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Matsutomo N, Seki H, Hishikawa M, Motegi K, Yamamoto T. Technical Note: Development of an ischemic defect model insert attachable to a commercially available myocardial phantom. Med Phys 2020; 47:4340-4347. [PMID: 32463928 DOI: 10.1002/mp.14296] [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: 02/11/2020] [Revised: 05/14/2020] [Accepted: 05/19/2020] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVE The purpose of this study was to develop a novel myocardial phantom insert model that attaches to commercially available myocardial phantoms and simulates an ischemic area, using three-dimensional printing technology. METHODS Ischemic inserts were designed to give four levels of absolute percent contrast (Low; 10%, Medium; 20%, High; 35%, and Defect; 100%) using CT images and computer-aided design software. The ischemic insert was composed of multiple slit structures to replicate myocardial ischemia. Myocardial phantom images with developed ischemic inserts were acquired using a SPECT/CT system and were then reconstructed using filtered back projection (FBP) and iterative reconstruction (IR) with various cutoff frequencies of a Butterworth filter. The performance and utility of ischemic inserts were evaluated according to percent contrast and 5-point scoring. RESULTS The percent contrast and scoring results changed according to the ischemic insert type, cutoff frequency, and reconstruction method. The percent contrast of each insert obtained by FBP with 0.4 cycles/cm was 4.1% (Low), 15.7% (Medium), 17.4% (High), and 36.1% (Defect). Similarly, the percent contrast of each insert obtained by IR with 0.4 cycles/cm was 5.0% (Low), 17.0% (Medium), 21.9% (High), and 47.7% (Defect). CONCLUSIONS We successfully developed an ischemic insert that attaches to a commercially available myocardial phantom by using CT imaging and 3D printing technology. Our proposed ischemic insert provided several abnormal perfusion patterns on myocardial SPECT images and may be useful for evaluating SPECT image quality.
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Affiliation(s)
- Norikazu Matsutomo
- Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan.,Graduate School of Health Sciences, Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan
| | - Harumi Seki
- Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan
| | - Mizuho Hishikawa
- Graduate School of Health Sciences, Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan
| | - Kazuki Motegi
- Graduate School of Health Sciences, Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan.,Department of Nuclear Medicine, Cancer Institute Hospital, Japanese Foundation for Cancer Research, 3-8-31, Ariake, Koto, Tokyo, 135-8550, Japan
| | - Tomoaki Yamamoto
- Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan.,Graduate School of Health Sciences, Department of Medical Radiological Technology, Faculty of Health Sciences, Kyorin University, B-307, 5-4-1 Shimorenjaku Mitaka-shi, Tokyo, 181-8612, Japan
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Development of a myocardial phantom and analysis system toward the standardization of myocardial SPECT image across institutions. Ann Nucl Med 2016; 30:699-707. [PMID: 27544378 DOI: 10.1007/s12149-016-1113-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE We developed a novel myocardial phantom and analysis program to standardize using a quantitative index to objectively evaluate the image quality. We aimed to reveal whether our proposed phantom and analysis program are suitable for image standardization. METHODS An evaluation system of myocardial image based on technical grounds (EMIT) phantom was developed to standardize the image quality of myocardial SPECT and was constructed with the lung and myocardium in the thorax phantom; the myocardial phantom included five normal areas and eight defective areas with four defects in size (5, 10, 15, and 20 mm) and four defects in thickness (10, 7.5, 5, and 2.5 mm). Therefore, this phantom was appropriate to simultaneously simulate eight different defects and normal myocardium. The %rate value, calculated using the region of interest method, and the %count value, calculated from the profile method, were automatically analyzed to evaluate myocardial defects. The phantom was validated using difference in count levels and filter parameters compared with those in previously reported models. RESULTS The average %count of eight defects by 0.3, 0.4, 0.5, and 0.6 cycles/cm were 56.8, 47.4, 44.3, and 43.4 %, respectively, whereas the %count for 0.3 cycles/cm was significantly higher than that for 0.5 and 0.6 cycles/cm. The uniformity between full- and half-time images was 16.5 ± 4.2 and 18.7 ± 5.5 % for integral uniformity and 3.4 ± 1.2 and 3.4 ± 1.3 % for differential uniformity, respectively, revealing a significant difference in integral uniformity between the two acquisition times. Visual differences in defects were evident in full-time images between 0.30 and 0.50 cycles/cm, and defect detectability of the myocardial image at 0.30 cycles/cm was poor. Normal myocardial thickness widened in comparison with images at 0.50 cycles/cm. Compared with full-time myocardial image at the same cut-off frequency, the half-time myocardial image demonstrated inhomogeneous distribution and thickness of the normal myocardium. CONCLUSION We developed a new phantom and program to standard image quality among multicenter for myocardial SPECT. The EMIT phantom and quantitative indices were useful for evaluating image quality. The physical characteristics of the image quality, including defects and uniformity, were properly measured by this method.
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Trägårdh E, Ljungberg M, Edenbrandt L, Örndahl E, Johansson L, Gustafsson A, Jonsson C, Hagerman J, Riklund K, Minarik D. Evaluation of inter-departmental variability of ejection fraction and cardiac volumes in myocardial perfusion scintigraphy using simulated data. EJNMMI Phys 2015; 2:2. [PMID: 26501804 PMCID: PMC4545220 DOI: 10.1186/s40658-014-0105-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 12/09/2014] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Myocardial perfusion scintigraphy (MPS) is a clinically useful noninvasive imaging modality for diagnosing patients with suspected coronary artery disease. By utilizing gated MPS, the end diastolic volume (EDV) and end systolic volume (ESV) can be measured and the ejection fraction (EF) calculated, which gives incremental prognostic value compared with assessment of perfusion only. The aim of this study was to evaluate the inter-departmental variability of EF, ESV, and EDV during gated MPS in Sweden. METHODS Seventeen departments were included in the study. The SIMIND Monte Carlo (MC) program together with the XCAT phantom was used to simulate three patient cases with different EDV, ESV, and EF. Individual simulations were performed for each department, corresponding to their specific method of performing MPS. Images were then sent to each department and were evaluated according to clinical routine. EDV, ESV, and EF were reported back. RESULTS There was a large underestimation of EDV and ESV for all three cases. Mean underestimation for EDV varied between 26% and 52% and for ESV between 15% and 60%. EF was more accurately measured, but mean bias still varied between an underestimation of 24% to an overestimation of 14%. In general, the intra-departmental variability for EDV, ESV, and EF was small, whereas inter-departmental variability was larger. CONCLUSIONS Left ventricular volumes were generally underestimated, whereas EF was more accurately estimated. There was, however, large inter-departmental variability.
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Affiliation(s)
- Elin Trägårdh
- Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Lund University Hospital, Inga Marie Nilssons gata 49, 205 02, Malmö, Sweden.
| | - Michael Ljungberg
- Department of Medical Radiation Physics, Lund University, Lund, Sweden.
| | - Lars Edenbrandt
- Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Lund University Hospital, Inga Marie Nilssons gata 49, 205 02, Malmö, Sweden.
| | | | - Lena Johansson
- Clinical Physiology, Central Hospital, Karlstad, Sweden.
| | - Agneta Gustafsson
- Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
| | - Cathrine Jonsson
- Department of Medical Physics, Karolinska University Hospital, Stockholm, Sweden.
| | - Jessica Hagerman
- Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Lund University Hospital, Inga Marie Nilssons gata 49, 205 02, Malmö, Sweden.
| | - Katrine Riklund
- Department of Radiation Sciences, Umeå University, Umeå, Sweden.
| | - David Minarik
- Radiation Physics, Skåne University Hospital, Lund University, Malmö, Sweden.
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Hovland A, Staub UH, Bjørnstad H, Prytz J, Sexton J, Støylen A, Vik-Mo H. Gated SPECT offers improved interobserver agreement compared with echocardiography. Clin Nucl Med 2011; 35:927-30. [PMID: 21206222 DOI: 10.1097/rlu.0b013e3181f9ddfb] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE Left ventricular ejection fraction (EF) is a powerful predictor of prognosis in coronary artery disease. The purpose of the present study was to measure interobserver differences for gated SPECT (GSPECT) software and echocardiography, and to compare these modalities regarding left ventricular volumes and EF. MATERIALS AND METHODS Eighty-four patients scheduled for nuclear imaging underwent a 1-day GSPECT with Tc-99m-tetrofosmin. Images were processed by 2 raters who calculated volumes and EF using Cedar-Sinai quantitative gated-SPECT (QGS), Emory Cardiac Toolbox (ECT), and 4D-MSPECT of the University of Michigan. Echocardiographic volumes were measured by 2 raters. Interobserver reliability was assessed by intraclass correlation coefficient (ICC). Differences in volumes and EF between echocardiography and GSPECT were compared with t-tests. RESULTS ICC was 0.61 for echocardiography, 0.94 for QGS, 0.88 for ECT, and 0.91 for 4D-MSPECT (P < 0.0001 compared with echocardiography). For small ventricles (ESV ≤30 mL), ICC was 0.58 for echocardiography and 0.90 for QGS (P = 0.008 compared with echocardiography); 0.77 and 0.73 for ECT and 4D-MSPECT, respectively (P = ns). End-diastolic and end-systolic volumes were significantly larger with GSPECT than with echocardiography, also echocardiographic ejection fraction was significantly different from GSPECT. CONCLUSIONS There is better interobserver reliability in GSPECT as compared with echocardiography, and QGS seems more robust in this study especially when it comes to small ventricles.
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Affiliation(s)
- Anders Hovland
- Coronary Care Unit, Department of Internal Medicine, Nordland Hospital, Bodø, Norway.
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America YGCJ, Bax JJ, Boersma E, Stokkel M, van der Wall EE. The additive prognostic value of perfusion and functional data assessed by quantitative gated SPECT in women. J Nucl Cardiol 2009; 16:10-9. [PMID: 19152124 DOI: 10.1007/s12350-008-9012-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2008] [Revised: 07/15/2008] [Accepted: 07/31/2008] [Indexed: 11/26/2022]
Abstract
BACKGROUND The aim of this study was to assess the prognostic value of technetium-99m tetrofosmin gated SPECT imaging in women using quantitative gated single photon emission computed tomography (SPECT) imaging. METHODS We followed 453 consecutive female patients. Average follow-up was 1.33 years (max. 2.55). Hard endpoints were cardiac death, acute myocardial infarction, or documented ventricular fibrillation. Event-free survival curves were obtained. Optimal cutoff values for left ventricular (LV) volumes, LV ejection fraction (LVEF), and perfusion data to predict outcome were determined by ROC curve analysis. RESULTS A total of 236 patients had an abnormal study, of whom 27 patients experienced hard events (16 deaths) and 47 patients soft events. For hard events summed stress score (SSS) and LVEF, and for any cardiac event SSS showed independent incremental prognostic value. The survival curves were maximally separated when using cutoff values for SSS of > or = 22 and LVEF < 52% (P < 0.001, HR 4.61 and P < 0.001 HR 5.24 for SSS and LVEF resp.), and SSS > or = 14 (P < 0.001 HR 3.76) for any cardiac event. CONCLUSION In women, perfusion and functional parameters derived from quantitative gated technetium-99m tetrofosmin SPECT imaging can adequately be used for cardiac risk assessment. Using quantitative gated SPECT, female patients with an LVEF < 52% or an SSS > or = 22 are at increased risk for subsequent hard events. Furthermore, patients with an SSS > or = 14 are at increased risk for any cardiac events.
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Affiliation(s)
- Yves G C J America
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC, Leiden, The Netherlands
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Ye Y, Bogaert J. Cell therapy in myocardial infarction: emphasis on the role of MRI. Eur Radiol 2007; 18:548-69. [DOI: 10.1007/s00330-007-0777-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2007] [Revised: 08/31/2007] [Accepted: 09/04/2007] [Indexed: 01/14/2023]
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