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Cerić Andelius I, Fridriksdóttir R, Minarik D, Hedeer F, Stenvall A, Trägårdh E, Oddstig J. Verification of reprojected planar images generated from a ring-configured cadmium zinc telluride gamma camera in scintigraphy for diagnosing transthyretin cardiac amyloidosis. EUROPEAN HEART JOURNAL. IMAGING METHODS AND PRACTICE 2024; 2:qyae051. [PMID: 39224107 PMCID: PMC11367964 DOI: 10.1093/ehjimp/qyae051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Accepted: 05/23/2024] [Indexed: 09/04/2024]
Abstract
Aims Non-invasive diagnosis of amyloid transthyretin (ATTR) cardiac amyloidosis using planar scintigraphy and single-photon emission computed tomography-computed tomography (SPECT-CT) with [99mTc]Tc-3,3-diphosphono-1,2-propanodicarboxylic acid ([99mTc]Tc-DPD) has high specificity and sensitivity. However, the introduction of ring-configured cadmium zinc telluride (CZT) gamma cameras warrants an update in the acquisition method since these systems are not able to perform planar scintigraphy. We aimed to verify the use of reprojected planar images from SPECT-CT as a replacement for planar scintigraphy in evaluating ATTR-amyloidosis. Methods and results The study examined 30 patients referred for clinically indicated [99mTc]Tc-DPD scintigraphy who were scanned with both a conventional gamma camera and a ring-configured CZT gamma camera. Planar scintigraphy from the conventional gamma camera was compared with reprojected planar images from the ring-configured CZT gamma camera. The images were evaluated in regard to image quality and Perugini visual score in a blinded fashion by three nuclear medicine physicians. Heart-to-contralateral (H/CL) ratios were calculated. There were 27 patients who had an identical Perugini score in planar and reprojected planar images, yielding a strong level of agreement and inter-rater reliability among the three readers. The H/CL ratios showed a strong correlation ratio (r = 0.98, P < 0.0001). A shift towards lower image quality was seen for the reprojected images. Conclusion Reprojected planar images generated from a ring-configured CZT gamma camera combined with SPECT-CT can be used to score ATTR amyloidosis and extract H/CL ratios in the same way as planar images and SPECT-CT from a conventional gamma camera.
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Affiliation(s)
- Irma Cerić Andelius
- Radiation Physics, Department of Haematology, Oncology and Radiation Physicis, Skåne University Hospital, 221 85 Lund, Sweden
- Department of Translational Medicine and Wallenberg Centre of Molecular Medicine, Lund University, Carl Bertil Laurells gata 9, 205 02 Malmö, Sweden
| | - Ragnheidur Fridriksdóttir
- Department of Translational Medicine and Wallenberg Centre of Molecular Medicine, Lund University, Carl Bertil Laurells gata 9, 205 02 Malmö, Sweden
- Department of Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Entrégatan 7, 221 85 Lund/Inga Marie Nilssons gata 47, 205 02 Malmö, Sweden
| | - David Minarik
- Radiation Physics, Department of Haematology, Oncology and Radiation Physicis, Skåne University Hospital, 221 85 Lund, Sweden
- Department of Translational Medicine and Wallenberg Centre of Molecular Medicine, Lund University, Carl Bertil Laurells gata 9, 205 02 Malmö, Sweden
| | - Fredrik Hedeer
- Department of Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Entrégatan 7, 221 85 Lund/Inga Marie Nilssons gata 47, 205 02 Malmö, Sweden
- Department of Clinical Sciences, Lund University, Sölvegatan 19, 221 84 Lund, Sweden
| | - Anna Stenvall
- Radiation Physics, Department of Haematology, Oncology and Radiation Physicis, Skåne University Hospital, 221 85 Lund, Sweden
| | - Elin Trägårdh
- Department of Translational Medicine and Wallenberg Centre of Molecular Medicine, Lund University, Carl Bertil Laurells gata 9, 205 02 Malmö, Sweden
- Department of Clinical Physiology and Nuclear Medicine, Skåne University Hospital, Entrégatan 7, 221 85 Lund/Inga Marie Nilssons gata 47, 205 02 Malmö, Sweden
| | - Jenny Oddstig
- Radiation Physics, Department of Haematology, Oncology and Radiation Physicis, Skåne University Hospital, 221 85 Lund, Sweden
- Department of Translational Medicine and Wallenberg Centre of Molecular Medicine, Lund University, Carl Bertil Laurells gata 9, 205 02 Malmö, Sweden
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Nakajima K, Shibutani T. Are nuclear medicine images quantified in 2D and 3D equally functional? J Nucl Cardiol 2023; 30:1968-1972. [PMID: 37156963 DOI: 10.1007/s12350-023-03290-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Accepted: 04/12/2023] [Indexed: 05/10/2023]
Affiliation(s)
- Kenichi Nakajima
- Department of Functional Imaging and Artificial Intelligence, Kanazawa University, 13-1 Takara-Machi, Kanazawa, 920-8640, Japan.
| | - Takayuki Shibutani
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
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Verrecchia-Ramos E, Morel O, Ginet M, Retif P, Ben Mahmoud S. Clinical validation of an AI-based automatic quantification tool for lung lobes in SPECT/CT. EJNMMI Phys 2023; 10:57. [PMID: 37733103 PMCID: PMC10513978 DOI: 10.1186/s40658-023-00578-z] [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: 12/05/2022] [Accepted: 09/05/2023] [Indexed: 09/22/2023] Open
Abstract
BACKGROUND Lung lobar ventilation and perfusion (V/Q) quantification is generally obtained by generating planar scintigraphy images and then imposing three equally sized regions of interest on the data of each lung. This method is fast but not as accurate as SPECT/CT imaging, which provides three-dimensional data and therefore allows more precise lobar quantification. However, the manual delineation of each lobe is time-consuming, which makes SPECT/CT incompatible with the clinical workflow for V/Q estimation. An alternative may be to use artificial intelligence-based auto-segmentation tools such as AutoLung3D (Siemens Healthineers, Knoxville, USA), which automatically delineate the lung lobes on the CT data acquired with the SPECT data. The present study assessed the clinical validity of this approach relative to planar scintigraphy and manual quantification in SPECT/CT. METHODS The Autolung3D software was tested on the retrospective SPECT/CT data of 43 patients who underwent V/Q scintigraphy with 99mTc-macroaggregated albumin and 99mTc-labeled aerosol. It was compared to planar scintigraphy and SPECT/CT using the manual quantification method in terms of relative lobar V/Q quantification values and interobserver variability. RESULTS The three methods provided similar V/Q estimates for the left lung lobes and total lungs. However, compared to the manual SPECT/CT method, planar scintigraphy yielded significantly higher estimates for the middle right lobe and significantly lower estimates for the superior and inferior right lobes. The estimates of the manual and automated SPECT/CT methods were similar. However, the post-processing time in the automated method was approximately 5 min compared to 2 h for the manual method. Moreover, the automated method associated with a drastic reduction in interobserver variability: Its maximal relative standard deviation was only 5%, compared to 23% for planar scintigraphy and 19% for the manual SPECT/CT method. CONCLUSIONS This study validated the AutoLung3D software for general clinical use since it rapidly provides accurate lobar quantification in V/Q scans with markedly less interobserver variability than planar scintigraphy or the manual SPECT/CT method.
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Affiliation(s)
- Emilie Verrecchia-Ramos
- Department of Medical Physics, Mercy Hospital, CHR Metz-Thionville, 1, Allée du Château, 57530, Ars-Laquenexy, France.
| | - Olivier Morel
- Department of Nuclear Medicine, Mercy Hospital, CHR Metz-Thionville, 1, Allée du Château, 57530, Ars-Laquenexy, France
| | - Merwan Ginet
- Department of Nuclear Medicine, Mercy Hospital, CHR Metz-Thionville, 1, Allée du Château, 57530, Ars-Laquenexy, France
| | - Paul Retif
- Department of Medical Physics, Mercy Hospital, CHR Metz-Thionville, 1, Allée du Château, 57530, Ars-Laquenexy, France
- CNRS, CRAN, Université de Lorraine, 54000, Nancy, France
| | - Sinan Ben Mahmoud
- Department of Nuclear Medicine, Mercy Hospital, CHR Metz-Thionville, 1, Allée du Château, 57530, Ars-Laquenexy, France
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Alqahtani M, Willowson K, Fulton R, Constable C, Kench P. Transition to Fast Whole-Body SPECT/CT Bone Imaging: An Assessment of Image Quality. Diagnostics (Basel) 2022; 12:2938. [PMID: 36552946 PMCID: PMC9776819 DOI: 10.3390/diagnostics12122938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 11/20/2022] [Accepted: 11/20/2022] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To investigate the impact of reduced SPECT acquisition time on reconstructed image quality for diagnostic purposes. METHOD Data from five patients referred for a routine bone SPECT/CT using the standard multi-bed SPECT/CT protocol were reviewed. The acquisition time was 900 s using gating technique; SPECT date was resampled into reduced data sets of 480 s, 450 s, 360 s and 180 s acquisition duration per bed position. Each acquisition time was reconstructed using a fixed number of subsets (8 subsets) and 4, 8, 12, and 16 iterations, followed by a post-reconstruction 3D Gaussian filter of 8 mm FWHM. Two Nuclear Medicine physicians analysed all images independently to score image quality, noise and diagnostic confidence based on a pre-defined 4-point scale. RESULTS Our result showed that the most frequently selected categories for 480 s and 450 s images were good image quality, average noise and fair confidence, particularly at lower iteration numbers 4 and 8. For the shortened acquisition time of 360 s and 180 s, statistical significance was observed in most reconstructed images compared with 900 s. CONCLUSION The SPECT/CT can significantly shorten the acquisition time with maintained image quality, noise and diagnostic confidence. Therefore, acquiring data over 480 s and 450 s is feasible for WB-SPECT/CT bone scans to provide an optimal balance between acquisition time and image quality.
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Affiliation(s)
- Mansour Alqahtani
- Discipline of Medical Imaging Science, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- Department of Radiology and Medical Imaging, Faculty of Applied Medical Sciences, Najran University, Najran 61441, Saudi Arabia
| | - Kathy Willowson
- Department of Nuclear Medicine, Royal North Shore Hospital, St Leonards, NSW 2065, Australia
- Institute of Medical Physics, Faculty of Science, The University of Sydney, Sydney, NSW 2006, Australia
| | - Roger Fulton
- Discipline of Medical Imaging Science, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
- Department of Medical Physics, Westmead Hospital, Sydney, NSW 2145, Australia
| | - Chris Constable
- HERMES Medical Solutions, Strandbergsgatan 16, 112 51 Stockholm, Sweden
| | - Peter Kench
- Discipline of Medical Imaging Science, Faculty of Medicine and Health, The University of Sydney, Camperdown, NSW 2006, Australia
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Comparison of reprojected bone SPECT/CT and planar bone scintigraphy for the detection of bone metastases in breast and prostate cancer. Nucl Med Commun 2022; 43:510-517. [PMID: 35081092 DOI: 10.1097/mnm.0000000000001536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The aim of this study was to compare reprojected bone SPECT/CT (RBS) against planar bone scintigraphy (BS) in the detection of bone metastases in breast and prostate cancer patients. METHODS Twenty-six breast and 105 prostate cancer patients with high risk for bone metastases underwent 99mTc-HMDP BS and whole-body SPECT/CT, 1.5-T whole-body diffusion-weighted MRI and 18F-NaF or 18F-PSMA-1007 PET/CT within two prospective clinical trials (NCT01339780 and NCT03537391). Consensus reading of all imaging modalities and follow-up data were used to define the reference standard diagnosis. The SPECT/CT data were reprojected into anterior and posterior views to produce RBS images. Both BS and RBS images were independently double read by two pairs of experienced nuclear medicine physicians. The findings were validated against the reference standard diagnosis and compared between BS and RBS on the patient, region and lesion levels. RESULTS All metastatic patients detected by BS were also detected by RBS. In addition, three metastatic patients were missed by BS but detected by RBS. The average patient-level sensitivity of two readers for metastases was 75% for BS and 87% for RBS, and the corresponding specificity was 79% for BS and 39% for RBS. The average region-level sensitivity of two readers was 64% for BS and 69% for RBS, and the corresponding specificity was 96% for BS and 87% for RBS. CONCLUSION Whole-body bone SPECT/CT can be reprojected into more familiar anterior and posterior planar images with excellent sensitivity for bone metastases, making additional acquisition of planar BS unnecessary.
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Bailey DL, Roach PJ. A Brief History of Lung Ventilation and Perfusion Imaging Over the 50-Year Tenure of the Editors of Seminars in Nuclear Medicine. Semin Nucl Med 2019; 50:75-86. [PMID: 31843063 DOI: 10.1053/j.semnuclmed.2019.07.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The ventilation/perfusion lung scan has been in continuous use for approximately half a century, the same lifetime as Seminars in Nuclear Medicine. Remarkably, the founding Editors-in-Chief have continued to guide the journal over this entire period. In this Feschrift issue celebrating their enormous contribution, we review the history of the lung scan, its highs and lows, the transition from planar to SPECT/CT V/Q scans, and the future that is in store in this age of multimodality functional imaging. We concur with the published view of one of the retiring editors (LMF) that V/Q scintigraphy is indeed alive and well and has a definite future in clinical medicine.
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Affiliation(s)
- Dale L Bailey
- Royal North Shore Hospital, Department of Nuclear Medicine, Sydney, Australia; University of Sydney, Faculty of Medicine & Health, Sydney, Australia.
| | - Paul J Roach
- Royal North Shore Hospital, Department of Nuclear Medicine, Sydney, Australia; University of Sydney, Faculty of Medicine & Health, Sydney, Australia
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Bailey DL. Thirty years from now: future physics contributions in nuclear medicine. EJNMMI Phys 2014; 1:4. [PMID: 26501446 PMCID: PMC4545811 DOI: 10.1186/2197-7364-1-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 02/28/2014] [Indexed: 12/04/2022] Open
Abstract
Background This paper is the first in a series of invited perspectives by pioneers of nuclear medicine imaging and physics. A medical physicist and a nuclear medicine physician each take a backward and a forward look at the contributions of physics to nuclear medicine. Here, we provide a forward look from the medical physicist’s perspective. Discussion The author examines a number of developments in nuclear medicine and discusses the ways in which physics has contributed to these. Future developments are postulated in the context of an increasingly personalised approach to medical diagnostics and therapies. Conclusions A skill set for the next generation of medical physicists in nuclear medicine is proposed in the context of the increasing complexity of ‘Molecular Imaging’ in the next three decades. The author sees a shift away from ‘traditional’ roles in instrumentation QA to more innovative approaches in understanding radiobiology and human disease.
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Affiliation(s)
- Dale L Bailey
- School of Physics and Faculty of Health Sciences, University of Sydney, Sydney, 2006, Australia. .,Department of Nuclear Medicine, Royal North Shore Hospital, St. Leonards, NSW, 2065, Australia.
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Abstract
Planar ventilation-perfusion (V/Q) scanning is often used to investigate pulmonary embolism; however, it has well-recognized limitations. SPECT overcomes many of these through its ability to generate 3-dimensional imaging data. V/Q SPECT has higher sensitivity, specificity, and accuracy than planar imaging and a lower indeterminate rate. SPECT allows for new ways to display and analyze data, such as parametric V/Q ratio images. Compared with CT pulmonary angiography, SPECT has higher sensitivity, a lower radiation dose, fewer technically suboptimal studies, and no contrast-related complications. Any nuclear medicine department equipped with a modern hybrid scanner can now perform combined V/Q SPECT with CT (using low-dose protocols) to further enhance diagnostic accuracy. V/Q SPECT (with or without CT) has application in other pulmonary conditions and in research.
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Affiliation(s)
- Paul J Roach
- Department of Nuclear Medicine, Royal North Shore Hospital, and Sydney Medical School, University of Sydney, Sydney, Australia.
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Jha AK, Clarkson E, Kupinski MA, Barrett HH. Joint reconstruction of activity and attenuation map using LM SPECT emission data. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2013; 8668. [PMID: 26236067 DOI: 10.1117/12.2008111] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Attenuation and scatter correction in single photon emission computed tomography (SPECT) imaging often requires a computed tomography (CT) scan to compute the attenuation map of the patient. This results in increased radiation dose for the patient, and also has other disadvantages such as increased costs and hardware complexity. Attenuation in SPECT is a direct consequence of Compton scattering, and therefore, if the scattered photon data can give information about the attenuation map, then the CT scan may not be required. In this paper, we investigate the possibility of joint reconstruction of the activity and attenuation map using list-mode (LM) SPECT emission data, including the scattered-photon data. We propose a path-based formalism to process scattered-photon data. Following this, we derive analytic expressions to compute the Cramér-Rao bound (CRB) of the activity and attenuation map estimates, using which, we can explore the fundamental limit of information-retrieval capacity from LM SPECT emission data. We then suggest a maximum-likelihood (ML) scheme that uses the LM emission data to jointly reconstruct the activity and attenuation map. We also propose an expectation-maximization (EM) algorithm to compute the ML solution.
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Affiliation(s)
- Abhinav K Jha
- College of Optical Sciences, University of Arizona, Tucson, AZ, USA
| | - Eric Clarkson
- College of Optical Sciences, University of Arizona, Tucson, AZ, USA ; Department of Medical Imaging, University of Arizona, Tucson, AZ, USA
| | - Matthew A Kupinski
- College of Optical Sciences, University of Arizona, Tucson, AZ, USA ; Department of Medical Imaging, University of Arizona, Tucson, AZ, USA
| | - Harrison H Barrett
- College of Optical Sciences, University of Arizona, Tucson, AZ, USA ; Department of Medical Imaging, University of Arizona, Tucson, AZ, USA
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Planar images reprojected from SPECT V/Q data perform similarly to traditional planar V/Q scans in the diagnosis of pulmonary embolism. Nucl Med Commun 2013; 34:445-50. [PMID: 23442545 DOI: 10.1097/mnm.0b013e32835fa531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To compare the diagnostic interpretation of traditional ventilation/perfusion (V/Q) planar images with that of planar-like images reprojected from single-photon emission computed tomography (SPECT) data sets. METHODS Retrospective data from patients who had undergone both planar and SPECT imaging were used to generate anonymized reprojected planar images, which were compared with traditional planar V/Q images. Two consultants interpreted both sets of images for 81 patients following a proforma. We assessed the agreement in the final diagnosis between the two imaging methods and between the two clinicians. We also compared the number, nature, and localization of defects, as well as image quality. Finally, we compared the diagnosis made using planar methods with the original diagnosis made using SPECT. RESULTS There was excellent agreement in diagnosis both between the two planar methods (κ=0.93) and between the two consultants (κ=0.91). Similar numbers of defects were detected, with fewer matched defects being reported in the reprojected group by one of the clinicians. Localization of defects and image quality were similar for the two imaging methods. Six additional pulmonary embolisms were diagnosed using SPECT data. CONCLUSION We have shown that the performance of reprojected planars from SPECT V/Q was similar to that of traditional planars. These results have potential important implications for patient workflow in busy nuclear medicine departments, as well as for patient comfort.
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Freeman LM, Glaser JE, Haramati LB. Planar Ventilation-Perfusion Imaging for Pulmonary Embolism: The Case for “Outcomes” Medicine. Semin Nucl Med 2012; 42:3-10. [DOI: 10.1053/j.semnuclmed.2011.07.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Hutton BF, Buvat I, Beekman FJ. Review and current status of SPECT scatter correction. Phys Med Biol 2011; 56:R85-112. [PMID: 21701055 DOI: 10.1088/0031-9155/56/14/r01] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Roach PJ, Bailey DL, Schembri GP, Thomas PA. Transition from Planar to SPECT V/Q Scintigraphy: Rationale, Practicalities, and Challenges. Semin Nucl Med 2010; 40:397-407. [DOI: 10.1053/j.semnuclmed.2010.07.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Stein PD, Freeman LM, Sostman HD, Goodman LR, Woodard PK, Naidich DP, Gottschalk A, Bailey DL, Matta F, Yaekoub AY, Hales CA, Hull RD, Leeper KV, Tapson VF, Weg JG. SPECT in Acute Pulmonary Embolism. J Nucl Med 2009; 50:1999-2007. [DOI: 10.2967/jnumed.109.063958] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Attenuation correction for lung SPECT: evidence of need and validation of an attenuation map derived from the emission data. Eur J Nucl Med Mol Imaging 2009; 36:1076-89. [PMID: 19238381 DOI: 10.1007/s00259-009-1090-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2008] [Accepted: 01/30/2009] [Indexed: 10/21/2022]
Abstract
PURPOSE The aim of our study was to investigate the importance of attenuation correction (AC) in reconstructed and reprojected images on lung SPECT studies. METHODS Simulation studies were undertaken to evaluate the influence of AC on defect-to-normal ratios (D/N), to demonstrate the influence of errors in the correction map values and to detect lung boundaries used for AC. The use of a synthetic map (SM) for AC of the clinical data was also evaluated and the results compared with those obtained with data derived from CT (CTM). Additionally, the role of AC in reprojected SPECT data was assessed and level of noise on the 'planar-like' images was measured. RESULTS Phantom studies showed that AC markedly affects the D/N ratio. However, variations in micro values typical of those found in clinical studies resulted in relatively small changes in results. Eroded and dilated conditions did not cause any significant effect on D/N. The level of noise in the reprojected images is reduced in comparison with real planar data. Clinical SPECT/CT data reconstructed with AC using CTM and SM showed an excellent correlation between the two methods. CONCLUSION AC improves D/N in lung SPECT studies, thus potentially enhancing the diagnostic capability of the method. The use of a synthetic map for AC is feasible, avoiding the need for an additional procedure and the increased radiation dose involved. Planar-like images generated from reprojected SPECT data are well matched to normal planar images provided AC is performed and attenuation included in the reprojection.
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Roach PJ, Bailey DL, Schembri GP. Reinventing ventilation/perfusion lung scanning with SPECT. Nucl Med Commun 2008; 29:1023-5. [DOI: 10.1097/mnm.0b013e328315efa1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Roach PJ, Bailey DL, Harris BE. Enhancing Lung Scintigraphy With Single-Photon Emission Computed Tomography. Semin Nucl Med 2008; 38:441-9. [DOI: 10.1053/j.semnuclmed.2008.06.002] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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