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Secerov Ermenc A, Segedin B. The Role of MRI and PET/CT in Radiotherapy Target Volume Determination in Gastrointestinal Cancers-Review of the Literature. Cancers (Basel) 2023; 15:cancers15112967. [PMID: 37296929 DOI: 10.3390/cancers15112967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/22/2023] [Accepted: 05/25/2023] [Indexed: 06/12/2023] Open
Abstract
Positron emission tomography with computed tomography (PET/CT) and magnetic resonance imaging (MRI) could improve accuracy in target volume determination for gastrointestinal cancers. A systematic search of the PubMed database was performed, focusing on studies published within the last 20 years. Articles were considered eligible for the review if they included patients with anal canal, esophageal, rectal or pancreatic cancer, as well as PET/CT or MRI for radiotherapy treatment planning, and if they reported interobserver variability or changes in treatment planning volume due to different imaging modalities or correlation between the imaging modality and histopathologic specimen. The search of the literature retrieved 1396 articles. We retrieved six articles from an additional search of the reference lists of related articles. Forty-one studies were included in the final review. PET/CT seems indispensable for target volume determination of pathological lymph nodes in esophageal and anal canal cancer. MRI seems appropriate for the delineation of primary tumors in the pelvis as rectal and anal canal cancer. Delineation of the target volumes for radiotherapy of pancreatic cancer remains challenging, and additional studies are needed.
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Affiliation(s)
- Ajra Secerov Ermenc
- Department of Radiation Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Barbara Segedin
- Department of Radiation Oncology, Institute of Oncology Ljubljana, 1000 Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia
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2
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Chuong MD, Palm RF, Tjong MC, Hyer DE, Kishan AU. Advances in MRI-Guided Radiation Therapy. Surg Oncol Clin N Am 2023; 32:599-615. [PMID: 37182995 DOI: 10.1016/j.soc.2023.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Image guidance for radiation therapy (RT) has evolved over the last few decades and now is routinely performed using cone-beam computerized tomography (CBCT). Conventional linear accelerators (LINACs) that use CBCT have limited soft tissue contrast, are not able to image the patient's internal anatomy during treatment delivery, and most are not capable of online adaptive replanning. RT delivery systems that use MRI have become available within the last several years and address many of the imaging limitations of conventional LINACs. Herein, the authors review the technical characteristics and advantages of MRI-guided RT as well as emerging clinical outcomes.
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Affiliation(s)
- Michael D Chuong
- Department of Radiation Oncology, Miami Cancer Institute, 8900 North Kendall Drive, Miami, FL 33176, USA.
| | - Russell F Palm
- Department of Radiation Oncology, Moffitt Cancer Center, 12902 USF Magnolia Drive, Tampa, FL 33612, USA
| | - Michael C Tjong
- Department of Radiation Oncology, Dana-Farber Cancer Institute, 450 Brookline Avenue, Boston, MA 02215, USA
| | - Daniel E Hyer
- Department of Radiation Oncology, University of Iowa, 200 Hawkins Dr, Iowa City, IA 52242, USA
| | - Amar U Kishan
- Department of Radiation Oncology, University of California Los Angeles, 1338 S Hope Street, Los Angeles, CA 90015, USA
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3
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Srinivasan S, Dasgupta A, Chatterjee A, Baheti A, Engineer R, Gupta T, Murthy V. The Promise of Magnetic Resonance Imaging in Radiation Oncology Practice in the Management of Brain, Prostate, and GI Malignancies. JCO Glob Oncol 2022; 8:e2100366. [PMID: 35609219 PMCID: PMC9173575 DOI: 10.1200/go.21.00366] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Magnetic resonance imaging (MRI) has a key role to play at multiple steps of the radiotherapy (RT) treatment planning and delivery process. Development of high-precision RT techniques such as intensity-modulated RT, stereotactic ablative RT, and particle beam therapy has enabled oncologists to escalate RT dose to the target while restricting doses to organs at risk (OAR). MRI plays a critical role in target volume delineation in various disease sites, thus ensuring that these high-precision techniques can be safely implemented. Accurate identification of gross disease has also enabled selective dose escalation as a means to widen the therapeutic index. Morphological and functional MRI sequences have also facilitated an understanding of temporal changes in target volumes and OAR during a course of RT, allowing for midtreatment volumetric and biological adaptation. The latest advancement in linear accelerator technology has led to the incorporation of an MRI scanner in the treatment unit. MRI-guided RT provides the opportunity for MRI-only workflow along with online adaptation for either target or OAR or both. MRI plays a key role in post-treatment response evaluation and is an important tool for guiding decision making. In this review, we briefly discuss the RT-related applications of MRI in the management of brain, prostate, and GI malignancies.
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Affiliation(s)
- Shashank Srinivasan
- Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
| | - Archya Dasgupta
- Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
| | - Abhishek Chatterjee
- Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
| | - Akshay Baheti
- Department of Radiodiagnosis, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
| | - Reena Engineer
- Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
| | - Tejpal Gupta
- Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
| | - Vedang Murthy
- Department of Radiation Oncology, Tata Memorial Centre, Homi Bhabha National Institute, Mumbai, India
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4
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Omari EA, Zhang Y, Ahunbay E, Paulson E, Amjad A, Chen X, Liang Y, Li XA. Multi parametric magnetic resonance imaging for radiation treatment planning. Med Phys 2022; 49:2836-2845. [PMID: 35170769 DOI: 10.1002/mp.15534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 10/05/2021] [Accepted: 01/03/2022] [Indexed: 11/09/2022] Open
Abstract
In recent years, multi-parametric magnetic resonance imaging (MpMRI) has played a major role in radiation therapy treatment planning. The superior soft tissue contrast, functional or physiological imaging capabilities and the flexibility of site-specific image sequence development has placed MpMRI at the forefront. In this article, the present status of MpMRI for external beam radiation therapy planning is reviewed. Common MpMRI sequences, preprocessing and QA strategies are briefly discussed, and various image registration techniques and strategies are addressed. Image segmentation methods including automatic segmentation and deep learning techniques for organs at risk and target delineation are reviewed. Due to the advancement in MRI guided online adaptive radiotherapy, treatment planning considerations addressing MRI only planning are also discussed. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Eenas A Omari
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Ying Zhang
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Ergun Ahunbay
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Eric Paulson
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Asma Amjad
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Xinfeng Chen
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Ying Liang
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - X Allen Li
- Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
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5
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FDG-PET/CT and MR imaging for target volume delineation in rectal cancer radiotherapy treatment planning: a systematic review. JOURNAL OF RADIOTHERAPY IN PRACTICE 2021. [DOI: 10.1017/s1460396921000388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Abstract
Aim:
The aim of this systematic review was to synthesise and summarise evidence surrounding the clinical use of fluoro-2-deoxy-d-glucose positron emission tomography/computed tomography (FDG-PET/CT) and magnetic resonance imaging (MRI) for target volume delineation (TVD) in rectal cancer radiotherapy planning.
Methods:
PubMed, EMBASE, Cochrane library, CINAHL, Web of Science and Scopus databases and other sources were systematically queried using keywords and relevant synonyms. Eligible full-text studies were assessed for methodological quality using the QUADAS-2 tool.
Results:
Eight of the 1448 studies identified met the inclusion criteria. Findings showed that MRI significantly delineate larger tumour volumes (TVs) than FDG-PET/CT while diffusion-weighted magnetic resonance imaging (DW-MRI) defined smaller gross tumour volumes (GTVs) compared to T2 weighted-Magnetic Resonance Image. CT-based GTVs were found to be larger compared to FDG-PET/CT. FDG-PET/CT also identified new lesions in 15–17% patients and TVs extending outside the routinely used clinical standard CT TV in 29–83% patients. Between observers, delineated volumes were similar and consistent between MRI sequences, whereas interobserver agreement was significantly improved with FDG-PET/CT than CT.
Conclusion:
FDG-PET/CT and DW-MRI appear to delineate smaller rectal TVs and show improved interobserver variability. Overall, this study provides valuable insights into the amount of attention in the research literature that has been paid to imaging for TVD in rectal cancer.
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Liu J, Chen M, Li Z, Sun Y, Wang H, Wang Y. Application of titanium clip marking in localization of 37 cases of rectal cancer before radiotherapy. PRECISION RADIATION ONCOLOGY 2020. [DOI: 10.1002/pro6.1090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Jin‐qi Liu
- Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences Jinan China
| | - Ming Chen
- Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences Jinan China
| | - Zeng‐jun Li
- Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences Jinan China
| | - Yong‐min Sun
- Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences Jinan China
| | - Hai‐peng Wang
- Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences Jinan China
| | - Ya‐wei Wang
- Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical Sciences Jinan China
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7
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Randrian V, Biau J, Benoît C, Pezet D, Lapeyre M, Moreau J. [Preoperative intensity-modulated radiotherapy of rectal cancers: Relevance and modalities]. Cancer Radiother 2020; 24:345-353. [PMID: 32360094 DOI: 10.1016/j.canrad.2019.11.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 10/27/2019] [Accepted: 11/06/2019] [Indexed: 12/18/2022]
Abstract
Preoperative radiotherapy boosted by chemotherapy is a recommended treatment in locally advanced rectal cancers. This treatment is delivered by three dimensional conformal irradiation, which is usually well tolerated but can induce potential toxicity such as rectitis, cystitis and hematologic adverse effects. Intensity-modulated radiotherapy, widely available nowadays, allows optimization of volume covering and sparing of organs at risk such as bladder and bone marrow. This review presents relevant clinical situations and requirements for a beneficial and safe preoperative irradiation of rectal cancers by intensity-modulated technique. This technique is compared to three-dimensional conformal radiotherapy.
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Affiliation(s)
- V Randrian
- Département de médecine digestive et hépatobiliaire, CHU de l'hôpital Estaing, 63003 Clermont-Ferrand cedex 1, France
| | - J Biau
- Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1, France
| | - C Benoît
- Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1, France
| | - D Pezet
- Département de chirurgie digestive et hépatobiliaire, CHU de l'hôpital Estaing, 63003 Clermont-Ferrand cedex 1, France
| | - M Lapeyre
- Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1, France
| | - J Moreau
- Département de radiothérapie, centre Jean-Perrin, 58, rue Montalembert, BP 5026, 63011 Clermont-Ferrand cedex 1, France.
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8
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van den Ende RPJ, Kerkhof EM, Rigter LS, van Leerdam ME, Peters FP, van Triest B, Staring M, Marijnen CAM, van der Heide UA. Feasibility of Gold Fiducial Markers as a Surrogate for Gross Tumor Volume Position in Image-Guided Radiation Therapy of Rectal Cancer. Int J Radiat Oncol Biol Phys 2019; 105:1151-1159. [PMID: 31476419 DOI: 10.1016/j.ijrobp.2019.08.052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 08/16/2019] [Accepted: 08/26/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE To evaluate the feasibility of fiducial markers as a surrogate for gross tumor volume (GTV) position in image-guided radiation therapy of rectal cancer. METHODS AND MATERIALS We analyzed 35 fiducials in 19 patients with rectal cancer who received short-course radiation therapy or long-course chemoradiation therapy. Magnetic resonance imaging examinations were performed before and after the first week of radiation therapy, and daily pre- and postirradiation cone beam computed tomography scans were acquired in the first week of radiation therapy. Between the 2 magnetic resonance imaging examinations, the fiducial displacement relative to the center of gravity of the GTV (COGGTV) and the COGGTV displacement relative to bony anatomy were determined. Using the cone beam computed tomography scans, inter- and intrafraction fiducial displacement relative to bony anatomy were determined. RESULTS The systematic error of the fiducial displacement relative to the COGGTV was 2.8, 2.4, and 4.2 mm in the left-right, anterior-posterior (AP), and craniocaudal (CC) directions, respectively. Large interfraction systematic errors of up to 8.0 mm and random errors up to 4.7 mm were found for COGGTV and fiducial displacements relative to bony anatomy, mostly in the AP and CC directions. For tumors located in the mid and upper rectum, these errors were up to 9.4 mm (systematic) and 5.6 mm (random) compared with 4.9 mm and 2.9 mm for tumors in the lower rectum. Systematic and random errors of the intrafraction fiducial displacement relative to bony anatomy were ≤2.1 mm in all directions. CONCLUSIONS Large interfraction errors of the COGGTV and the fiducials relative to bony anatomy were found. Therefore, despite the observed fiducial displacement relative to the COGGTV, the use of fiducials as a surrogate for GTV position reduces the required margins in the AP and CC directions for a GTV boost using image-guided radiation therapy of rectal cancer. This reduction in margin may be larger in patients with tumors located in the mid and upper rectum compared with the lower rectum.
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Affiliation(s)
- Roy P J van den Ende
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands.
| | - Ellen M Kerkhof
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Lisanne S Rigter
- Department of Gastroenterology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Monique E van Leerdam
- Department of Gastroenterology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Femke P Peters
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Baukelien van Triest
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Marius Staring
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands; Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Corrie A M Marijnen
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Uulke A van der Heide
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands; Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands
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9
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Hassan M, Murtza I, Hira A, Ali S, Kifayat K. Robust spatial fuzzy GMM based MRI segmentation and carotid artery plaque detection in ultrasound images. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2019; 175:179-192. [PMID: 31104706 DOI: 10.1016/j.cmpb.2019.04.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/27/2019] [Accepted: 04/22/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND AND OBJECTIVE In medical image analysis for disease diagnosis, segmentation is one of the challenging tasks. Owing to the inherited degradations in MRI improper segments are produced. Segmentation process is an important step in brain tissue analysis. Moreover, an early detection of plaque in carotid artery using ultrasound images may prevent serious brain strokes. Unfortunately, low quality and noisy ultrasound images are still challenges for accurate segmentation. The objective of this research is to develop a robust segmentation approach for medical images such as brain MRI and carotid artery ultrasound images. METHODS In this paper, a novel approach is proposed to address the segmentation challenges of medical images. The proposed approach employed fuzzy intelligence and Gaussian mixture model (GMM). It comprises two phases; firstly, incorporating spatial fuzzy c-means in GMM by exploiting statistical, texture, and wavelet image features. During model development, GMM parameters are estimated in presence of noise by EM algorithm iteratively. Utilizing these parameters, brain MRI images are segmented. In next phase, developed approach is applied to solve a real problem of carotid artery plaque detection using ultrasound images. The dataset of real patients annotated by radiologists has been obtained from Radiology Department, Shifa International Hospital Islamabad, Pakistan. For this, intima-media-thickness values are computed from the proposed segmentation followed by support vector machines for plaque classification (normal/abnormal). RESULTS The obtained segmentation has been evaluated on standard brain MRI dataset and offers high segmentation accuracy of 99.2%. The proposed approach outperforms in term of segmentation performance range of 3-9% as compared to the state of the art approaches on brain MRI. Furthermore, the proposed approach shows robustness to various levels of Gaussian and Rician image noises. On carotid artery dataset, we have obtained high plaque detection rate in terms of accuracy, sensitivity, specificity, and F-score values of 98.8%, 99.3%, 98.0%, and 97.5% respectively. CONCLUSIONS The proposed approach segments both modalities with high precision and shows robustness at Gaussian and Rician noise levels. Results for brain MRI and ultrasound images indicate its effectiveness and can be used as second opinion in addition to the radiologists. The developed approach is straightforward, efficient, and reproducible. It may benefit to improve the clinical evaluation of the disease in both asymptomatic and symptomatic individuals.
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Affiliation(s)
- Mehdi Hassan
- Department of Computer Science, Air University Sector E-9, PAF Complex, Islamabad, Pakistan.
| | - Iqbal Murtza
- Department of Computer Science, Air University Sector E-9, PAF Complex, Islamabad, Pakistan
| | - Aysha Hira
- Department of Computer Science, Air University Sector E-9, PAF Complex, Islamabad, Pakistan
| | - Safdar Ali
- Directorate General National Repository, Islamabad, Pakistan
| | - Kashif Kifayat
- Department of Computer Science, Air University Sector E-9, PAF Complex, Islamabad, Pakistan
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10
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White IM, Scurr E, Wetscherek A, Brown G, Sohaib A, Nill S, Oelfke U, Dearnaley D, Lalondrelle S, Bhide S. Realizing the potential of magnetic resonance image guided radiotherapy in gynaecological and rectal cancer. Br J Radiol 2019; 92:20180670. [PMID: 30933550 PMCID: PMC6592079 DOI: 10.1259/bjr.20180670] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 02/24/2019] [Accepted: 03/21/2019] [Indexed: 12/25/2022] Open
Abstract
CT-based radiotherapy workflow is limited by poor soft tissue definition in the pelvis and reliance on rigid registration methods. Current image-guided radiotherapy and adaptive radiotherapy models therefore have limited ability to improve clinical outcomes. The advent of MRI-guided radiotherapy solutions provides the opportunity to overcome these limitations with the potential to deliver online real-time MRI-based plan adaptation on a daily basis, a true "plan of the day." This review describes the application of MRI guided radiotherapy in two pelvic tumour sites likely to benefit from this approach.
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Affiliation(s)
- Ingrid M White
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Erica Scurr
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Andreas Wetscherek
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Gina Brown
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Aslam Sohaib
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Simeon Nill
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Uwe Oelfke
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - David Dearnaley
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Susan Lalondrelle
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
| | - Shreerang Bhide
- Institute of Cancer Research and Royal Marsden National Health Service Foundation Trust, Sutton, Surrey, UK
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11
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Reproducibility of rectal tumor volume delineation using diffusion-weighted MRI: Agreement on volumes between observers. Cancer Radiother 2019; 23:216-221. [DOI: 10.1016/j.canrad.2018.10.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/01/2018] [Accepted: 10/12/2018] [Indexed: 12/28/2022]
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12
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Fatemi A, Kanakamedala MR, Yang CC, Morris B, Duggar WN, Vijayakumar S. Evaluation of the Geometric and Dosimetric Accuracy of Synthetic Computed Tomography Images for Magnetic Resonance Imaging-only Stereotactic Radiosurgery. Cureus 2019; 11:e4404. [PMID: 31245194 PMCID: PMC6559689 DOI: 10.7759/cureus.4404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Introduction Stereotactic radiosurgery (SRS) plans created using synthetic computed tomography (CT) images derived from magnetic resonance imaging (MRI) data may offer the advantage of inhomogeneity correction by convolution algorithms, as is done for CT-based plans. We sought to determine and validate the clinical significance and accuracy of synthetic CT images for inhomogeneity correction in MRI-only stereotactic radiosurgery plans for treatment of brain tumors. Methods In this retrospective study, data from two patients with brain metastases and one with meningioma who underwent imaging with multiple modalities and received frameless SRS treatment were analyzed. The SRS plans were generated using a convolution algorithm to account for brain inhomogeneity using CT and synthetic CT images and compared with the original clinical TMR10 plans created using MRI images. Results Synthetic CT-derived SRS plans are comparable with CT-based plans using convolution algorithm, and for some targets, based on location, they provided better coverage and a lower maximum dose. Conclusions The results suggest similar dose delivery results for CT and synthetic CT-based treatment plans. Synthetic CT plans offered a noticeable improvement in target dose coverage and a more gradual dose fall-off relative to TMR10 MRI-based plans. The major disadvantage is a slightly increased dose (by 0.37%) to nearby healthy tissue (brainstem) for synthetic CT-based plans relative to those created using clinical MRI images, which may be a problem for patients undergoing high-dose treatment.
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Affiliation(s)
- Ali Fatemi
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | | | - Claus Chunli Yang
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - Bart Morris
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
| | - William N Duggar
- Radiation Oncology, University of Mississippi Medical Center, Jackson, USA
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13
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Maspero M, Tyyger MD, Tijssen RH, Seevinck PR, Intven MP, van den Berg CA. Feasibility of magnetic resonance imaging-only rectum radiotherapy with a commercial synthetic computed tomography generation solution. PHYSICS & IMAGING IN RADIATION ONCOLOGY 2018; 7:58-64. [PMID: 33458406 PMCID: PMC7807733 DOI: 10.1016/j.phro.2018.09.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 09/15/2018] [Accepted: 09/20/2018] [Indexed: 12/14/2022]
Abstract
Background and purpose Synthetic computed tomography (sCT) images enable magnetic resonance (MR)-based dose calculations. This work investigated whether a commercially available sCT generation solution was suitable for accurate dose calculations and position verification on patients with rectal cancer. Material and methods For twenty rectal cancer patients computed tomography (CT) images were rigidly registered to sCT images. Clinical volumetric modulated arc therapy plans were recalculated on registered CT and sCT images. Dose deviations were determined through gamma and voxelwise analysis. The impact on position verification was investigated by identifying differences in translations and rotation between cone-beam CT (CBCT) to CT and CBCT to sCT registrations. Results Across twenty patients, within a threshold of 90% of the prescription dose, a gamma analysis (2%, 2 mm) mean pass rate of 95.2 ± 4.0% (±1σ) and mean dose deviation of −0.3 ± 0.2% of prescription dose were obtained. The mean difference of translations and rotations over ten patients (76 CBCTs) was <1 mm and <0.5° in all directions. In the sole posterior-anterior direction a mean systematic shift of 0.7 ± 0.6 mm was found. Conclusions Accurate MR-based dose calculations using a commercial sCT generation method were clinically feasible for treatment of rectal cancer patients. The accuracy of position verification was clinically acceptable. However, before clinical implementation future investigations will be performed to determine the origin of the systematic shift.
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Affiliation(s)
- Matteo Maspero
- Department of Radiotherapy, Universitair Medisch Centrum Utrecht, The Netherlands
- Center for Image Sciences, Universitair Medisch Centrum Utrecht, The Netherlands
- Corresponding author at: Department of Radiotherapy, Universitair Medisch Centrum Utrecht, Heidelberglaan 1003584 CX, Utrecht, The Netherlands.
| | - Marcus D. Tyyger
- Department of Radiotherapy, Universitair Medisch Centrum Utrecht, The Netherlands
- Leeds Teaching Hospital, Department of Medical Physics and Engineering, Leeds, United Kingdom
| | - Rob H.N. Tijssen
- Department of Radiotherapy, Universitair Medisch Centrum Utrecht, The Netherlands
| | - Peter R. Seevinck
- Center for Image Sciences, Universitair Medisch Centrum Utrecht, The Netherlands
- Image Science Institute, Universitair Medisch Centrum Utrecht, The Netherlands
| | - Martijn P.W. Intven
- Department of Radiotherapy, Universitair Medisch Centrum Utrecht, The Netherlands
| | - Cornelis A.T. van den Berg
- Department of Radiotherapy, Universitair Medisch Centrum Utrecht, The Netherlands
- Center for Image Sciences, Universitair Medisch Centrum Utrecht, The Netherlands
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14
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Pollard JM, Wen Z, Sadagopan R, Wang J, Ibbott GS. The future of image-guided radiotherapy will be MR guided. Br J Radiol 2017; 90:20160667. [PMID: 28256898 DOI: 10.1259/bjr.20160667] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Advances in image-guided radiotherapy (RT) have allowed for dose escalation and more precise radiation treatment delivery. Each decade brings new imaging technologies to help improve RT patient setup. Currently, the most frequently used method of three-dimensional pre-treatment image verification is performed with cone beam CT. However, more recent developments have provided RT with the ability to have on-board MRI coupled to the teleradiotherapy unit. This latest tool for treating cancer is known as MR-guided RT. Several varieties of these units have been designed and installed in centres across the globe. Their prevalence, history, advantages and disadvantages are discussed in this review article. In preparation for the next generation of image-guided RT, this review also covers where MR-guided RT might be heading in the near future.
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Affiliation(s)
| | - Zhifei Wen
- UT MD Anderson Cancer Center, Houston, TX, USA
| | | | - Jihong Wang
- UT MD Anderson Cancer Center, Houston, TX, USA
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15
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Robust segmentation and intelligent decision system for cerebrovascular disease. Med Biol Eng Comput 2016; 54:1903-1920. [DOI: 10.1007/s11517-016-1481-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 02/28/2016] [Indexed: 12/15/2022]
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16
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Burbach JPM, Kleijnen JPJ, Reerink O, Seravalli E, Philippens ME, Schakel T, van Asselen B, Raaymakers BW, van Vulpen M, Intven M. Inter-observer agreement of MRI-based tumor delineation for preoperative radiotherapy boost in locally advanced rectal cancer. Radiother Oncol 2016; 118:399-407. [DOI: 10.1016/j.radonc.2015.10.030] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 10/23/2015] [Accepted: 10/26/2015] [Indexed: 12/17/2022]
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17
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Teoh S, Muirhead R. Rectal Radiotherapy--Intensity-modulated Radiotherapy Delivery, Delineation and Doses. Clin Oncol (R Coll Radiol) 2015; 28:93-102. [PMID: 26643092 DOI: 10.1016/j.clon.2015.10.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 02/06/2023]
Abstract
The use of intensity-modulated radiotherapy in rectal cancer is attractive in that it may reduce acute and late toxicities and potentially facilitate dose escalation. Intensity-modulated radiotherapy probably has a role in selected patients, but further investigation is required to identify the parameters for selection. Delineation of specific nodal groups allows maximal sparing of bladder and small bowel. In locally advanced tumours a simultaneous integrated boost allows dose escalation incorporating hypofractionation and a shorter overall treatment time. However, due to a sparsity of data on late toxicity in doses ≥ 60 Gy, doses at this level should be used with caution, ideally within prospective trials. Future studies investigating dose escalation must ascertain late toxicity as well as local control, as both can significantly affect quality of life and without both, the risk-benefit ratio cannot be calculated.
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Affiliation(s)
- S Teoh
- Department of Oncology, Oxford University Hospitals Trust, Oxford, UK
| | - R Muirhead
- The Oxford Institute for Radiation Oncology, University of Oxford, Oxford, UK.
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Abstract
The use of magnetic resonance imaging (MRI) in radiotherapy (RT) planning is rapidly expanding. We review the wide range of image contrast mechanisms available to MRI and the way they are exploited for RT planning. However a number of challenges are also considered: the requirements that MR images are acquired in the RT treatment position, that they are geometrically accurate, that effects of patient motion during the scan are minimized, that tissue markers are clearly demonstrated, that an estimate of electron density can be obtained. These issues are discussed in detail, prior to the consideration of a number of specific clinical applications. This is followed by a brief discussion on the development of real-time MRI-guided RT.
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Affiliation(s)
- Maria A Schmidt
- Cancer Research UK Cancer Imaging Centre, Royal Marsden Hospital and the Institute of Cancer Research, Downs Road, Sutton, Surrey, SM2 5PT, UK
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19
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Prezzi D, Goh V. Rectal Cancer Magnetic Resonance Imaging: Imaging Beyond Morphology. Clin Oncol (R Coll Radiol) 2015; 28:83-92. [PMID: 26586163 DOI: 10.1016/j.clon.2015.10.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 10/13/2015] [Indexed: 12/16/2022]
Abstract
Magnetic resonance imaging (MRI) has in recent years progressively established itself as one of the most valuable modalities for the diagnosis, staging and response assessment of rectal cancer and its use has largely focused on accurate morphological assessment. The potential of MRI, however, extends beyond detailed anatomical depiction: aspects of tissue physiology, such as perfusion, oxygenation and water molecule diffusivity, can be assessed indirectly. Functional MRI is rapidly evolving as a promising non-invasive assessment tool for tumour phenotyping and assessment of response to new therapeutic agents. In spite of promising experimental data, the evidence base for the application of functional MRI techniques in rectal cancer remains modest, reflecting the relatively poor agreement on technical protocols, image processing techniques and quantitative methodology to date, hampering routine integration into clinical management. This overview outlines the established strengths and the critical limitations of anatomical MRI in rectal cancer; it then introduces some of the functional MRI techniques and quantitative analysis methods that are currently available, describing their applicability in rectal cancer and reviewing the relevant literature; finally, it introduces the concept of a multi-parametric quantitative approach to rectal cancer.
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Affiliation(s)
- D Prezzi
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK; Department of Radiology, Guy's and St Thomas' NHS Foundation Trust, London, UK.
| | - V Goh
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK; Department of Radiology, Guy's and St Thomas' NHS Foundation Trust, London, UK
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20
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Alam J, Hassan M, Khan A, Chaudhry A. Robust fuzzy RBF network based image segmentation and intelligent decision making system for carotid artery ultrasound images. Neurocomputing 2015. [DOI: 10.1016/j.neucom.2014.10.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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21
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Suarez-Gironzini V, Khoo V. Imaging Advances for Target Volume Definition in Radiotherapy. CURRENT RADIOLOGY REPORTS 2015. [DOI: 10.1007/s40134-015-0092-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Dirix P, Haustermans K, Vandecaveye V. The value of magnetic resonance imaging for radiotherapy planning. Semin Radiat Oncol 2015; 24:151-9. [PMID: 24931085 DOI: 10.1016/j.semradonc.2014.02.003] [Citation(s) in RCA: 104] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The success of highly conformal radiotherapy techniques in the sparing of normal tissues or in dose escalation, or both, relies heavily on excellent imaging. Because of its superior soft tissue contrast, magnetic resonance imaging is increasingly being used in radiotherapy treatment planning. This review discusses the current clinical evidence to support the pivotal role of magnetic resonance imaging in radiation oncology.
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Affiliation(s)
- Piet Dirix
- Department of Radiation Oncology, Leuvens Kankerinstituut (LKI), University Hospitals Leuven, Leuven, Belgium; Department of Radiology, Leuvens Kankerinstituut (LKI), University Hospitals Leuven, Leuven, Belgium.
| | - Karin Haustermans
- Department of Radiation Oncology, Leuvens Kankerinstituut (LKI), University Hospitals Leuven, Leuven, Belgium; Department of Oncology, KU Leuven, Leuven, Belgium
| | - Vincent Vandecaveye
- Department of Radiology, Leuvens Kankerinstituut (LKI), University Hospitals Leuven, Leuven, Belgium; Department of Imaging & Pathology, KU Leuven, Leuven, Belgium
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23
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Tan W, Han G, Wei S, Hu D. Sparing functional anatomical structures during intensity-modulated radiotherapy: an old problem, a new solution. Future Oncol 2014; 10:1863-72. [PMID: 23987920 DOI: 10.2217/fon.13.172] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
ABSTRACT During intensity-modulated radiotherapy, an organ is usually assumed to be functionally homogeneous and, generally, its anatomical and spatial heterogeneity with respect to radiation response are not taken into consideration. However, advances in imaging and radiation techniques as well as an improved understanding of the radiobiological response of organs have raised the possibility of sparing the critical functional structures within various organs at risk during intensity-modulated radiotherapy. Here, we discuss these structures, which include the critical brain structure, or neural nuclei, and the nerve fiber tracts in the CNS, head and neck structures related to radiation-induced salivary and swallowing dysfunction, and functional structures in the heart and lung. We suggest that these structures can be used as potential surrogate organs at risk in order to minimize their radiation dose and/or irradiated volume without compromising the dose coverage of the target volume during radiation treatment.
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Affiliation(s)
- Wenyong Tan
- Department of Radiation Oncology, Hubei Cancer Hospital, 116 South Road, Zhuodaoquan, Wuhan 430079, China
| | - Guang Han
- Department of Radiation Oncology, Hubei Cancer Hospital, 116 South Road, Zhuodaoquan, Wuhan 430079, China
| | - Shaozhong Wei
- Department of Gastrointestinal & Genitourinary Oncology, Hubei Cancer Hospital, 116 South Road, Zhuodaoquan, Wuhan 430079, China
| | - Desheng Hu
- Department of Radiation Oncology, Hubei Cancer Hospital, 116 South Road, Zhuodaoquan, Wuhan 430079, China
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Yu H, Caldwell C, Balogh J, Mah K. Toward magnetic resonance-only simulation: segmentation of bone in MR for radiation therapy verification of the head. Int J Radiat Oncol Biol Phys 2014; 89:649-57. [PMID: 24803040 DOI: 10.1016/j.ijrobp.2014.03.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 02/10/2014] [Accepted: 03/06/2014] [Indexed: 12/19/2022]
Abstract
PURPOSE To develop a practical method to localize bones in magnetic resonance (MR) images, to create "computed tomography-like" MR images (ctMRI) that could be used for radiation therapy verification, and to generate MR-based digitally reconstructed radiographs (DRR). METHODS AND MATERIALS Using T1-weighted MR images, an air mask was derived from the manual contouring of all airways within the head and neck region using axial images at 6 anatomic levels. Compact bone, spongy bone, and soft tissue masks were then automatically generated using the statistical data derived from MR intensities and the air mask. ctMRI were then generated by mapping the MR intensities of the voxels within these masks into the CT number ranges of corresponding tissues. MR-based DRRs created from ctMRI were quantitatively evaluated using the co-registered MR and CT head images of 20 stereotactic radiosurgery patients. Ten anatomical points, positioned on the skull segmented using a threshold of 300 HU, in CT and ctMRI, were used to determine the differences in distance between MR-based DRRs and CT-based DRRs, and to evaluate the geometric accuracy of ctMRI and MR-based DRRs. RESULTS The bony structures were identified on ctMRI and were visible in the MR-based DRRs. From the 20 patient cases, the mean geometric difference and standard deviation between the 10 anatomical points on MR-based and CT-based DRRs was -0.05 ± 0.85 mm, respectively. This included uncertainty in image fusion. The maximum distance difference was 1.88 mm. CONCLUSIONS A practical method was developed to segment bone from MR images. The ctMRI created can be used for radiation treatment verification when MR-only simulation is performed. MR-based DRRs can be used in place of CT-based DRRs.
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Affiliation(s)
- Huan Yu
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Science Center, Toronto, ON, Canada
| | - Curtis Caldwell
- Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada; Medical Imaging, Sunnybrook Health Science Center, Toronto, ON, Canada; Department of Medical Imaging, University of Toronto, Toronto, ON, Canada
| | - Judith Balogh
- Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Science Center, Toronto, ON, Canada; Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada
| | - Katherine Mah
- Department of Medical Physics, Odette Cancer Centre, Sunnybrook Health Science Center, Toronto, ON, Canada; Department of Radiation Oncology, University of Toronto, Toronto, ON, Canada.
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25
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Regini F, Gourtsoyianni S, Cardoso De Melo R, Charles-Edwards GD, Griffin N, Parikh J, Rottenberg G, Leslie M, Gaya A, Goh V. Rectal tumour volume (GTV) delineation using T2-weighted and diffusion-weighted MRI: Implications for radiotherapy planning. Eur J Radiol 2014; 83:768-72. [PMID: 24646719 DOI: 10.1016/j.ejrad.2014.02.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 02/03/2014] [Accepted: 02/05/2014] [Indexed: 01/09/2023]
Abstract
PURPOSE To compare the rectal tumour gross target volume (GTV) delineated on T2 weighted (T2W MRI) and diffusion weighted MRI (DWI) images by two different observers and to assess if agreement is improved by DWI. MATERIAL AND METHODS 27 consecutive patients (15 male, range 27.1-88.8 years, mean 66.9 years) underwent 1.5T MRI prior to chemoradiation (45Gy in 25 fractions; oral capecitabine 850mg/m(2)), including axial T2W MRI (TR=6600ms, TE=90ms) and DWI (TR=3000ms, TE=77ms, b=0, 100, 800s/mm(2)). 3D tumour volume (cm(3)) was measured by volume of interest (VOI) analysis by two independent readers for the T2W MRI and b800 DWI axial images, and the T2W MRI and DWI volumes compared using Mann-Whitney test. Observer agreement was assessed using Bland-Altman statistics. Significance was at 5%. RESULTS Artefacts precluded DWI analysis in 1 patient. In the remaining 26 patients evaluated, median (range) T2W MRI MRI and DWI (b=800s/mm(2)) 3D GTVin cm(3) were 33.97 (4.44-199.8) and 31.38 (2.43-228), respectively, for Reader One and 43.78 (7.57-267.7) and 42.45 (3.68-251) for Reader Two. T2W MRI GTVs were slightly larger but not statistically different from DWI volumes: p=0.52 Reader One; p=0.92 Reader Two. Interobserver mean difference (95% limits of agreement) for T2W MRI and DWI GTVs were -9.84 (-54.96 to +35.28) cm(3) and -14.79 (-54.01 to +24.43) cm(3) respectively. CONCLUSION Smaller DWI volumes may result from better tumour conspicuity but overall observer agreement is not improved by DWI.
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Affiliation(s)
- F Regini
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK; Department of Experimental and Clinical Biomedical Sciences - Radiodiagnostic Unit 2 - University of Florence- Azienda Ospedaliero-Universitaria Careggi, Firenze, Italy.
| | - S Gourtsoyianni
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK.
| | - R Cardoso De Melo
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK.
| | - G D Charles-Edwards
- Division of Imaging Sciences & Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK; Medical Physics, Guy's & St Thomas' NHS Foundation Trust, London, UK.
| | - N Griffin
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK.
| | - J Parikh
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK.
| | - G Rottenberg
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK.
| | - M Leslie
- Department of Clinical Oncology, Guy's & St Thomas' NHS Foundation Trust, London, UK.
| | - A Gaya
- Department of Clinical Oncology, Guy's & St Thomas' NHS Foundation Trust, London, UK.
| | - V Goh
- Department of Radiology,Guy's & St Thomas' NHS Foundation Trust, London, UK; Division of Imaging Sciences & Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, UK.
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26
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Hassan M, Chaudhry A, Khan A, Iftikhar MA. Robust information gain based fuzzy c-means clustering and classification of carotid artery ultrasound images. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2014; 113:593-609. [PMID: 24239296 DOI: 10.1016/j.cmpb.2013.10.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 09/26/2013] [Accepted: 10/15/2013] [Indexed: 06/02/2023]
Abstract
In this paper, a robust method is proposed for segmentation of medical images by exploiting the concept of information gain. Medical images contain inherent noise due to imaging equipment, operating environment and patient movement during image acquisition. A robust medical image segmentation technique is thus inevitable for accurate results in subsequent stages. The clustering technique proposed in this work updates fuzzy membership values and cluster centroids based on information gain computed from the local neighborhood of a pixel. The proposed approach is less sensitive to noise and produces homogeneous clustering. Experiments are performed on medical and non-medical images and results are compared with state of the art segmentation approaches. Analysis of visual and quantitative results verifies that the proposed approach outperforms other techniques both on noisy and noise free images. Furthermore, the proposed technique is used to segment a dataset of 300 real carotid artery ultrasound images. A decision system for plaque detection in the carotid artery is then proposed. Intima media thickness (IMT) is measured from the segmented images produced by the proposed approach. A feature vector based on IMT values is constructed for making decision about the presence of plaque in carotid artery using probabilistic neural network (PNN). The proposed decision system detects plaque in carotid artery images with high accuracy. Finally, effect of the proposed segmentation technique has also been investigated on classification of carotid artery ultrasound images.
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Affiliation(s)
- Mehdi Hassan
- Pattern Recognition Lab (DCIS), PIEAS, P.O. Nilore 45650, Islamabad, Pakistan
| | | | - Asifullah Khan
- Pattern Recognition Lab (DCIS), PIEAS, P.O. Nilore 45650, Islamabad, Pakistan.
| | - M Aksam Iftikhar
- Pattern Recognition Lab (DCIS), PIEAS, P.O. Nilore 45650, Islamabad, Pakistan
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27
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Organ-focused mutual information for nonrigid multimodal registration of liver CT and Gd–EOB–DTPA-enhanced MRI. Med Image Anal 2014; 18:22-35. [DOI: 10.1016/j.media.2013.09.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 08/07/2013] [Accepted: 09/05/2013] [Indexed: 11/23/2022]
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28
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Wang YY, Zhe H. Clinical application of multimodality imaging in radiotherapy treatment planning for rectal cancer. Cancer Imaging 2013; 13:495-501. [PMID: 24334539 PMCID: PMC3864219 DOI: 10.1102/1470-7330.2013.0046] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Radiotherapy plays an important role in the treatment of rectal cancer. Three-dimensional conformal radiotherapy and intensity-modulated radiotherapy are mainstay techniques of radiotherapy for rectal cancer. However, the success of these techniques is heavily reliant on accurate target delineation and treatment planning. Computed tomography simulation is a cornerstone of rectal cancer radiotherapy, but there are limitations, such as poor soft-tissue contrast between pelvic structures and partial volume effects. Magnetic resonance imaging and positron emission tomography (PET) can overcome these limitations and provide additional information for rectal cancer treatment planning. PET can also reduce the interobserver variation in the definition of rectal tumor volume. However, there is a long way to go before these image modalities are routinely used in the clinical setting. This review summarizes the most promising studies on clinical applications of multimodality imaging in target delineation and treatment planning for rectal cancer radiotherapy.
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Affiliation(s)
- Yan Yang Wang
- Department of Radiation Oncology, General Hospital of Ningxia Medical University, Yinchuan, China
| | - Hong Zhe
- Department of Radiation Oncology, General Hospital of Ningxia Medical University, Yinchuan, China
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Abstract
Over the last two decades, the computed tomography simulator became the standard of the contemporary radiotherapy treatment planning (RTP) process. Along the same time, the superb soft tissue contrast of magnetic resonance imaging (MRI) was widely incorporated into RTP through the process of image coregistration. This review summarizes the efforts of incorporation of MRI data into target definition process for RTP based on gained clinical evidence so far and opens a question whether the time is up for bringing a MRI-simulator as an additional standard imaging tool into radiation oncology departments.
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Affiliation(s)
- Slobodan Devic
- Department of Radiation Oncology, Jewish General Hospital, McGill University, Montréal, Québec, Canada.
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30
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Gwynne S, Webster R, Adams R, Mukherjee S, Coles B, Staffurth J. Image-guided Radiotherapy for Rectal Cancer — A Systematic Review. Clin Oncol (R Coll Radiol) 2012; 24:250-60. [DOI: 10.1016/j.clon.2011.07.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 06/16/2011] [Accepted: 07/04/2011] [Indexed: 11/27/2022]
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31
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Gwynne S, Mukherjee S, Webster R, Spezi E, Staffurth J, Coles B, Adams R. Imaging for target volume delineation in rectal cancer radiotherapy--a systematic review. Clin Oncol (R Coll Radiol) 2011; 24:52-63. [PMID: 22035634 DOI: 10.1016/j.clon.2011.10.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Revised: 09/15/2011] [Accepted: 09/19/2011] [Indexed: 01/09/2023]
Abstract
The global move towards more conformal radiotherapy for rectal cancer requires better imaging modalities that both visualise the disease accurately and are reproducible; to reduce interobserver variation. This review explores the advances in imaging modalities used in target volume delineation, with a view to make recommendations for current clinical practice and to propose future directions for research. A systematic review was conducted using MEDLINE and EMBASE. Articles considered relevant by the authors were included. Planning with orthogonal films is being replaced by computed tomography (CT) simulation. This is now considered the 'gold standard' and allows conformal three-dimensional planning. Magnetic resonance imaging (MRI) has been shown to overcome some of the limitations of CT and can be used either as a diagnostic image to visually aid planning, or as a 'planning' MRI carried out in the treatment position and co-registered with the planning CT. The latter approach has been shown to change the treated volumes compared with CT and in prostate cancer patients has been shown to reduce interobserver variation. There are remaining issues with four-dimensional motion that are yet to be fully appreciated or overcome. 2-[18F] fluoro-2-deoxy-d-glucose positron emission tomography/CT co-registered with planning CT results in smaller volumes than CT alone and also reduces interobserver variation, but requires further validation before routine implementation. Experimental work utilising novel positron emission tomography tracers and diffusion-weighted MRI shows promise and requires further evaluation. Rigorous quality assurance is important with processing of newer imaging modalities. Further work needs to be conducted into both interobserver variation and the formal evaluation of the clinical benefits of newer imaging modalities. Developments in image-guided radiotherapy are also required to ensure that improvements in target definition at the planning stage are reproducible throughout treatment.
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Affiliation(s)
- S Gwynne
- Department of Clinical Oncology, Velindre Cancer Centre, Cardiff, UK.
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