15:e0225019. [PMID: 32097413 PMCID: PMC7041814 DOI: 10.1371/journal.pone.0225019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 01/22/2020] [Indexed: 02/01/2023] Open
Abstract
Small animal imaging has become essential in evaluating new cancer therapies as they are translated from the preclinical to clinical domain. However, preclinical imaging faces unique challenges that emphasize the gap between mouse and man. One example is the difference in breathing patterns and breath-holding ability, which can dramatically affect tumor burden assessment in lung tissue. As part of a co-clinical trial studying immunotherapy and radiotherapy in sarcomas, we are using micro-CT of the lungs to detect and measure metastases as a metric of disease progression. To effectively utilize metastatic disease detection as a metric of progression, we have addressed the impact of respiratory gating during micro-CT acquisition on improving lung tumor detection and volume quantitation. Accuracy and precision of lung tumor measurements with and without respiratory gating were studied by performing experiments with in vivo images, simulations, and a pocket phantom. When performing test-retest studies in vivo, the variance in volume calculations was 5.9% in gated images and 15.8% in non-gated images, compared to 2.9% in post-mortem images. Sensitivity of detection was examined in images with simulated tumors, demonstrating that reliable sensitivity (true positive rate (TPR) ≥ 90%) was achievable down to 1.0 mm3 lesions with respiratory gating, but was limited to ≥ 8.0 mm3 in non-gated images. Finally, a clinically-inspired "pocket phantom" was used during in vivo mouse scanning to aid in refining and assessing the gating protocols. Application of respiratory gating techniques reduced variance of repeated volume measurements and significantly improved the accuracy of tumor volume quantitation in vivo.
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Affiliation(s)
- S. J. Blocker
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - M. D. Holbrook
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Y. M. Mowery
- Department of Radiation Oncology, Duke Cancer Institute, Durham, North Carolina, United States of America
| | - D. C. Sullivan
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - C. T. Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
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10
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Hysinger EB, Bates AJ, Higano NS, Benscoter D, Fleck RJ, Hart CK, Burg G, De Alarcon A, Kingma PS, Woods JC. Ultrashort Echo-Time MRI for the Assessment of Tracheomalacia in Neonates. Chest 2019; 157:595-602. [PMID: 31862439 DOI: 10.1016/j.chest.2019.11.034] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 11/22/2019] [Accepted: 11/25/2019] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Bronchoscopy is the gold standard for evaluating tracheomalacia; however, reliance on an invasive procedure limits understanding of normal airway dynamics. Self-gated ultrashort echo-time MRI (UTE MRI) can assess tracheal dynamics but has not been rigorously evaluated. METHODS This study was a validation of UTE MRI diagnosis of tracheomalacia in neonates using bronchoscopy as the gold standard. Bronchoscopies were reviewed for the severity and location of tracheomalacia based on standardized criteria. The percent change in cross-sectional area (CSA) of the trachea between end-inspiration and end-expiration was determined by UTE MRI, and receiver-operating curves were used to determine the optimal cutoff values to predict tracheomalacia and determine positive and negative predictive values. RESULTS Airway segments with tracheomalacia based on bronchoscopy had a more than threefold change in CSA measured from UTE MRI (54.4 ± 56.1% vs 14.8 ± 19.5%; P < .0001). UTE MRI correlated moderately with bronchoscopy for tracheomalacia severity (ρ = 0.39; P = .0001). Receiver-operating curves, however, showed very good ability of UTE MRI to identify tracheomalacia (area under the curve, 0.78). A "loose" definition (> 20% change in CSA) of tracheomalacia had good sensitivity (80%) but low specificity (64%) for identifying tracheomalacia based on UTE MRI, whereas a "strict" definition (> 40% change in CSA) was poorly sensitive (48%) but highly specific (93%). CONCLUSIONS Self-gated UTE MRI can noninvasively assess tracheomalacia in neonates without sedation, ionizing radiation, or increased risk. This technique overcomes major limitations of other diagnostic modalities and may be suitable for longitudinal population studies of tracheal dynamics.
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Affiliation(s)
- Erik B Hysinger
- Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
| | - Alister J Bates
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Nara S Higano
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Dan Benscoter
- Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Robert J Fleck
- Department of Radiology, University of Cincinnati, College of Medicine, Cincinnati, OH
| | - Catherine K Hart
- Department of Otolaryngology, University of Cincinnati, College of Medicine, Cincinnati, OH; Division of Pediatric Otolaryngology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Gregory Burg
- Department of Pediatrics, University of Pittsburgh, School of Medicine, Pittsburgh, PA; Division of Pulmonary Medicine, Children's Hospital of Pittsburgh, Pittsburgh, PA
| | - Alessandro De Alarcon
- Department of Otolaryngology, University of Cincinnati, College of Medicine, Cincinnati, OH; Division of Pediatric Otolaryngology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Paul S Kingma
- Department of Pediatrics, University of Cincinnati, College of Medicine, Cincinnati, OH; Division of Neonatology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Jason C Woods
- Departments of Pediatrics & Radiology, University of Cincinnati, College of Medicine, Cincinnati, OH; Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
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Abstract
Cardiac PET provides high sensitivity and high negative predictive value in the diagnosis of coronary artery disease and cardiomyopathies. Cardiac, respiratory as well as bulk patient motion have detrimental effects on thoracic PET imaging, in particular on cardiovascular PET imaging where the motion can affect the PET images quantitatively as well as qualitatively. Gating can ameliorate the unfavorable impact of motion additionally enabling evaluation of left ventricular systolic function. In this article, the authors review the recent advances in gating approaches and highlight the advances in data-driven approaches, which hold promise in motion detection without the need for complex hardware setup.
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Affiliation(s)
| | - Jacek Kwiecinski
- Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA; British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Piotr J Slomka
- Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA.
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12
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Deng Z, Pang J, Lao Y, Bi X, Wang G, Chen Y, Fenchel M, Tuli R, Li D, Yang W, Fan Z. A post-processing method based on interphase motion correction and averaging to improve image quality of 4D magnetic resonance imaging: a clinical feasibility study. Br J Radiol 2019; 92:20180424. [PMID: 30604622 PMCID: PMC6541178 DOI: 10.1259/bjr.20180424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 10/26/2018] [Accepted: 12/11/2018] [Indexed: 11/05/2022] Open
Abstract
METHODS: Nine patients (seven pancreas, one liver, and one lung) were recruited. 4D-MRI was performed using two prototype k-space sorted techniques, stack-of-stars (SOS) and koosh-ball (KB) acquisitions. Post-processing using MoCoAve was implemented for both methods. Image quality score, apparent SNR (aSNR), sharpness, motion trajectory and standard deviation (σ_GTV) of the gross tumor volumes were compared between original and MoCoAve image sets. RESULTS: All subjects successfully underwent 4D-MRI scans and MoCoAve was performed on all data sets. Significantly higher image quality scores (2.64 ± 0.39 vs 1.18 ± 0.34, p = 0.001) and aSNR (37.6 ± 15.3 vs 18.1 ± 5.7, p = 0.001) was observed in the MoCoAve images when compared to the original images. High correlation in tumor motion trajectories in the superoinferior direction (SI: 0.91 ± 0.08) and weaker in the anteroposterior (AP: 0.51 ± 0.44) and mediolateral (ML: 0.37 ± 0.23) directions, similar image sharpness (0.367 ± 0.068 vs 0.369 ± 0.072, p = 0.805), and minimal average absolute difference (0.47 ± 0.34 mm) of the motion trajectory profiles was found between the two image sets. The σ_GTV in pancreas patients was significantly (p = 0.039) lower in MoCoAve images (1.48 ± 1.35 cm3) than in the original images (2.17 ± 1.31 cm3). CONCLUSION: MoCoAve using interphase motion correction and averaging has shown promise as a post-processing method for improving k-space sorted (SOS and KB) 4D-MRI image quality in thoracic and abdominal cancer patients. ADVANCES IN KNOWLEDGE: The proposed method is an image based post-processing method that could be applied to many k-space sorted 4D-MRI methods for improved image quality and signal-to-noise ratio while preserving image sharpness and respiratory motion fidelity. It is a useful technique for the radiotherapy planning community who are interested in using 4D-MRI but aren't satisfied with their current MR image quality.
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Affiliation(s)
- Zixin Deng
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | | | - Yi Lao
- Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - Xiaoming Bi
- MR R&D, Siemens Healthineers, Los Angeles, CA, USA
| | - Guan Wang
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | - Yuhua Chen
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA, USA
| | | | - Richard Tuli
- Department of Radiation Oncology, Cedars Sinai Medical Center, Los Angeles, CA, USA
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Vaniqui A, van der Heyden B, Almeida IP, Schyns LEJR, van Hoof SJ, Verhaegen F. On the determination of planning target margins due to motion for mice lung tumours using a four-dimensional MOBY phantom. Br J Radiol 2019; 92:20180445. [PMID: 30004793 PMCID: PMC6541181 DOI: 10.1259/bjr.20180445] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/05/2018] [Accepted: 07/06/2018] [Indexed: 12/21/2022] Open
Abstract
OBJECTIVE: This work aims to analyse the effect of respiratory motion on optimal irradiation margins for murine lung tumour models. METHODS: Four-dimensional mathematical phantoms with different lung tumour locations affected by respiratory motion were created. Two extreme breathing curves were adopted and divided into time-points. Each time-point was loaded in a treatment planning system and Monte Carlo (MC) dose calculations were performed for a 360° arc plan. A time-resolved dose was derived, considering the gantry rotation and the breathing motion. Radiotherapy metrics were derived to assess the final treatment plans. An interpolation function was investigated to reduce calculation cost. RESULTS: The effect of respiratory motion on the treatment plan quality is strongly dependent on the breathing pattern and the tumour position. Tumours located closer to the diaphragm required a compromise between tumour conformity and healthy tissue damage. A recipe, which considers collimator size, was proposed to derive tumour margins and spare the organs at risk (OARs) by respecting constraints on user-defined metrics. CONCLUSION: It is recommended to add a target margin, especially on sites where movement is substantial. A simple recipe to derive tumour margins was developed. ADVANCES IN KNOWLEDGE: This work is a first step towards a standard planning target volume concept in pre-clinical radiotherapy.
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Affiliation(s)
- Ana Vaniqui
- Department of Radiation Oncology (MAASTRO), GROW—School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Brent van der Heyden
- Department of Radiation Oncology (MAASTRO), GROW—School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Isabel P Almeida
- Department of Radiation Oncology (MAASTRO), GROW—School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Lotte EJR Schyns
- Department of Radiation Oncology (MAASTRO), GROW—School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | | | - Frank Verhaegen
- Department of Radiation Oncology (MAASTRO), GROW—School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, The Netherlands
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14
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Yasui K, Shimomura A, Toshito T, Tanaka K, Ueki K, Muramatsu R, Katsurada M, Hayashi N, Ogino H. A quality assurance for respiratory gated proton irradiation with range modulation wheel. J Appl Clin Med Phys 2019; 20:258-264. [PMID: 30597762 PMCID: PMC6333132 DOI: 10.1002/acm2.12526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 11/07/2018] [Accepted: 12/03/2018] [Indexed: 12/15/2022] Open
Abstract
The purpose of this study was to provide periodic quality assurance (QA) methods for respiratory-gated proton beam with a range modulation wheel (RMW) and to clarify the characteristics and long-term stability of the respiratory-gated proton beam. A two-dimensional detector array and a solid water phantom were used to measure absolute dose, spread-out Bragg peak (SOBP) width and proton range for monthly QA. SOBP width and proton range were measured using an oblique incidence beam to the lateral side of a solid water phantom and compared between with and without a gating proton beam. To measure the delay time of beam-on/off for annual QA, we collected the beam-on/off signals and the dose monitor-detected pulse. We analyzed the results of monthly QA over a 15-month period and investigated the delay time by machine signal analysis. The dose deviations at proximal, SOBP center and distal points were -0.083 ± 0.25%, 0.026 ± 0.20%, and -0.083 ± 0.35%, respectively. The maximum dose deviation between with and without respiratory gating was -0.95% at the distal point and other deviations were within ±0.5%. Proximal and SOBP center doses showed the same trend over a 15-month period. Delay times of beam-on/off for 200 MeV/SOBP 16 cm were 140.5 ± 0.8 ms and 22.3 ± 13.0 ms, respectively. Delay times for 160 MeV/SOBP 10 cm were 167.5 ± 15.1 ms and 19.1 ± 9.8 ms. Our beam delivery system with the RMW showed sufficient stability for respiratory-gated proton therapy and the system did not show dependency on the energy and the respiratory wave form. The delay times of beam-on/off were within expectations. The proposed QA methods will be useful for managing the quality of respiratory-gated proton beams and other beam delivery systems.
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Affiliation(s)
- Keisuke Yasui
- Faculty of Radiological TechnologySchool of Health SciencesFujita Health UniversityToyoakeAichiJapan
| | - Akira Shimomura
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
| | - Toshiyuki Toshito
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
| | - Kenichiro Tanaka
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
| | - Kumiko Ueki
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
| | - Rie Muramatsu
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
| | - Masaki Katsurada
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
| | - Naoki Hayashi
- Faculty of Radiological TechnologySchool of Health SciencesFujita Health UniversityToyoakeAichiJapan
| | - Hiroyuki Ogino
- Nagoya Proton Therapy CenterNagoya City West Medical CenterNagoyaAichiJapan
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15
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Mizuno H, Saito O, Tajiri M, Kimura T, Kuroiwa D, Shirai T, Inaniwa T, Fukahori M, Miki K, Fukuda S. Commissioning of a respiratory gating system involving a pressure sensor in carbon-ion scanning radiotherapy. J Appl Clin Med Phys 2019; 20:37-42. [PMID: 30387271 PMCID: PMC6333131 DOI: 10.1002/acm2.12463] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/29/2018] [Accepted: 08/31/2018] [Indexed: 11/06/2022] Open
Abstract
This study reports the commissioning methodology and results of a respiratory gating system [AZ - 733 V/733 VI (Anzai Medical Co., Japan)] using a pressure sensor in carbon-ion scanning radiotherapy. Commissioning includes choosing a location and method for pressure sensor installation, delay time measurement of the system, and the final flow test. Additionally, we proposed a methodology for the determination of a threshold level of generating an on/off gate for the beam to the respiratory waveform, which is important for clinical application. Regarding the location and method for installation of the pressure sensor, the actual person's abdomen, back of the body position, and supine/prone positioning were checked. By comparing the motion between the pressure sensor output and the reference LED sensor motion, the chest rear surface was shown to be unsuitable for the sensor installation, due to noise in the signal caused by the cardiac beat. Regarding delay time measurement of the system, measurements were performed for the following four steps: (a). Actual motion to wave signal generation; (b). Wave signal to gate signal generation; (c). Gate signal to beam on/off signal generation; (d). Beam on/off signal to the beam irradiation. The total delay time measured was 46 ms (beam on)/33 ms (beam off); these were within the prescribed tolerance time (<100 ms). Regarding the final flow test, an end-to-end test was performed with a patient verification system using an actual carbon-ion beam; the respiratory gating irradiation was successfully performed, in accordance with the intended timing. Finally, regarding the method for determining the threshold level of the gate generation of the respiration waveform, the target motion obtained from 4D-CT was assumed to be correlated with the waveform obtained from the pressure sensor; it was used to determine the threshold value in amplitude direction.
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Affiliation(s)
| | - Osami Saito
- National institute of Radiological Sciences, QSTChibaJapan
| | - Minoru Tajiri
- National institute of Radiological Sciences, QSTChibaJapan
| | - Taku Kimura
- National institute of Radiological Sciences, QSTChibaJapan
| | - Daigo Kuroiwa
- National institute of Radiological Sciences, QSTChibaJapan
| | | | - Taku Inaniwa
- National institute of Radiological Sciences, QSTChibaJapan
| | - Mai Fukahori
- National institute of Radiological Sciences, QSTChibaJapan
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Mendes Pereira L, Wech T, Weng AM, Kestler C, Veldhoen S, Bley TA, Köstler H. UTE-SENCEFUL: first results for 3D high-resolution lung ventilation imaging. Magn Reson Med 2018; 81:2464-2473. [PMID: 30393947 DOI: 10.1002/mrm.27576] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/27/2018] [Accepted: 10/01/2018] [Indexed: 02/05/2023]
Abstract
PURPOSE This study aimed to develop a 3D MRI technique to assess lung ventilation in free-breathing and without the administration of contrast agent. METHODS A 3D-UTE sequence with a koosh ball trajectory was developed for a 3 Tesla scanner. An oversampled k-space was acquired, and the direct current signal from the k-space center was used as a navigator to sort the acquired data into 8 individual breathing phases. Gradient delays were corrected, and iterative SENSE was used to reconstruct the individual timeframes. Subsequently, the signal changes caused by motion were eliminated using a 3D image registration technique, and ventilation-weighted maps were created by analyzing the signal changes in the lung tissue. Six healthy volunteers and 1 patient with lung cancer were scanned with the new 3D-UTE and the standard 2D technique. Image quality and quantitative ventilation values were compared between both methods. RESULTS UTE-based self-gated noncontrast-enhanced functional lung (SENCEFUL) MRI provided a time-resolved reconstruction of the breathing motion, with a 49% increase of the SNR. Ventilation quantification for healthy subjects was in statistical agreement with 2D-SENCEFUL and the literature, with a mean value of 0.11 ± 0.08 mL/mL for the whole lung. UTE-SENCEFUL was able to visualize and quantify ventilation deficits in a patient with lung tumor that were not properly depicted by 2D-SENCEFUL. CONCLUSION UTE-SENCEFUL represents a robust MRI method to assess both morphological and functional information of the lungs in 3D. When compared to the 2D approach, 3D-UTE offered ventilation maps with higher resolution, improved SNR, and reduced ventilation artifacts.
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Affiliation(s)
- L Mendes Pereira
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
| | - T Wech
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
| | - A M Weng
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
| | - C Kestler
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
| | - S Veldhoen
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
| | - T A Bley
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
| | - H Köstler
- Department of Diagnostic and Interventional Radiology, University of Würzburg, Germany
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Yang W, Fan Z, Deng Z, Pang J, Bi X, Fraass BA, Sandler H, Li D, Tuli R. Novel 4D-MRI of tumor infiltrating vasculature: characterizing tumor and vessel volume motion for selective boost volume definition in pancreatic radiotherapy. Radiat Oncol 2018; 13:191. [PMID: 30285889 PMCID: PMC6167784 DOI: 10.1186/s13014-018-1139-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 09/24/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Pancreatic ductal adenocarcinoma has dismal prognosis. Most patients receive radiation therapy (RT), which is complicated by respiration induced organ motion in upper abdomen. The purpose of this study is to report our early clinical experience in a novel self-gated k-space sorted four-dimensional magnetic resonance imaging (4D-MRI) with slab-selective (SS) excitation to highlight tumor infiltrating blood vessels for pancreatic RT. METHODS Ten consecutive patients with borderline resectable or locally advanced pancreatic cancer were recruited to the study. Non-contrast 4D-MRI with and without slab-selective excitation and 4D-CT with delay contrast were performed on all patients. Vessel-tissue CNR were calculated for aorta and critical vessels (superior mesenteric artery or superior mesenteric vein) encompassed by tumor. Respiratory motion trajectories for tumor, as well as involved vessels were analyzed on SS-4D-MRI. Intra-class cross correlation (ICC) between tumor volume and involved vessels were calculated. RESULTS Among all 4D imaging modalities evaluated, SS-4D-MRI sampling trajectory results in images with highest vessel-tissue CNR comparing to non-slab-selective 4D-MRI and 4D-CT for all patients studied. Average (±standard deviation) CNR for involved vessels are 13.1 ± 8.4 and 3.2 ± 2.7 for SS-4D-MRI and 4D-CT, respectively. The ICC factors comparing tumor and involved vessels motion trajectories are 0.93 ± 0.10, 0.65 ± 0.31 and 0.77 ± 0.23 for superior-inferior, anterior-posterior and medial-lateral directions respectively. CONCLUSIONS A novel 4D-MRI sequence based on 3D-radial sampling and slab-selective excitation has been assessed for pancreatic cancer patients. The non-contrast 4D-MRI images showed significantly better contrast to noise ratio for the vessels that limit tumor resectability compared to 4D-CT with delayed contrast. The sequence has great potential in accurately defining both the tumor and boost volume margins for pancreas RT with simultaneous integrated boost.
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Affiliation(s)
- Wensha Yang
- Department of Radiation Oncology, Cedars Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA USA
| | - Zhaoyang Fan
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA USA
| | - Zixin Deng
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA USA
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA USA
| | | | | | - Benedick A Fraass
- Department of Radiation Oncology, Cedars Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Howard Sandler
- Department of Radiation Oncology, Cedars Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
| | - Debiao Li
- Department of Biomedical Sciences, Biomedical Imaging Research Institute, Cedars Sinai Medical Center, Los Angeles, CA USA
| | - Richard Tuli
- Department of Radiation Oncology, Cedars Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048 USA
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Feng T, Wang J, Sun Y, Zhu W, Dong Y, Li H. Self-Gating: An Adaptive Center-of-Mass Approach for Respiratory Gating in PET. IEEE Trans Med Imaging 2018; 37:1140-1148. [PMID: 29727277 DOI: 10.1109/tmi.2017.2783739] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The goal is to develop an adaptive center-of-mass (COM)-based approach for device-less respiratory gating of list-mode positron emission tomography (PET) data. Our method contains two steps. The first is to automatically extract an optimized respiratory motion signal from the list-mode data during acquisition. The respiratory motion signal was calculated by tracking the location of COM within a volume of interest (VOI). The signal prominence (SP) was calculated based on Fourier analysis of the signal. The VOI was adaptively optimized to maximize SP. The second step is to automatically correct signal-flipping effects. The sign of the signal was determined based on the assumption that the average patient spends more time during expiration than inspiration. To validate our methods, thirty-one 18F-FDG patient scans were included in this paper. An external device-based signal was used as the gold standard, and the correlation coefficient of the data-driven signal with the device-based signal was measured. Our method successfully extracted respiratory signal from 30 out of 31 datasets. The failure case was due to lack of uptake in the field of view. Moreover, our sign determination method obtained correct results for all scans excluding the failure case. Quantitatively, the proposed signal extraction approach achieved a median correlation of 0.85 with the device-based signal. Gated images using optimized data-driven signal showed improved lesion contrast over static image and were comparable to those using device-based signal. We presented a new data-driven method to automatically extract respiratory motion signal from list-mode PET data by optimizing VOI for COM calculation, as well as determine motion direction from signal asymmetry. Successful application of the proposed method on most clinical datasets and comparison with device-based signal suggests its potential of serving as an alternative to external respiratory monitors.
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Krebill C. Application of the BLADE Sequence in Upper Abdominal MR Imaging. Radiol Technol 2018; 89:495-497. [PMID: 29793909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
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Edmunds DM, Gothard L, Khabra K, Kirby A, Madhale P, McNair H, Roberts D, Tang KK, Symonds‐Tayler R, Tahavori F, Wells K, Donovan E. Low-cost Kinect Version 2 imaging system for breath hold monitoring and gating: Proof of concept study for breast cancer VMAT radiotherapy. J Appl Clin Med Phys 2018; 19:71-78. [PMID: 29536664 PMCID: PMC5978957 DOI: 10.1002/acm2.12286] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Revised: 11/12/2017] [Accepted: 01/09/2018] [Indexed: 11/30/2022] Open
Abstract
Voluntary inspiration breath hold (VIBH) for left breast cancer patients has been shown to be a safe and effective method of reducing radiation dose to the heart. Currently, VIBH protocol compliance is monitored visually. In this work, we establish whether it is possible to gate the delivery of radiation from an Elekta linac using the Microsoft Kinect version 2 (Kinect v2) depth sensor to measure a patient breathing signal. This would allow contactless monitoring during VMAT treatment, as an alternative to equipment-assisted methods such as active breathing control (ABC). Breathing traces were acquired from six left breast radiotherapy patients during VIBH. We developed a gating interface to an Elekta linac, using the depth signal from a Kinect v2 to control radiation delivery to a programmable motion platform following patient breathing patterns. Radiation dose to a moving phantom with gating was verified using point dose measurements and a Delta4 verification phantom. 60 breathing traces were obtained with an acquisition success rate of 100%. Point dose measurements for gated deliveries to a moving phantom agreed to within 0.5% of ungated delivery to a static phantom using both a conventional and VMAT treatment plan. Dose measurements with the verification phantom showed that there was a median dose difference of better than 0.5% and a mean (3% 3 mm) gamma index of 92.6% for gated deliveries when using static phantom data as a reference. It is possible to use a Kinect v2 device to monitor voluntary breath hold protocol compliance in a cohort of left breast radiotherapy patients. Furthermore, it is possible to use the signal from a Kinect v2 to gate an Elekta linac to deliver radiation only during the peak inhale VIBH phase.
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Affiliation(s)
- David M. Edmunds
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
| | | | - Komel Khabra
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
| | - Anna Kirby
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
| | - Poonam Madhale
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
| | - Helen McNair
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
| | - David Roberts
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
| | - KK Tang
- Department of PhysicsUniversity of SurreyGuildfordUK
| | | | - Fatemeh Tahavori
- Centre for Vision, Speech and Signal ProcessingUniversity of SurreyGuildfordUK
| | - Kevin Wells
- Centre for Vision, Speech and Signal ProcessingUniversity of SurreyGuildfordUK
| | - Ellen Donovan
- Department of PhysicsThe Royal Marsden NHS Foundation TrustLondonUK
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Töger J, Arvidsson PM, Bock J, Kanski M, Pedrizzetti G, Carlsson M, Arheden H, Heiberg E. Hemodynamic forces in the left and right ventricles of the human heart using 4D flow magnetic resonance imaging: Phantom validation, reproducibility, sensitivity to respiratory gating and free analysis software. PLoS One 2018; 13:e0195597. [PMID: 29621344 PMCID: PMC5886587 DOI: 10.1371/journal.pone.0195597] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Accepted: 03/26/2018] [Indexed: 01/17/2023] Open
Abstract
Purpose To investigate the accuracy, reproducibility and sensitivity to respiratory gating, field strength and ventricle segmentation of hemodynamic force quantification in the left and right ventricles of the heart (LV and RV) using 4D-flow magnetic resonance imaging (MRI), and to provide free hemodynamic force analysis software. Materials and methods A pulsatile flow phantom was imaged using 4D flow MRI and laser-based particle image velocimetry (PIV). Cardiac 4D flow MRI was performed in healthy volunteers at 1.5T (n = 23). Reproducibility was investigated using MR scanners from two different vendors on the same day (n = 8). Subsets of volunteers were also imaged without respiratory gating (n = 17), at 3T on the same day (n = 6), and 1–12 days later on the same scanner (n = 9, median 6 days). Agreement was measured using the intraclass correlation coefficient (ICC). Results Phantom validation showed good accuracy for both scanners (Scanner 1: bias -14±9%, y = 0.82x+0.08, R2 = 0.96, Scanner 2: bias -12±8%, y = 0.99x-0.08, R2 = 1.00). Force reproducibility was strong in the LV (0.09±0.07 vs 0.09±0.07 N, bias 0.00±0.04 N, ICC = 0.87) and RV (0.09±0.06 vs 0.09±0.05 N, bias 0.00±0.03, ICC = 0.83). Strong to very strong agreement was found for scans with and without respiratory gating (LV/RV: ICC = 0.94/0.95), scans on different days (ICC = 0.92/0.87), and 1.5T and 3T scans (ICC = 0.93/0.94). Conclusion Software for quantification of hemodynamic forces in 4D-flow MRI was developed, and results show high accuracy and strong to very strong reproducibility for both the LV and RV, supporting its use for research and clinical investigations. The software including source code is released freely for research.
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Affiliation(s)
- Johannes Töger
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
| | - Per M. Arvidsson
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
| | - Jelena Bock
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
| | - Mikael Kanski
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
| | - Gianni Pedrizzetti
- Department of Engineering and Architecture, University of Trieste, Trieste, Italy
| | - Marcus Carlsson
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
| | - Håkan Arheden
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
| | - Einar Heiberg
- Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden
- Department of Biomedical Engineering, Faculty of Engineering, Lund University, Lund, Sweden
- * E-mail:
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Zeng G, Teng Y, Zhu J, Zhu D, Yang B, Hu L, Chen M, Fu X. Clinical application of MRI-respiratory gating technology in the evaluation of children with obstructive sleep apnea hypopnea syndrome. Medicine (Baltimore) 2018; 97:e9680. [PMID: 29369187 PMCID: PMC5794371 DOI: 10.1097/md.0000000000009680] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
The objective of the present study was to investigate the clinical application of magnetic resonance imaging (MRI)-respiratory gating technology for assessing illness severity in children with obstructive sleep apnea hypopnea syndrome (OSAHS).MRI-respiratory gating technology was used to scan the nasopharyngeal cavities of 51 children diagnosed with OSAHS during 6 respiratory phases. Correlations between the ratio of the area of the adenoid to the area of the nasopalatine pharyngeal cavity (Sa/Snp), with the main indexes of polysomnography (PSG), were analyzed. Receiver operator characteristic (ROC) curve and Kappa analysis were used to determine the diagnostic accuracy of Sa/Snp in pediatric OSAHS.The Sa/Snp was positively correlated with the apnea hypopnea index (AHI) (P < .001) and negatively correlated with the lowest oxygen saturation of blood during sleep (LaSO2) (P < .001). ROC analysis in the 6 respiratory phases showed that the area under the curve (AUC) of the Sa/Snp in the end-expiratory phase was the largest (0.992, P < .001), providing a threshold of 69.5% for the diagnosis of severe versus slight-moderate OSAHS in children. Consistency analysis with the AHI showed a diagnosis accordance rate of 96.0% in severe pediatric OSAHS and 96.2% in slight-moderate pediatric OSAHS (Kappa = 0.922, P < .001).Stenosis of the nasopalatine pharyngeal cavity in children with adenoidal hypertrophy was greatest at the end-expiration phase during sleep. The end-expiratory Sa/Snp obtained by a combination of MRI and respiratory gating technology has potential as an important imaging index for diagnosing and evaluating severity in pediatric OSAHS.
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Affiliation(s)
- Guohui Zeng
- Department of Otorhinolaryngology Head and Neck Surgery
| | - Yaoshu Teng
- Department of Otorhinolaryngology Head and Neck Surgery
| | - Jin Zhu
- Department of Otorhinolaryngology Head and Neck Surgery
| | - Darong Zhu
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang Chinese Medical University, Hangzhou, China
| | - Bin Yang
- Department of Radiology, Hangzhou First People's Hospital, Zhejiang Chinese Medical University, Hangzhou, China
| | - Linpin Hu
- Department of Otorhinolaryngology Head and Neck Surgery
| | - Manman Chen
- Department of Otorhinolaryngology Head and Neck Surgery
| | - Xiao Fu
- Department of Otorhinolaryngology Head and Neck Surgery
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Lassen ML, Rasmussen T, Christensen TE, Kjær A, Hasbak P. Respiratory gating in cardiac PET: Effects of adenosine and dipyridamole. J Nucl Cardiol 2017; 24:1941-1949. [PMID: 27604107 DOI: 10.1007/s12350-016-0631-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 07/26/2016] [Indexed: 11/30/2022]
Abstract
BACKGROUND Respiratory motion due to breathing during cardiac positron emission tomography (PET) results in spatial blurring and erroneous tracer quantification. Respiratory gating might represent a solution by dividing the PET coincidence dataset into smaller respiratory phase subsets. The aim of our study was to compare the resulting imaging quality by the use of a time-based respiratory gating system in two groups administered either adenosine or dipyridamole as the pharmacological stress agent. METHODS AND RESULTS Forty-eight patients were randomized to adenosine or dipyridamole cardiac stress 82RB-PET. Respiratory rates and depths were measured by a respiratory gating system in addition to registering actual respiratory rates. Patients undergoing adenosine stress showed a decrease in measured respiratory rate from initial to later scan phase measurements [12.4 (±5.7) vs 5.6 (±4.7) min-1, P < .001] and tended to have a lower frequency of successful respiratory gating compared to dipyridamole (47% vs 71%, P = .12). As a result, imaging quality was superior in the dipyridamole group compared to adenosine. CONCLUSIONS If respiratory gating is considered for use in cardiac PET, a dipyridamole stress protocol is recommended as it, compared to adenosine, causes a more uniform respiration and results in a higher frequency of successful respiratory gating and thereby superior imaging quality.
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Affiliation(s)
- Martin Lyngby Lassen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Section 4011, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Thomas Rasmussen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Section 4011, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark.
| | - Thomas E Christensen
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Section 4011, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Andreas Kjær
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Section 4011, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
| | - Philip Hasbak
- Department of Clinical Physiology, Nuclear Medicine & PET and Cluster for Molecular Imaging, Section 4011, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, 2100, Copenhagen, Denmark
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Dyverfeldt P, Ebbers T. Comparison of respiratory motion suppression techniques for 4D flow MRI. Magn Reson Med 2017; 78:1877-1882. [PMID: 28074541 PMCID: PMC6084364 DOI: 10.1002/mrm.26574] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 11/11/2016] [Accepted: 11/17/2016] [Indexed: 11/22/2022]
Abstract
PURPOSE The purpose of this work was to assess the impact of respiratory motion and to compare methods for suppression of respiratory motion artifacts in 4D Flow MRI. METHODS A numerical 3D aorta phantom was designed based on an aorta velocity field obtained by computational fluid mechanics. Motion-distorted 4D Flow MRI measurements were simulated and several different motion-suppression techniques were evaluated: Gating with fixed acceptance window size, gating with different window sizes in inner and outer k-space, and k-space reordering. Additionally, different spatial resolutions were simulated. RESULTS Respiratory motion reduced the image quality. All motion-suppression techniques improved the data quality. Flow rate errors of up to 30% without gating could be reduced to less than 2.5% with the most successful motion suppression methods. Weighted gating and gating combined with k-space reordering were advantageous compared with conventional fixed-window gating. Spatial resolutions finer than the amount of accepted motion did not lead to improved results. CONCLUSION Respiratory motion affects 4D Flow MRI data. Several different motion suppression techniques exist that are capable of reducing the errors associated with respiratory motion. Spatial resolutions finer than the degree of accepted respiratory motion do not result in improved data quality. Magn Reson Med 78:1877-1882, 2017. © 2017 International Society for Magnetic Resonance in Medicine.
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Affiliation(s)
- Petter Dyverfeldt
- Division of Cardiovascular MedicineDepartment of Medical and Health Sciences, Linköping UniversityLinköpingSweden
- Center for Medical Image Science and Visualization (CMIV), Linköping UniversityLinköpingSweden
| | - Tino Ebbers
- Division of Cardiovascular MedicineDepartment of Medical and Health Sciences, Linköping UniversityLinköpingSweden
- Center for Medical Image Science and Visualization (CMIV), Linköping UniversityLinköpingSweden
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Hyun MC, Gerlach J, Rubeaux M, Slomka PJ. Technical consideration for dual ECG/respiratory-gated cardiac PET imaging. J Nucl Cardiol 2017; 24:1246-1252. [PMID: 27943053 DOI: 10.1007/s12350-016-0741-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 11/11/2016] [Indexed: 12/01/2022]
Affiliation(s)
- Mark C Hyun
- Division of Nuclear Medicine, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Cardiac Imaging Research, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
- Artificial Intelligence in Medicine Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | - Jim Gerlach
- Division of Nuclear Medicine, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Cardiac Imaging Research, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Artificial Intelligence in Medicine Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Mathieu Rubeaux
- Division of Nuclear Medicine, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Cardiac Imaging Research, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Artificial Intelligence in Medicine Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Piotr J Slomka
- Division of Nuclear Medicine, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Cardiac Imaging Research, Department of Imaging, Cedars-Sinai Medical Center, Los Angeles, CA, USA
- Artificial Intelligence in Medicine Program, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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Kaza E, Dunlop A, Panek R, Collins DJ, Orton M, Symonds‐Tayler R, McQuaid D, Scurr E, Hansen V, Leach MO. Lung volume reproducibility under ABC control and self-sustained breath-holding. J Appl Clin Med Phys 2017; 18:154-162. [PMID: 28300372 PMCID: PMC5689958 DOI: 10.1002/acm2.12034] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 10/09/2016] [Indexed: 12/25/2022] Open
Abstract
An Active Breathing Coordinator (ABC) can be employed to induce breath-holds during CT imaging and radiotherapy of lung, breast and liver cancer, and recently during lung cancer MRI. The apparatus measures and controls respiratory volume, hence subject lung volume reproducibility is its principal measure of effectiveness. To assess ABC control quality, the intra-session reproducibility of ABC-induced lung volumes was evaluated and compared with that reached by applying the clinical standard of operator-guided self-sustained breath-holds on healthy volunteers during MRI. Inter-session reproducibility was investigated by repeating ABC-controlled breath-holds on a second visit. Additionally, lung volume agreement with ABC devices used with different imaging modalities in the same institution (MR, CT), or for a breast trial treatment, was assessed. Lung volumes were derived from three-dimensional (3D) T1-weighted MRI datasets by three observers employing semiautomatic lung delineation on a radiotherapy treatment planning system. Inter-observer variability was less than 6% of the delineated lung volumes. Lung volume agreement between the different conditions over all subjects was investigated using descriptive statistics. The ABC equipment dedicated for MR application exhibited good intra-session and inter-session lung volume reproducibility (1.8% and 3% lung volume variability on average, respectively). MR-assessed lung volumes were similar using different ABC equipment dedicated to MR, CT, or breast radiotherapy. Overall, lung volumes controlled by the same or different ABC devices agreed better than with self-controlled breath-holds, as suggested by the average ABC variation of 1.8% of the measured lung volumes (99 mL), compared to the 4.1% (226 mL) variability observed on average with self-sustained breath-holding.
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Affiliation(s)
- Evangelia Kaza
- CR‐UK Cancer Imaging CentreInstitute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Alex Dunlop
- Joint Department of PhysicsThe Institute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Rafal Panek
- CR‐UK Cancer Imaging CentreInstitute of Cancer Research and Royal Marsden HospitalLondonUK
| | - David J. Collins
- CR‐UK Cancer Imaging CentreInstitute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Matthew Orton
- CR‐UK Cancer Imaging CentreInstitute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Richard Symonds‐Tayler
- Joint Department of PhysicsThe Institute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Dualta McQuaid
- Joint Department of PhysicsThe Institute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Erica Scurr
- The Royal Marsden NHS Foundation TrustLondonUK
| | - Vibeke Hansen
- Joint Department of PhysicsThe Institute of Cancer Research and Royal Marsden HospitalLondonUK
| | - Martin O. Leach
- CR‐UK Cancer Imaging CentreInstitute of Cancer Research and Royal Marsden HospitalLondonUK
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Jermoumi M, Xie R, Cao D, Housley DJ, Shepard DM. Does gated beam delivery impact delivery accuracy on an Elekta linac? J Appl Clin Med Phys 2017; 18:90-95. [PMID: 28291908 PMCID: PMC5689903 DOI: 10.1002/acm2.12020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 10/04/2016] [Indexed: 11/17/2022] Open
Abstract
In this study, we evaluated the performance of an Elekta linac in the delivery of gated radiotherapy. Delivery accuracy was examined with an emphasis on the impact of using short gating windows (low monitor unit beam-on segments) or long beam hold times. The performance was assessed using a 20cm by 20cm open field with the radiation delivered using a range of beam-on and beam-off time periods. Gated delivery measurements were also performed for two SBRT plans delivered using volumetric modulated arc therapy (VMAT). Tests included both free-breathing based gating (covering a variety of gating windows) and simulated breath-hold based gating. An IBA MatriXX 2D ion chamber array was used for data collection, and the gating accuracy at low MU was evaluated using gamma passing rates. For the 20 cm by 20 cm open field, the measurements generally showed close agreement between the gated and non-gated beam deliveries. Discrepancies, however, began to appear with a 5-to-1 ratio of the beam-off to beam-on times. The discrepancies observed for these tight gating windows can be attributed to the small number of monitor units delivered during each beam-on segment. Dose distribution analysis from the delivery of the two SBRT plans showed gamma passing rates (± 1%, 2%/1 mm) in the range of 95% to 100% for gating windows of 25%, 38%, 50%, 63%, 75%, and 83%. Using a simulated sinusoidal breathing signal with a 4 second period, the gamma passing rate of free-breathing gating and breath-hold gating deliveries were measured in the range of 95.7% to 100%. In conclusion, the results demonstrate that Elekta linacs can accurately deliver respiratory gated treatments for both free-breathing and breath-hold patients. Some caution should be exercised with the use of very tight gating windows.
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Affiliation(s)
- Mohammed Jermoumi
- Department of Radiation OncologySwedish Cancer InstituteSeattleWAUSA
| | - Roger Xie
- Department of Radiation OncologyIronwood Cancer and Research CenterScottsdaleAZUSA
| | - Daliang Cao
- Department of Radiation OncologySwedish Cancer InstituteSeattleWAUSA
| | - David J. Housley
- Department of Radiation OncologySwedish Cancer InstituteSeattleWAUSA
| | - David M. Shepard
- Department of Radiation OncologySwedish Cancer InstituteSeattleWAUSA
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Hill MA, Vojnovic B. Implications of respiratory motion for small animal image-guided radiotherapy. Br J Radiol 2017; 90:20160482. [PMID: 27384471 PMCID: PMC5605024 DOI: 10.1259/bjr.20160482] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 06/24/2016] [Accepted: 06/28/2016] [Indexed: 11/06/2022] Open
Abstract
Image-guided small animal irradiators have the potential to make a significant impact on facilitating the translation of radiobiological research into the clinic. To fully exploit the improved precision in dose delivery to the target/tumour while minimizing dose to surrounding tissues, minimal positional error in the target is required. However, for many sites within the thorax and abdomen, respiratory motion may be a critical factor in limiting the accuracy of beam delivery and until now, very little attention has been paid to the impact and management of this motion. We report on the implications of respiratory motion with respect to the negative impact of delivered dose distributions and their assessment, ways being developed to effectively manage this motion, so that beam delivery only occurs during the stationary resting phase of the breathing cycle, and comment on the need to effectively integrate these developments into the software used to plan and control beam delivery. Altogether, the implementation of respiratory-gated imaging and beam delivery will lead to significant improvements in the precision in dose delivery and constitutes an important development for preclinical radiotherapy studies.
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Affiliation(s)
- Mark A Hill
- Cancer Research UK/Medical Research Council Oxford Institute for Radiation Oncology, Gray Laboratories, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Borivoj Vojnovic
- Cancer Research UK/Medical Research Council Oxford Institute for Radiation Oncology, Gray Laboratories, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
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Zhou Z, Han F, Rapacchi S, Nguyen KL, Brunengraber DZ, Kim GHJ, Finn JP, Hu P. Accelerated ferumoxytol-enhanced 4D multiphase, steady-state imaging with contrast enhancement (MUSIC) cardiovascular MRI: validation in pediatric congenital heart disease. NMR Biomed 2017; 30:10.1002/nbm.3663. [PMID: 27862507 PMCID: PMC5298926 DOI: 10.1002/nbm.3663] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 10/04/2016] [Accepted: 10/05/2016] [Indexed: 05/09/2023]
Abstract
The purpose of this work was to validate a parallel imaging (PI) and compressed sensing (CS) combined reconstruction method for a recently proposed 4D non-breath-held, multiphase, steady-state imaging technique (MUSIC) cardiovascular MRI in a cohort of pediatric congenital heart disease patients. We implemented a graphics processing unit accelerated CS-PI combined reconstruction method and applied it in 13 pediatric patients who underwent cardiovascular MRI after ferumoxytol administration. Conventional breath-held contrast-enhanced magnetic resonance angiography (CE-MRA) was first performed during the first pass of ferumoxytol injection, followed by the original MUSIC and the proposed CS-PI MUSIC during the steady-state distribution phase of ferumoxytol. Qualities of acquired images were then evaluated using a four-point scale. Left ventricular volumes and ejection fractions calculated from the original MUSIC and the CS-PI MUSIC were also compared with conventional multi-slice 2D cardiac cine MRI. The proposed CS-PI MUSIC reduced the imaging time of the MUSIC acquisition to 4.6 ± 0.4 min from 8.9 ± 1.2 min. Computationally intensive image reconstruction was completed within 5 min without interruption of sequential clinical scans. The proposed method (mean 3.3-4.0) provided image quality comparable to that of the original MUSIC (3.2-4.0) (all P ≥ 0.42), and better than conventional breath-held first-pass CE-MRA (1.1-3.3) for 13 anatomical structures (all P ≤ 0.0014) with good inter-observer agreement (κ > 0.46). The calculated ventricular volumes and ejection fractions from both original MUSIC (r > 0.90) and CS-PI MUSIC (r > 0.85) correlated well with 2D cine imaging. In conclusion, PI and CS were successfully incorporated into the 4D MUSIC acquisition to further reduce scan time by approximately 50% while maintaining highly comparable image quality in a clinically practical reconstruction time.
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Affiliation(s)
- Ziwu Zhou
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Fei Han
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Stanislas Rapacchi
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Kim-Lien Nguyen
- Department of Medicine, Division of Cardiology, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Division of Cardiology, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Daniel Z Brunengraber
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Grace-Hyun J. Kim
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - J. Paul Finn
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Biomedical Physics Inter-Departmental Graduate Program, University of California, Los Angeles, CA, USA
| | - Peng Hu
- Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
- Department of Bioengineering, University of California, Los Angeles, CA, USA
- Biomedical Physics Inter-Departmental Graduate Program, University of California, Los Angeles, CA, USA
- Correspondence to: Peng Hu, PhD, Department of Radiological Sciences, 300 UCLA Medical Plaza Suite B119, Los Angeles, CA 90095.
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Ter Voert EEGW, Heijmen L, Punt CJA, de Wilt JHW, van Laarhoven HWM, Heerschap A. Reduced respiratory motion artifacts using structural similarity in fast 2D dynamic contrast enhanced MRI of liver lesions. NMR Biomed 2016; 29:1526-1535. [PMID: 27598946 DOI: 10.1002/nbm.3606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 07/21/2016] [Accepted: 07/25/2016] [Indexed: 06/06/2023]
Abstract
The purpose of this work was to improve dynamic contrast enhanced MRI (DCE-MRI) of liver lesions by removing motion corrupted images as identified by a structural similarity (SSIM) algorithm, and to assess the effect of this correction on the pharmacokinetic parameter Ktrans using automatically determined arterial input functions (AIFs). Fifteen patients with colorectal liver metastases were measured twice with a T1 weighted multislice 2D FLASH sequence for DCE-MRI (time resolution 1.2 s). AIFs were automatically derived from contrast inflow in the aorta of each patient. Thereafter, SSIM identified motion corrupted images of the liver were removed from the DCE dataset. From this corrected data set Ktrans and its reproducibility were determined. Using the SSIM algorithm a median fraction of 46% (range 37-50%) of the liver images in DCE time series was labeled as motion distorted. Rejection of these images resulted in a significantly lower median Ktrans (p < 0.05) and lower coefficient of repeatability of Ktrans in liver metastases compared with an analysis without correction. SSIM correction improves the reproducibility of the DCE-MRI parameter Ktrans in liver metastasis and reduces contamination of Ktrans values of lesions by that of surrounding normal liver tissue.
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Affiliation(s)
- Edwin E G W Ter Voert
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Linda Heijmen
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Medical Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Cornelis J A Punt
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Johannes H W de Wilt
- Department of Surgery, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hanneke W M van Laarhoven
- Department of Medical Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Arend Heerschap
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
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Huo M, Gorayski P, Pinkham MB, Lehman M. Advances in radiotherapy technology for non-small cell lung cancer: What every general practitioner should know. Aust Fam Physician 2016; 45:805-809. [PMID: 27806449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
BACKGROUND Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related death in Australia. Radiotherapy plays an important role in the curative and palliative settings. OBJECTIVE This article reviews recent technological advances that have expanded the radiotherapy treatment options available, and presents standard and emerging approaches to NSCLC. DISCUSSION General practitioners play an integral role in the care and education of patients during diagnosis, treatment and
follow-up of NSCLC. Stereotactic (ablative) body radiotherapy,
intensity-modulated radiotherapy, intracranial radiosurgery and hippocampal-avoidance whole-brain radiotherapy are discussed in this article.
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Yoon MS, Jeong JU, Nam TK, Ahn SJ, Chung WK, Song JY. Evaluation of Dose Distribution in Intensity Modulated Radiosurgery for Lung Cancer under Condition of Respiratory Motion. PLoS One 2016; 11:e0163112. [PMID: 27648949 PMCID: PMC5029809 DOI: 10.1371/journal.pone.0163112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/04/2016] [Indexed: 11/26/2022] Open
Abstract
The dose of a real tumor target volume and surrounding organs at risk (OARs) under the effect of respiratory motion was calculated for a lung tumor plan, based on the target volume covering the whole tumor motion range for intensity modulated radiosurgery (IMRS). Two types of IMRS plans based on simulated respiratory motion were designed using humanoid and dynamic phantoms. Delivery quality assurance (DQA) was performed using ArcCHECK and MapCHECK2 for several moving conditions of the tumor and the real dose inside the humanoid phantom was evaluated using the 3DVH program. This evaluated dose in the tumor target and OAR using the 3DVH program was higher than the calculated dose in the plan, and a greater difference was seen for the RapidArc treatment than for the standard intensity modulated radiation therapy (IMRT) with fixed gantry angle beams. The results of this study show that for IMRS plans based on target volume, including the whole tumor motion range, tighter constraints of the OAR should be considered in the optimization process. The method devised in this study can be applied effectively to analyze the dose distribution in the real volume of tumor target and OARs in IMRT plans targeting the whole tumor motion range.
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Affiliation(s)
- Mee Sun Yoon
- Department of Radiation Oncology, Chonnam National University Medical School, Gwangju, Korea
| | - Jae-Uk Jeong
- Department of Radiation Oncology, Chonnam National University Medical School, Gwangju, Korea
| | - Taek-Keun Nam
- Department of Radiation Oncology, Chonnam National University Medical School, Gwangju, Korea
| | - Sung-Ja Ahn
- Department of Radiation Oncology, Chonnam National University Medical School, Gwangju, Korea
| | - Woong-Ki Chung
- Department of Radiation Oncology, Chonnam National University Medical School, Gwangju, Korea
| | - Ju-Young Song
- Department of Radiation Oncology, Chonnam National University Medical School, Gwangju, Korea
- * E-mail:
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Kokki T, Klén R, Noponen T, Pärkkä J, Saunavaara V, Hoppela E, Teräs M, Knuuti J. Linear relation between spirometric volume and the motion of cardiac structures: MRI and clinical PET study. J Nucl Cardiol 2016; 23:475-85. [PMID: 25698470 DOI: 10.1007/s12350-014-0057-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 12/11/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND In cardiac PET, CT, and MRI respiration is major reason for impaired image quality of small targets such as coronary arteries. Strong correlations between heart motion and respiratory signals have been detected but quantitative relation between signals and motion of cardiac structures in MRI or PET is not reported . METHODS Relation between spirometric lung volume or pressure belt signal and motion of coronary vessels in MRI was studied on nine healthy volunteers. Spirometry was further applied to (18)F-FDG cardiac PET study to determine quantitative relation between volume change and motion of center of myocardium activity (CMA) on nine CAD patients. RESULTS Correlation coefficients (CC) between vessel motions and volume or pressure changes were 0.90-0.92 or 0.86-0.84, respectively. The linear equations based on volume or pressure changes derived 2.0-2.6 or 2.9-3.3 mm mean estimation error for vessel motions. In PET CC value of 0.93 was determined between volume changes and CMA motions. The linear equation based on volume change derived maximum estimation error of 2.5 mm for CMA motion. CONCLUSION The spirometric volume change linearly estimates motion of myocardium in PET with good accuracy and have potential to guide selection of optimal number of respiratory gates in cardiac PET.
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Affiliation(s)
- Tommi Kokki
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland.
- Department of Clinical Physiology and Radioisotope Imaging, Turku University Hospital, 20521, Turku, Finland.
| | - Riku Klén
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
- Department of Mathematics and Statistics, University of Turku, 20014, Turku, Finland
| | - Tommi Noponen
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
| | - Jussi Pärkkä
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
- Department of Clinical Physiology and Radioisotope Imaging, Turku University Hospital, 20521, Turku, Finland
| | - Virva Saunavaara
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
| | - Erika Hoppela
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
| | - Mika Teräs
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
| | - Juhani Knuuti
- Turku PET Centre, University of Turku and Turku University Hospital, PO BOX 52, 20521, Turku, Finland
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Todica A, Lehner S, Wang H, Zacherl MJ, Nekolla K, Mille E, Xiong G, Bartenstein P, la Fougère C, Hacker M, Böning G. Derivation of a respiration trigger signal in small animal list-mode PET based on respiration-induced variations of the ECG signal. J Nucl Cardiol 2016; 23:73-83. [PMID: 26068972 DOI: 10.1007/s12350-015-0154-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 04/15/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Raw PET list-mode data contains motion artifacts causing image blurring and decreased spatial resolution. Unless corrected, this leads to underestimation of the tracer uptake and overestimation of the lesion size, as well as inaccuracies with regard to left ventricular volume and ejection fraction (LVEF), especially in small animal imaging. METHODS AND RESULTS A respiratory trigger signal from respiration-induced variations in the electro-cardiogram (ECG) was detected. Original and revised list-mode PET data were used for calculation of left ventricular function parameters using both respiratory gating techniques. For adequately triggered datasets we saw no difference in mean respiratory cycle period between the reference standard (RRS) and the ECG-based (ERS) methods (1120 ± 159 ms vs 1120 ± 159 ms; P = n.s.). While the ECG-based method showed somewhat higher signal noise (66 ± 22 ms vs 51 ± 29 ms; P < .001), both respiratory triggering techniques yielded similar estimates for EDV, ESV, LVEF (RRS: 387 ± 56 µL, 162 ± 34 µL, 59 ± 5%; ERS: 389 ± 59 µL, 163 ± 35 µL, 59 ± 4%; P = n.s.). CONCLUSIONS This study showed that respiratory gating signals can be accurately derived from cardiac trigger information alone, without the additional requirement for dedicated measurement of the respiratory motion in rats.
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Affiliation(s)
- Andrei Todica
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany.
| | - Sebastian Lehner
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - Hao Wang
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - Mathias J Zacherl
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - Katharina Nekolla
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - Erik Mille
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - Guoming Xiong
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
- German Center for Vertigo and Balance Disorders, DSGZ, University of Munich, Munich, Germany
| | - Peter Bartenstein
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
| | - Christian la Fougère
- Department of Clinical Molecular Imaging and Nuclear Medicine, University Hospital Tübingen, Tübingen, Germany
| | - Marcus Hacker
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University Vienna, Vienna, Austria
| | - Guido Böning
- Department of Nuclear Medicine, University of Munich, Marchioninistr. 15, 81377, Munich, Germany
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van Ooij P, Semaan E, Schnell S, Giri S, Stankovic Z, Carr J, Barker AJ, Markl M. Improved respiratory navigator gating for thoracic 4D flow MRI. Magn Reson Imaging 2015; 33:992-9. [PMID: 25940391 DOI: 10.1016/j.mri.2015.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2014] [Revised: 04/25/2015] [Accepted: 04/27/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND Thoracic and abdominal 4D flow MRI is typically acquired in combination with navigator respiration control which can result in highly variable scan efficiency (Seff) and thus total scan time due to inter-individual variability in breathing patterns. The aim of this study was to test the feasibility of an improved respiratory control strategy based on diaphragm navigator gating with fixed Seff, respiratory driven phase encoding, and a navigator training phase. METHODS 4D flow MRI of the thoracic aorta was performed in 10 healthy subjects at 1.5T and 3T systems for the in-vivo assessment of aortic time-resolved 3D blood flow velocities. For each subject, four 4D flow scans (1: conventional navigator gating, 2-4: new implementation with fixed Seff =60%, 80% and 100%) were acquired. Data analysis included semi-quantitative evaluation of image quality of the 4D flow magnitude images (image quality grading on a four point scale), 3D segmentation of the thoracic aorta, and voxel-by-voxel comparisons of systolic 3D flow velocity vector fields between scans. RESULTS Conventional navigator gating resulted in variable Seff=74±13% (range=56%-100%) due to inter-individual variability of respiration patterns. For scans 2-4, the new navigator implementation was able to achieve predictable total scan times with stable Seff, only depending on heart rate. Semi- and fully quantitative analysis of image quality in 4D flow magnitude images was similar for the new navigator scheme compared to conventional navigator gating. For aortic systolic 3D velocities, good agreement was found between all new navigator settings (scan 2-4) with the conventional navigator gating (scan 1) with best performance for Seff=80% (mean difference=-0.01 m/s; limits of agreement=0.23 m/s, Pearson's ρ=0.89, p<0.001). No significant differences for image quality or 3D systolic velocities were found for 1.5T compared to 3T. CONCLUSIONS The findings of this study demonstrate the feasibility of the new navigator scheme to acquire 4D flow data with more predictable scan time while maintaining image quality and 3D velocity information, which may prove beneficial for clinical applications.
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Affiliation(s)
- Pim van Ooij
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Edouard Semaan
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Susanne Schnell
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Zoran Stankovic
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - James Carr
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Alex J Barker
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Michael Markl
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Biomedical Engineering, McCormick School of Engineering, Northwestern University, Chicago, IL, USA.
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Ko CL, Wu YW, Cheng MF, Yen RF, Wu WC, Tzen KY. Data-driven respiratory motion tracking and compensation in CZT cameras: a comprehensive analysis of phantom and human images. J Nucl Cardiol 2015; 22:308-18. [PMID: 25120132 DOI: 10.1007/s12350-014-9963-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 07/10/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND This study described a method for tracking and compensating respiratory motion in cadmium-zinc-telluride (CZT) cameras. We evaluated motion effects on myocardial perfusion imaging and assessed the usefulness of motion compensation in phantom and clinical studies. METHODS SPECT studies were obtained from an oscillating heart phantom and 552 patients using CZT cameras with list-mode acquisition. Images were reformatted in 500-ms frames, and the activity centroid was calculated as respiratory signal. The myocardial perfusion, left ventricular (LV) wall thickness, and LV volume were assessed before and after the motion compensation technique. RESULTS In phantom studies, we documented only minimal bias between simulated and measured shifts. Significantly reduced tracer activity, increased wall thickness and decreased volume in scans with 15 mm or more axial shifts were noted. In clinical studies, there was a higher prevalence of significant motion after treadmill exercise. The motion compensation technique could successfully compensate those motion artifacts. CONCLUSION The described method allows for tracking and compensating respiratory motion in CZT cameras. Significant respiratory motion is still not uncommon using CZT cameras, especially in patients who underwent treadmill tests. Motion blurring can be compensated using image processing techniques and image quality could be significantly improved.
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Affiliation(s)
- Chi-Lun Ko
- Department of Nuclear Medicine, National Taiwan University Hospital Yun-Lin Branch, No. 579, Sec. 2, Yunlin Rd., Douliou City, 640, Yunlin County, Taiwan,
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Freislederer P, Reiner M, Hoischen W, Quanz A, Heinz C, Walter F, Belka C, Soehn M. Characteristics of gated treatment using an optical surface imaging and gating system on an Elekta linac. Radiat Oncol 2015; 10:68. [PMID: 25881018 PMCID: PMC4387684 DOI: 10.1186/s13014-015-0376-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 03/08/2015] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Knowing the technical characteristics of gated radiotherapy equipment is crucial for ensuring precise and accurate treatment when using techniques such as Deep-Inspiration Breath-Hold and gating under free breathing. With one of the first installations of the novel surface imaging system Catalyst™ (C-RAD AB, Sweden) in connection with an Elekta Synergy linear accelerator (Elekta AB, Sweden) via the Elekta Response Interface, characteristics like dose delivery accuracy and time delay were investigated prior to clinical implementation of gated treatments in our institution. METHODS In this study a moving phantom was used to simulate respiratory motion which was registered by the Catalyst™ system. The gating level was set manually. Within this gating window a trigger signal is automatically sent to the linac initiating treatment delivery. Dose measurements of gated linac treatment beams with different gating levels were recorded with a static 2D-Diode Array (MapCheck2, Sun Nuclear Co., USA) and compared to ungated reference measurements for different field sizes. In addition, the time delay of gated treatment beams was measured using radiographic film. RESULTS The difference in dose delivery between gated and ungated treatment decreases with the size of the chosen gating level. For clinically relevant gating levels of about 30%, the differences in dose delivery accuracy remain below 1%. In comparison with other system configurations in literature, the beam-on time delay shows a large deviation of 851 ms ± 100 ms. CONCLUSIONS When performing gated treatment, especially for free-breathing gating, factors as time delay and dose delivery have to be evaluated regularly in terms of a quality assurance process. Once these parameters are known they can be accounted and compensated for, e.g. by adjusting the pre-selected gating level or the internal target volume margins and by using prediction algorithms for breathing curves. The usage of prediction algorithms becomes inevitable with the high beam-on time delay which is reported here.
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Affiliation(s)
- Philipp Freislederer
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Michael Reiner
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Winfried Hoischen
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Anton Quanz
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Christian Heinz
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Franziska Walter
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Claus Belka
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
| | - Matthias Soehn
- Department of Radiation Oncology, LMU University Hospital, D-81377, Munich, Germany.
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Castillo SJ, Castillo R, Castillo E, Pan T, Ibbott G, Balter P, Hobbs B, Guerrero T. Evaluation of 4D CT acquisition methods designed to reduce artifacts. J Appl Clin Med Phys 2015; 16:4949. [PMID: 26103169 PMCID: PMC4504190 DOI: 10.1120/jacmp.v16i2.4949] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 11/21/2014] [Accepted: 11/09/2014] [Indexed: 12/25/2022] Open
Abstract
Four-dimensional computed tomography (4D CT) is used to account for respiratory motion in radiation treatment planning, but artifacts resulting from the acquisition and postprocessing limit its accuracy. We investigated the efficacy of three experimental 4D CT acquisition methods to reduce artifacts in a prospective institutional review board approved study. Eighteen thoracic patients scheduled to undergo radiation therapy received standard clinical 4D CT scans followed by each of the alternative 4D CT acquisitions: 1) data oversampling, 2) beam gating with breathing irregularities, and 3) rescanning the clinical acquisition acquired during irregular breathing. Relative values of a validated correlation-based artifact metric (CM) determined the best acquisition method per patient. Each 4D CT was processed by an extended phase sorting approach that optimizes the quantitative artifact metric (CM sorting). The clinical acquisitions were also postprocessed by phase sorting for artifact comparison of our current clinical implementation with the experimental methods. The oversampling acquisition achieved the lowest artifact presence among all acquisitions, achieving a 27% reduction from the current clinical 4D CT implementation (95% confidence interval = 34-20). The rescan method presented a significantly higher artifact presence from the clinical acquisition (37%; p < 0.002), the gating acquisition (26%; p < 0.005), and the oversampling acquisition (31%; p < 0.001), while the data lacked evidence of a significant difference between the clinical, gating, and oversampling methods. The oversampling acquisition reduced artifact presence from the current clinical 4D CT implementation to the largest degree and provided the simplest and most reproducible implementation. The rescan acquisition increased artifact presence significantly, compared to all acquisitions, and suffered from combination of data from independent scans over which large internal anatomic shifts occurred.
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Kaza E, Symonds-Tayler R, Collins DJ, McDonald F, McNair HA, Scurr E, Koh DM, Leach MO. First MRI application of an active breathing coordinator. Phys Med Biol 2015; 60:1681-96. [PMID: 25633183 PMCID: PMC5390947 DOI: 10.1088/0031-9155/60/4/1681] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 12/16/2014] [Accepted: 12/18/2014] [Indexed: 11/12/2022]
Abstract
A commercial active breathing coordinator (ABC) device, employed to hold respiration at a specific level for a predefined duration, was successfully adapted for magnetic resonance imaging (MRI) use for the first time. Potential effects of the necessary modifications were assessed and taken into account. Automatic MR acquisition during ABC breath holding was achieved. The feasibility of MR-ABC thoracic and abdominal examinations together with the advantages of imaging in repeated ABC-controlled breath holds were demonstrated on healthy volunteers. Five lung cancer patients were imaged under MR-ABC, visually confirming the very good intra-session reproducibility of organ position in images acquired with the same patient positioning as used for computed tomography (CT). Using identical ABC settings, good MR-CT inter-modality registration was achieved. This demonstrates the value of ABC, since application of T1, T2 and diffusion weighted MR sequences provides a wider range of contrast mechanisms and additional diagnostic information compared to CT, thus improving radiotherapy treatment planning and assessment.
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Affiliation(s)
- E Kaza
- CR-UK Cancer Imaging Centre, Institute of Cancer Research London and Royal Marsden Hospital, London, UK
| | - R Symonds-Tayler
- CR-UK Cancer Imaging Centre, Institute of Cancer Research London and Royal Marsden Hospital, London, UK
| | - D J Collins
- CR-UK Cancer Imaging Centre, Institute of Cancer Research London and Royal Marsden Hospital, London, UK
| | - F McDonald
- The Royal Marsden NHS Foundation Trust, UK
| | - H A McNair
- Department of Radiotherapy, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Sutton, UK
| | - E Scurr
- The Royal Marsden NHS Foundation Trust, UK
| | - D-M Koh
- The Royal Marsden NHS Foundation Trust, UK
| | - M O Leach
- CR-UK Cancer Imaging Centre, Institute of Cancer Research London and Royal Marsden Hospital, London, UK
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Jönsson M, Ceberg S, Nordström F, Thornberg C, Bäck SÅJ. Technical evaluation of a laser-based optical surface scanning system for prospective and retrospective breathing adapted computed tomography. Acta Oncol 2015; 54:261-5. [PMID: 25383452 DOI: 10.3109/0284186x.2014.948059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND For breathing adapted radiotherapy, the same motion monitoring system can be used for imaging and triggering of the accelerator. PURPOSE To evaluate a new technique for prospective gated computed tomography (CT) and four-dimensional CT (4DCT) using a laser based surface scanning system (Sentinel(™), C-RAD, Uppsala, Sweden). The system was compared to the AZ-733V respiratory gating system (Anzai Medical, Tokyo, Japan) and the Real-Time Position Management System (RPM(™)) (Varian Medical Systems, Palo Alto, CA, USA). MATERIAL AND METHODS Temporal accuracy was evaluated using a moving phantom programmed to move a platform along trajectories following a sin(6)(ωt) function with amplitudes from 6 to 20 mm and periods from 2 to 5 s during 120 s while the motion was recorded. The recorded data was Fourier transformed and the peak area at the fundamental and harmonic frequencies compared to data generated using the same sinusoidal function. For verification of the 4DCT reconstruction process, the phantom was programmed to move along a sinusoidal trajectory. Ten phase series were reconstructed. The distance from the couch to the platform was measured in each image. By fitting the function sin(ωt-ϕ) to the values measured in the images corresponding to each slice, the phase of each image was verified. RESULTS AND CONCLUSION In the recorded data, the peak area at the fundamental frequency covered on average 104 ± 4%, 102 ± 4% and 91 ± 27% of the peak area in the generated data for the Sentinel(™), RPM(™) and AZ-733V systems, respectively. All systems managed to resolve both harmonic frequencies. The second experiment showed that all images were sorted into the correct series using breathing data recorded by each system. The systems generated very similar results, however, it is preferable to use the same system both for imaging and treatment.
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Affiliation(s)
- Mattias Jönsson
- Department of Medical Radiation Physics, Department of Clinical Sciences Malmö, Lund University , Malmö , Sweden
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Miyamoto N, Ishikawa M, Sutherland K, Suzuki R, Matsuura T, Toramatsu C, Takao S, Nihongi H, Shimizu S, Umegaki K, Shirato H. A motion-compensated image filter for low-dose fluoroscopy in a real-time tumor-tracking radiotherapy system. J Radiat Res 2015; 56:186-196. [PMID: 25129556 PMCID: PMC4572582 DOI: 10.1093/jrr/rru069] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 07/14/2014] [Accepted: 07/14/2014] [Indexed: 06/03/2023]
Abstract
In the real-time tumor-tracking radiotherapy system, a surrogate fiducial marker inserted in or near the tumor is detected by fluoroscopy to realize respiratory-gated radiotherapy. The imaging dose caused by fluoroscopy should be minimized. In this work, an image processing technique is proposed for tracing a moving marker in low-dose imaging. The proposed tracking technique is a combination of a motion-compensated recursive filter and template pattern matching. The proposed image filter can reduce motion artifacts resulting from the recursive process based on the determination of the region of interest for the next frame according to the current marker position in the fluoroscopic images. The effectiveness of the proposed technique and the expected clinical benefit were examined by phantom experimental studies with actual tumor trajectories generated from clinical patient data. It was demonstrated that the marker motion could be traced in low-dose imaging by applying the proposed algorithm with acceptable registration error and high pattern recognition score in all trajectories, although some trajectories were not able to be tracked with the conventional spatial filters or without image filters. The positional accuracy is expected to be kept within ±2 mm. The total computation time required to determine the marker position is a few milliseconds. The proposed image processing technique is applicable for imaging dose reduction.
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Affiliation(s)
- Naoki Miyamoto
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Masayori Ishikawa
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Kenneth Sutherland
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Ryusuke Suzuki
- Department of Medical Physics, Hokkaido University Hospital, North-14 West-5, Kita-ku, Sapporo 060-8648, Japan
| | - Taeko Matsuura
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Chie Toramatsu
- Department of Medical Physics, Hokkaido University Hospital, North-14 West-5, Kita-ku, Sapporo 060-8648, Japan
| | - Seishin Takao
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Hideaki Nihongi
- Department of Medical Physics, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Shinichi Shimizu
- Department of Radiology, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Kikuo Umegaki
- Division of Quantum Science and Engineering, Graduate School of Engineering, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
| | - Hiroki Shirato
- Department of Radiology, Graduate School of Medicine, Hokkaido University, North-15 West-7, Kita-ku, Sapporo 060-8638, Japan
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Yip S, McCall K, Aristophanous M, Chen AB, Aerts HJWL, Berbeco R. Comparison of texture features derived from static and respiratory-gated PET images in non-small cell lung cancer. PLoS One 2014; 9:e115510. [PMID: 25517987 PMCID: PMC4269460 DOI: 10.1371/journal.pone.0115510] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 11/24/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND PET-based texture features have been used to quantify tumor heterogeneity due to their predictive power in treatment outcome. We investigated the sensitivity of texture features to tumor motion by comparing static (3D) and respiratory-gated (4D) PET imaging. METHODS Twenty-six patients (34 lesions) received 3D and 4D [18F]FDG-PET scans before the chemo-radiotherapy. The acquired 4D data were retrospectively binned into five breathing phases to create the 4D image sequence. Texture features, including Maximal correlation coefficient (MCC), Long run low gray (LRLG), Coarseness, Contrast, and Busyness, were computed within the physician-defined tumor volume. The relative difference (δ3D-4D) in each texture between the 3D- and 4D-PET imaging was calculated. Coefficient of variation (CV) was used to determine the variability in the textures between all 4D-PET phases. Correlations between tumor volume, motion amplitude, and δ3D-4D were also assessed. RESULTS 4D-PET increased LRLG ( = 1%-2%, p < 0.02), Busyness ( = 7%-19%, p < 0.01), and decreased MCC ( = 1%-2%, p < 7.5 × 10(-3)), Coarseness ( = 5%-10%, p < 0.05) and Contrast ( = 4%-6%, p > 0.08) compared to 3D-PET. Nearly negligible variability was found between the 4D phase bins with CV < 5% for MCC, LRLG, and Coarseness. For Contrast and Busyness, moderate variability was found with CV = 9% and 10%, respectively. No strong correlation was found between the tumor volume and δ3D-4D for the texture features. Motion amplitude had moderate impact on δ for MCC and Busyness and no impact for LRLG, Coarseness, and Contrast. CONCLUSIONS Significant differences were found in MCC, LRLG, Coarseness, and Busyness between 3D and 4D PET imaging. The variability between phase bins for MCC, LRLG, and Coarseness was negligible, suggesting that similar quantification can be obtained from all phases. Texture features, blurred out by respiratory motion during 3D-PET acquisition, can be better resolved by 4D-PET imaging. 4D-PET textures may have better prognostic value as they are less susceptible to tumor motion.
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Affiliation(s)
- Stephen Yip
- Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
| | - Keisha McCall
- Department of Radiology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Michalis Aristophanous
- Department of Radiation Physics, Division of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Aileen B. Chen
- Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Hugo J. W. L. Aerts
- Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
- Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ross Berbeco
- Department of Radiation Oncology, Brigham and Women's Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts, United States of America
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Mori S, Inaniwa T, Furukawa T, Takahashi W, Nakajima M, Shirai T, Noda K, Yasuda S, Yamamoto N. Amplitude-based gated phase-controlled rescanning in carbon-ion scanning beam treatment planning under irregular breathing conditions using lung and liver 4DCTs. J Radiat Res 2014; 55:948-958. [PMID: 24835238 PMCID: PMC4202290 DOI: 10.1093/jrr/rru032] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 02/26/2014] [Accepted: 04/01/2014] [Indexed: 05/29/2023]
Abstract
Amplitude-based gating aids treatment planning in scanned particle therapy because it gives better control of uncertainty with the gate window. We have installed an X-ray fluoroscopic imaging system in our treatment room for clinical use with an amplitude-based gating strategy. We evaluated the effects of this gating under realistic organ motion conditions using 4 DCT data of lung and liver tumors. 4 DCT imaging was done for 24 lung and liver patients using the area-detector CT. We calculated the field-specific target volume (FTV) for the gating window, which was defined for a single respiratory cycle. Prescribed doses of 48 Gy relative biological effectiveness (RBE)/fraction/four fields and 45 Gy RBE/two fractions/two fields were delivered to the FTVs for lung and liver treatments, respectively. Dose distributions were calculated for the repeated first respiratory cycle (= planning dose) and the whole respiratory data (= treatment dose). We applied eight phase-controlled rescannings with the amplitude-based gating. For the lung cases, D95 of the treatment dose (= 96.0 ± 1.0%) was almost the same as that of the planning dose (= 96.6 ± 0.9%). D(max)/D(min) of the treatment dose (= 104.5 ± 2.2%/89.4 ± 2.6%) was slightly increased over that of the planning dose (= 102.1 ± 1.0%/89.8 ± 2.5%) due to hot spots. For the liver cases, D95 of the treatment dose (= 97.6 ± 0.5%) was decreased by ∼ 1% when compared with the planning dose (= 98.5 ± 0.4%). D(max)/D(min) of the treatment dose was degraded by 3.0%/0.4% compared with the planning dose. Average treatment times were extended by 46.5 s and 65.9 s from those of the planning dose for lung and liver cases, respectively. As with regular respiratory patterns, amplitude-based gated multiple phase-controlled rescanning preserves target coverage to a moving target under irregular respiratory patterns.
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Affiliation(s)
- Shinichiro Mori
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Taku Inaniwa
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Takuji Furukawa
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Wataru Takahashi
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Mio Nakajima
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Toshiyuki Shirai
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Koji Noda
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Shigeo Yasuda
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
| | - Naoyoshi Yamamoto
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Inage-ku, Chiba 263-8555, Japan
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Weiger M, Wu M, Wurnig MC, Kenkel D, Jungraithmayr W, Boss A, Pruessmann KP. Rapid and robust pulmonary proton ZTE imaging in the mouse. NMR Biomed 2014; 27:1129-1134. [PMID: 25066371 DOI: 10.1002/nbm.3161] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 06/17/2014] [Accepted: 06/17/2014] [Indexed: 06/03/2023]
Abstract
Pulmonary MRI is challenging because of the low proton density and rapid transverse relaxation in the lung associated with microscopic magnetic field inhomogeneities caused by tissue-air interfaces. Therefore, low signal is obtained in gradient and spin echo proton images. Alternatively, non-proton MRI using hyperpolarized gases or radial techniques with ultrashort or zero TE have been proposed to image the lung. Also with the latter approach, the general challenge remains to provide full coverage of the lung at sufficient spatial resolution, signal-to-noise ratio (SNR) and image quality within a reasonable scan time. This task is further aggravated by physiological motion and is particularly demanding in small animals, such as mice. In this work, three-dimensional (3D) zero echo time (ZTE) imaging is employed for efficient pulmonary MRI. Four protocols with different averaging and respiratory triggering schemes are developed and compared with respect to image quality and SNR. To address the critical issue of background signal in ZTE images, a subtraction approach is proposed, providing images virtually free of disturbing signal from nearby hardware parts. The protocols are tested for pulmonary MRI in six mice at 4.7 T, consistently providing images of high quality with a 3D isotropic resolution of 313 µm and SNR values in the lung between 8.0 and 18.5 within scan times between 1 min 21 s and 4 min 44 s. A generally high robustness of the ZTE approach against motion is observed, whilst respiratory triggering further improves the SNR and visibility of image details. The developed techniques are expected to enable efficient preclinical animal studies in the lung and will also be of importance for human applications. Further improvements are expected from radiofrequency (RF) coils with increased SNR and reduced background signal.
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Affiliation(s)
- Markus Weiger
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland
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Huang TC, Chou KT, Wang YC, Zhang G. Motion freeze for respiration motion correction in PET/CT: a preliminary investigation with lung cancer patient data. Biomed Res Int 2014; 2014:167491. [PMID: 25250313 PMCID: PMC4164623 DOI: 10.1155/2014/167491] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 08/13/2014] [Accepted: 08/16/2014] [Indexed: 11/17/2022]
Abstract
PURPOSE Respiratory motion presents significant challenges for accurate PET/CT. It often introduces apparent increase of lesion size, reduction of measured standardized uptake value (SUV), and the mismatch in PET/CT fusion images. In this study, we developed the motion freeze method to use 100% of the counts collected by recombining the counts acquired from all phases of gated PET data into a single 3D PET data, with correction of respiration by deformable image registration. METHODS Six patients with diagnosis of lung cancer confirmed by oncologists were recruited. PET/CT scans were performed with Discovery STE system. The 4D PET/CT with the Varian real-time position management for respiratory motion tracking was followed by a clinical 3D PET/CT scan procedure in the static mode. Motion freeze applies the deformation matrices calculated by optical flow method to generate a single 3D effective PET image using the data from all the 4D PET phases. RESULTS The increase in SUV and decrease in tumor size with motion freeze for all lesions compared to the results from 3D and 4D was observed in the preliminary data of lung cancer patients. In addition, motion freeze substantially reduced tumor mismatch between the CT image and the corresponding PET images. CONCLUSION Motion freeze integrating 100% of the PET counts has the potential to eliminate the influences induced by respiratory motion in PET data.
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Affiliation(s)
- Tzung-Chi Huang
- Department of Biomedical Imaging and Radiological Science, China Medical University, 91 Hsueh-Shih Road, Taichung City, Taiwan
- Department of Biomedical Informatics, Asia University, Taichung City, Taiwan
| | - Kuei-Ting Chou
- Department of Biomedical Imaging and Radiological Science, China Medical University, 91 Hsueh-Shih Road, Taichung City, Taiwan
| | - Yao-Ching Wang
- Department of Radiation Oncology, China Medical University Hospital, Taichung City, Taiwan
| | - Geoffrey Zhang
- Department of Radiation Oncology, Moffitt Cancer Center, Tampa, FL, USA
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Hanneman K, Sivagnanam M, Nguyen ET, Wald R, Greiser A, Crean AM, Ley S, Wintersperger BJ. Magnetic resonance assessment of pulmonary (QP) to systemic (QS) flows using 4D phase-contrast imaging: pilot study comparison with standard through-plane 2D phase-contrast imaging. Acad Radiol 2014; 21:1002-8. [PMID: 25018072 DOI: 10.1016/j.acra.2014.04.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 04/16/2014] [Accepted: 04/16/2014] [Indexed: 01/25/2023]
Abstract
RATIONALE AND OBJECTIVES To investigate four-dimensional (4D) phase-contrast (PC) magnetic resonance (MR) in the evaluation of intracardiac shunts by simultaneous assessment of pulmonary (QP) and systemic (QS) flows in a pilot study and to compare results to through-plane two-dimensional (2D) PC MR. MATERIALS AND METHODS Institutional review board approval and written informed consent were obtained. Nineteen patients with suspected intracardiac shunts underwent cardiac MR at 1.5T. Assessments of QP and QS were performed using free-breathing retrospectively gated 2D PC gradient recalled echo (GRE; 1.6 × 1.6 × 5 mm(3)) imaging with one-dimensional through-plane velocity encoding gradient (venc = 150 cm/s) in consecutive measurements for the main pulmonary artery (MPA) and ascending aorta (AA), respectively. A prospectively triggered 4D PC GRE technique (2.4 × 1.8 × 3 mm(3)) with three orthogonal venc directions was also used with volume coverage of both MPA and AA. RESULTS QP and QS assessed by 4D PC correlated with 2D PC acquisitions (r = 0.92 and r = 0.67 respectively; P < .0001 for both) but demonstrated significant underestimation of individual flow volumes (-21.9 ± 12.2 mL; P < .0001 and -10.7 ± 13.1 mL; P = .0023, respectively). Calculated QP:QS ratios demonstrated high correlation (r = 0.78; P < .0001) and no significant differences between 4D PC and 2D PC acquisitions (-0.09 ± 0.24, P = .14). Image acquisition times for 2D PC assessment of QP and QS were 2.98 ± 0.52 and 2.84 ± 0.50 minutes, respectively (P = .038), whereas time to acquire 4D PC images was significantly longer, 18.75 ± 4.58 minutes (P < .001). CONCLUSIONS Four-dimensional PC MR imaging allows for accurate assessment of QP:QS ratios in the evaluation of intracardiac shunts while absolute flow volumes demonstrate offsets. Further refinement of the technique with improvement in acquisition times may be required before widespread clinical implementation.
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Affiliation(s)
- Kate Hanneman
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada
| | - Milani Sivagnanam
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada
| | - Elsie T Nguyen
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada
| | - Rachel Wald
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada; Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | | | - Andrew M Crean
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada; Division of Cardiology, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, Toronto, Ontario, Canada
| | - Sebastian Ley
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada
| | - Bernd J Wintersperger
- Department of Medical Imaging, Peter Munk Cardiac Centre, Toronto General Hospital, University Health Network, University of Toronto, 585 University Ave, Toronto, Ontario M5G 2N2, Canada.
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Castillo SJ, Castillo R, Balter P, Pan T, Ibbott G, Hobbs B, Yuan Y, Guerrero T. Assessment of a quantitative metric for 4D CT artifact evaluation by observer consensus. J Appl Clin Med Phys 2014; 15:4718. [PMID: 24892346 PMCID: PMC4048877 DOI: 10.1120/jacmp.v15i3.4718] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 01/28/2014] [Accepted: 01/06/2014] [Indexed: 12/12/2022] Open
Abstract
The benefits of four-dimensional computed tomography (4D CT) are limited by the presence of artifacts that remain difficult to quantify. A correlation-based metric previously proposed for ciné 4D CT artifact identification was further validated as an independent artifact evaluator by using a novel qualitative assessment featuring a group of observers reaching a consensus decision on artifact location and magnitude. The consensus group evaluated ten ciné 4D CT scans for artifacts over each breathing phase of coronal lung views assuming one artifact per couch location. Each artifact was assigned a magnitude score of 1-5, 1 indicating lowest severity and 5 indicating highest severity. Consensus group results served as the ground truth for assessment of the correlation metric. The ten patients were split into two cohorts; cohort 1 generated an artifact identification threshold derived from receiver operating characteristic analysis using the Youden Index, while cohort 2 generated sensitivity and specificity values from application of the artifact threshold. The Pearson correlation coefficient was calculated between the correlation metric values and the consensus group scores for both cohorts. The average sensitivity and specificity values found with application of the artifact threshold were 0.703 and 0.476, respectively. The correlation coefficients of artifact magnitudes for cohort 1 and 2 were 0.80 and 0.61, respectively, (p < 0.001 for both); these correlation coefficients included a few scans with only two of the five possible magnitude scores. Artifact incidence was associated with breathing phase (p < 0.002), with presentation less likely near maximum exhale. Overall, the correlation metric allowed accurate and automated artifact identification. The consensus group evaluation resulted in efficient qualitative scoring, reduced interobserver variation, and provided consistent identification of artifact location and magnitudes.
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Lin H, Lu H, Shu L, Huang H, Chen H, Chen J, Cheng J, Pang Q, Peng L, Gu J, Lu Z. Dosimetric study of a respiratory gating technique based on four-dimensional computed tomography in non-small-cell lung cancer. J Radiat Res 2014; 55:583-588. [PMID: 24453355 PMCID: PMC4014168 DOI: 10.1093/jrr/rrt145] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 11/15/2013] [Accepted: 11/27/2013] [Indexed: 06/03/2023]
Abstract
This study sought to compare the differences in target volumes and dose distributions to the targets and organs at risk (OARs) between a four-dimensional computed tomography (4DCT)-based respiratory-gated intensity-modulated radiation therapy (IMRT) plan (PlanEOE) and a three-dimensional CT (3DCT)-based IMRT plan (Plan3D) in patients with non-small-cell lung cancer (NSCLC). For 17 patients with Stages I-III NSCLC, both 4DCT data and conventional 3DCT data were obtained. The Plan3D and PlanEOE were designed based on 3DCT data and 4DCT data, respectively. The displacements of the gross tumor volume (GTV) centroid were 0.13 ± 0.09 cm, 0.15 ± 0.1 cm, and 0.27 ± 0.27 cm in the right-left, anterior-posterior, and superior-inferior directions, respectively. The volume of the GTVEOE was 3.05 ± 5.17 cm(3) larger than that of the GTV3D. The volume of the PTV3D was 72.82 ± 48.65 cm(3) larger than that of the PTVEOE. There was no significant difference between the PTV3D and PTVEOE for V55.8, V60, V66 and the homogeneity index. The PTV3D had a lower target conformity index than the PTVEOE (P = 0.036). PlanEOE had a significantly lower lung V10, V20, V30, V40 and mean lung dose (MLD) than Plan3D. For the heart, PlanEOE had a significantly lower V30 and mean dose. In conclusion, 4DCT is an appropriate method for assessing the displacement of the GTV centroid in three dimensions. PlanEOE has smaller PTVs and a decreased dose and volume for the normal lung and heart, as compared with Plan3D.
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Affiliation(s)
- Hui Lin
- Department of Thoracic Surgery, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Heming Lu
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Liuyang Shu
- Department of Medical Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Huixian Huang
- Department of Clinical Medicine, Guangxi Medical University, 22 Shuangyong Road, Nanning 530021, China
| | - Huasheng Chen
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Jiaxin Chen
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Jinjian Cheng
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Qiang Pang
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Luxing Peng
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Junzhao Gu
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
| | - Zhiping Lu
- Department of Radiation Oncology, People's Hospital of Guangxi Zhuang Autonomous Region, 6 Taoyuan Road, Nanning City, 530021, Guangxi, China
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Yao X, Kuang T, Wu L, Feng H, Liu H, Cheng W, Rao S, Wang H, Zeng M. Optimization of MR diffusion-weighted imaging acquisitions for pancreatic cancer at 3.0T. Magn Reson Imaging 2014; 32:875-9. [PMID: 24848293 DOI: 10.1016/j.mri.2014.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 03/03/2014] [Accepted: 04/15/2014] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To investigate and optimize diffusion-weighted imaging (DWI) acquisitions for pancreatic cancer at 3.0T. METHODS Forty-five patients with pancreatic cancer were examined by four DWI acquisitions with b values=0 and 600s/mm(2) at 3.0T, including breath-holding DWI (BH-DWI), respiratory-triggered DWI (TRIG-DWI), respiratory-triggered DWI with inversion-recovery technique (TRIGIR-DWI), and free-breathing DWI with inversion-recovery technique (FBIR-DWI). Artifacts, contrast ratio (CR), contrast-to-noise ratio (CNR) and apparent diffusion coefficient (ADC) of pancreatic cancer were statistically compared among DWI acquisitions. RESULTS TRIGIR-DWI displayed the lowest artifacts and highest CR compared to other DWI acquisitions. CNRs of pancreatic cancer in TRIG-DWI and TRIGIR-DWI were statistically higher than that in FBIR-DWI and BH-DWI. Different ADCs between pancreatic cancer and noncancerous pancreatic tissues were noticed by a paired-samples T test in TRIG-DWI (p=0.017), TRIGIR-DWI (p=0.00001) and FBIR-DWI (p=0.000041). CONCLUSIONS TRIGIR-DWI may be the optimal acquisition of DWI for pancreatic cancer at 3.0T.
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Affiliation(s)
- Xiuzhong Yao
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Tiantao Kuang
- Department of General Surgery, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Li Wu
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Hao Feng
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Hao Liu
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Weizhong Cheng
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - Shengxiang Rao
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
| | - He Wang
- Global Applied Science Laboratory of GE Healthcare, No. 1, Huatuo Road, Zhangjiang Hi-tech Park, Pudong District, Shanghai 201203, China.
| | - Mengsu Zeng
- Department of Radiology, Zhongshan Hospital of Fudan University, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China; Department of Medical Image, Shanghai Medical College of Fudan University, Shanghai Institute of Medical Imaging, No. 138, Fenglin Road, Xuhui District, Shanghai 200032, China.
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Christofides D, Leen E, Averkiou M. Automatic respiratory gating for contrast ultrasound evaluation of liver lesions. IEEE Trans Ultrason Ferroelectr Freq Control 2014; 61:25-32. [PMID: 24402893 DOI: 10.1109/tuffc.2014.6689773] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Dynamic contrast-enhanced ultrasound (DCEUS) has been used in radiology for many years for lesion detection and characterization. In recent years, more emphasis has been placed on tumor perfusion quantification with DCEUS. To ensure accuracy in both quantitative and qualitative evaluation of liver tumors with DCEUS, sources of noise in clinical data must be identified and, if possible, removed. One of the major sources of such noise is respiratory motion. A new automatic respiratory gating (ARG) algorithm is presented and evaluated with clinical data. The results of the evaluation demonstrate the potential of the ARG algorithm for clinical use as a fast and easy-to-implement method for removing respiratory motion from DCEUS loops.
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