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Kiss J, Balkay L, Kukuts K, Miko M, Forgacs A, Trencsenyi G, Krizsan AK. 3D printed anthropomorphic left ventricular myocardial phantom for nuclear medicine imaging applications. EJNMMI Phys 2022; 9:34. [PMID: 35503184 PMCID: PMC9065219 DOI: 10.1186/s40658-022-00461-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 04/20/2022] [Indexed: 11/26/2022] Open
Abstract
Background Anthropomorphic torso phantoms, including a cardiac insert, are frequently used to investigate the imaging performance of SPECT and PET systems. These phantom solutions are generally featuring a simple anatomical representation of the heart. 3D printing technology paves the way to create cardiac phantoms with more complex volume definition. This study aimed to describe how a fillable left ventricular myocardium (LVm) phantom can be manufactured using geometry extracted from a patient image. Methods The LVm of a healthy subject was segmented from 18F-FDG attenuation corrected PET image set. Two types of phantoms were created and 3D printed using polyethylene terephthalate glycol (PETG) material: one representing the original healthy LVm, and the other mimicking myocardium with a perfusion defect. The accuracy of the LVm phantom production was investigated by high-resolution CT scanning of 3 identical replicas. 99mTc SPECT acquisitions using local cardiac protocol were performed, without additional scattering media (“in air” measurements) for both phantom types. Furthermore, the healthy LVm phantom was inserted in the commercially available DataSpectrum Anthropomorphic Torso Phantom (“in torso” measurement) and measured with hot background and hot liver insert. Results Phantoms were easy to fill without any air-bubbles or leakage, were found to be reproducible and fully compatible with the torso phantom. Seventeen segments polar map analysis of the "in air” measurements revealed that a significant deficit in the distribution appeared where it was expected. 59% of polar map segments had less than 5% deviation for the "in torso” and "in air” measurement comparison. Excluding the deficit area, neither comparison had more than a 12.4% deviation. All the three polar maps showed similar apex and apical region values for all configurations. Conclusions Fillable anthropomorphic 3D printed phantom of LVm can be produced with high precision and reproducibility. The 3D printed LVm phantoms were found to be suitable for SPECT image quality tests during different imaging scenarios. The flexibility of the 3D printing process presented in this study provides scalable and anthropomorphic image quality phantoms in nuclear cardiology imaging.
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Affiliation(s)
- Janos Kiss
- Division of Radiology and Imaging Science, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary.
| | - Laszlo Balkay
- Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Kornel Kukuts
- ScanoMed Nuclear Medicine Centers, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Marton Miko
- Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Attila Forgacs
- ScanoMed Nuclear Medicine Centers, Nagyerdei krt. 98., Debrecen, 4032, Hungary.,Mediso Ltd., Laborc Utca 3., Budapest, 1037, Hungary
| | - Gyorgy Trencsenyi
- Division of Nuclear Medicine and Translational Imaging, Department of Medical Imaging, Faculty of Medicine, University of Debrecen, Nagyerdei krt. 98., Debrecen, 4032, Hungary
| | - Aron K Krizsan
- ScanoMed Nuclear Medicine Centers, Nagyerdei krt. 98., Debrecen, 4032, Hungary
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Steffen DA, Giannopoulos AA, Grossmann M, Messerli M, Schwyzer M, Gräni C, Gebhard C, Pazhenkottil AP, Kaufmann PA, Buechel RR. "Apical thinning": Relations between myocardial wall thickness and apical left ventricular tracer uptake as assessed with positron emission tomography myocardial perfusion imaging. J Nucl Cardiol 2020; 27:452-460. [PMID: 30109592 DOI: 10.1007/s12350-018-1397-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 07/27/2018] [Indexed: 02/05/2023]
Abstract
BACKGROUND A reduction in left ventricular apical tracer uptake (apical thinning) is frequently observed in myocardial perfusion imaging (MPI), yet its cause remains a matter of debate, particularly in perfusion emission tomography (PET). This analysis sought to determine whether apical thinning in PET-MPI is attributable to true anatomical thinning of the left ventricular apical myocardium. METHODS AND RESULTS We retrospectively analyzed 57 patients without any history or signs of apical myocardial infarction who underwent rest PET-MPI with 13N-ammonia and contrast-enhanced cardiac computed tomography (CT). Semi-quantitative normalized percent apical 13N-ammonia uptake at rest, myocardial blood flow (MBF), and k2 wash-out rate constants were compared to apical myocardial wall thickness measurements derived from CT and base-to-apex gradients were calculated. Apical thinning was found in 93% of patients and in 74% when analysis of normalized apical tracer uptake was confined to end-systole. No significant correlation was found between apical myocardial thickness and apical tracer uptake (r = - 0.080, P = .553), MBF (r = - 0.211, P = .115), or k2 wash-out rate (r = - 0.023, P = .872), nor between apical myocardial thickness and any gradients. A statistically significant but small difference in apical myocardial thickness was observed in patients with moderately to severely reduced apical tracer uptake vs patients with normal to mildly reduced uptake (4.3 ± 0.7 mm vs 4.7 ± 0.7 mm; P = .043). CONCLUSIONS Apical thinning is a highly prevalent finding during 13N-ammonia PET-MPI that is not solely attributable to true anatomical apical wall thickness or the partial volume effect. Other factors that yet need to be identified seem to have a more prominent impact.
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Affiliation(s)
- Dominik A Steffen
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Andreas A Giannopoulos
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Marvin Grossmann
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Michael Messerli
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Moritz Schwyzer
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Christoph Gräni
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Cathérine Gebhard
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Aju P Pazhenkottil
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Philipp A Kaufmann
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland
| | - Ronny R Buechel
- Department of Nuclear Medicine, Cardiac Imaging, University Hospital Zurich, Ramistrasse 100, 8091, Zurich, Switzerland.
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Shibutani T, Okuda K, Ichikawa H, Kato T, Miwa K, Tsushima H, Onoguchi M, Nagaki A. Imaging technology for myocardial perfusion single-photon emission computed tomography 2018 in Japan. Jpn J Radiol 2020; 38:274-282. [PMID: 31919636 DOI: 10.1007/s11604-019-00915-2] [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: 08/05/2019] [Accepted: 12/20/2019] [Indexed: 11/24/2022]
Abstract
AIM Recently, nuclear cardiology has dramatically advanced by a new technology development such as the device, short-term acquisition system, image reconstruction algorithm and image analysis. Although these innovations have been gradually employed in routine examinations, we did not investigate the current use of image acquisition, image reconstruction, and image analysis with myocardial perfusion single-photon emission computed tomography (MPS). We investigated the current status of MPS imaging technology in Japan. METHODS We carried out a survey using a Web-based questionnaire system, the opening of which was announced via e-mail, and it was available on a website for 3 months. We collected data on the current use of MPS with 201Tl and/or 99mTc agents with respect to routine protocols, image acquisition, image reconstruction, and image analysis. RESULTS We received responses to the Web-based questionnaire from 178 and 174 people for 99mTc and 201Tl MPS, respectively. The routine protocols of MPS of stress-rest and rest-stress MPS on 1-day protocols with 99mTc were 41.2% and 14.5%, respectively, and the rest-only scan response rate was 23.7%, whereas that of 201Tl MPS was 65.9% with stress-rest MPS, 19.0% with rest-only MPS, and 10.9% with stress-rest MPS adding a rest scan 24 h after injection. The filtered back projection (FBP) method is most commonly used image reconstruction method, yielding 70.5% for 99mTc MPS and 76.8% for 201Tl MPS, including combined FBP and ordered subset expectation maximization method. The results for no-correction (NC) images were 49.2% with 99mTc MPS and 55.2% with 201Tl MPS including the response of NC and combined attenuation correction (AC) and scatter correction (SC) (i.e., ACSC) images. The AC or ACSC images of 99mTc and 201Tl were provided by 30-40% of the institutions surveyed. CONCLUSIONS We investigated the current status of MPS imaging technology in Japan, and found that although the use of various technical developments has been reported, some of these technologies have not been utilized effectively. Hence, we expect that nuclear medicine technology will be used more effectively to improve diagnosis.
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Affiliation(s)
- Takayuki Shibutani
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80, Kodatsuno, Kanazawa, Ishikawa, Japan.
| | - Koichi Okuda
- Department of Physics, Kanazawa Medical University, Kahoku, Japan
| | - Hajime Ichikawa
- Department of Radiology, Toyohashi Municipal Hospital, Toyohashi, Japan
| | - Toyohiro Kato
- Department of Radiology, Toyohashi Municipal Hospital, Toyohashi, Japan
| | - Kenta Miwa
- Department of Radiological Sciences, School of Health Sciences, International University of Health and Welfare, Ohtawara, Japan
| | - Hiroyuki Tsushima
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, Ibaraki, Japan
| | - Masahisa Onoguchi
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80, Kodatsuno, Kanazawa, Ishikawa, Japan
| | - Akio Nagaki
- Department of Radiological Technology, Kurashiki Central Hospital, Kurashiki, Japan
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Pelletier-Galarneau M, Finnerty V, Tan S, Authier S, Gregoire J, Harel F. Assessment of left ventricular ejection fraction with cardiofocal collimators: Comparison between IQ-SPECT, planar equilibrium radionuclide angiography, and cardiac magnetic resonance. J Nucl Cardiol 2019; 26:1857-1864. [PMID: 29520572 DOI: 10.1007/s12350-018-1251-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 02/26/2018] [Indexed: 11/25/2022]
Abstract
BACKGROUND IQ-SPECT has been shown to significantly reduce acquisition time and administered dose while preserving image quality in myocardial perfusion imaging. Whether IQ-SPECT provides accurate left ventricular ejection fractions (LVEF) with gated blood pool SPECT (GBPS) remains unknown. METHODS Sixty patients underwent IQ-SPECT GBPS and planar imaging. Among those patients, 11 underwent both cMRI and GBPS. GBPS LVEF, LVEDV, and LVESV were calculated using 2 validated software; QBS (Cedars-Sinai Medical Center, Los Angeles, USA) and MHI (Montreal Heart Institute, Montreal, Canada). LVEF, LVEDV, and LVESV obtained with the different modalities were compared. RESULTS Average planar LVEF was 48 ± 11% (mean ± SD), average LVEDV was 177 ± 59 mL (range 63 to 342 mL), and average LVESV was 96 ± 46 mL (range 16 to 234 mL). GBPS LVEF and their correlation coefficient with planar LVEF were 40 ± 12% (r = 0.70) and 44 ± 12% (r = 0.83) with QBS and MHI, respectively. Correlation coefficient between cMRI and planar LVEF was 0.65 and were 0.69 and 0.52 between cMRI and GBPS using QBS and MHI, respectively. CONCLUSIONS LVEF calculated with GBPS using IQ-SPECT correlates with planar measurements. Correlation is best using the MHI method and variation is independent of LVEDV.
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Affiliation(s)
- Matthieu Pelletier-Galarneau
- Department of Radiology and Nuclear Medicine, Montreal Heart Institute, 5000 Belanger, Montreal, QC, H1T1C8, Canada.
| | - Vincent Finnerty
- Department of Radiology and Nuclear Medicine, Montreal Heart Institute, 5000 Belanger, Montreal, QC, H1T1C8, Canada
| | - Stephanie Tan
- Department of Radiology and Nuclear Medicine, Montreal Heart Institute, 5000 Belanger, Montreal, QC, H1T1C8, Canada
| | - Sebastien Authier
- Department of Radiology and Nuclear Medicine, Montreal Heart Institute, 5000 Belanger, Montreal, QC, H1T1C8, Canada
| | - Jean Gregoire
- Department of Radiology and Nuclear Medicine, Montreal Heart Institute, 5000 Belanger, Montreal, QC, H1T1C8, Canada
| | - Francois Harel
- Department of Radiology and Nuclear Medicine, Montreal Heart Institute, 5000 Belanger, Montreal, QC, H1T1C8, Canada
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Scabbio C, Zoccarato O, Malaspina S, Lucignani G, Del Sole A, Lecchi M. Impact of non-specific normal databases on perfusion quantification of low-dose myocardial SPECT studies. J Nucl Cardiol 2019; 26:775-785. [PMID: 29043555 DOI: 10.1007/s12350-017-1079-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/16/2017] [Indexed: 11/28/2022]
Abstract
AIM To evaluate the impact of non-specific normal databases on the percent summed rest score (SR%) and stress score (SS%) from simulated low-dose SPECT studies by shortening the acquisition time/projection. METHODS Forty normal-weight and 40 overweight/obese patients underwent myocardial studies with a conventional gamma-camera (BrightView, Philips) using three different acquisition times/projection: 30, 15, and 8 s (100%-counts, 50%-counts, and 25%-counts scan, respectively) and reconstructed using the iterative algorithm with resolution recovery (IRR) AstonishTM (Philips). Three sets of normal databases were used: (1) full-counts IRR; (2) half-counts IRR; and (3) full-counts traditional reconstruction algorithm database (TRAD). The impact of these databases and the acquired count statistics on the SR% and SS% was assessed by ANOVA analysis and Tukey test (P < 0.05). RESULTS Significantly higher SR% and SS% values (> 40%) were found for the full-counts TRAD databases respect to the IRR databases. For overweight/obese patients, significantly higher SS% values for 25%-counts scans (+19%) are confirmed compared to those of 50%-counts scan, independently of using the half-counts or the full-counts IRR databases. CONCLUSIONS AstonishTM requires the adoption of the own specific normal databases in order to prevent very high overestimation of both stress and rest perfusion scores. Conversely, the count statistics of the normal databases seems not to influence the quantification scores.
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Affiliation(s)
| | - Orazio Zoccarato
- Unit of Nuclear Medicine, I.C.S. Maugeri S.p.A. SB, Scientific Institute of Veruno IRCCS, Veruno, NO, Italy
| | - Simona Malaspina
- Nuclear Medicine Unit, Department of Diagnostic Services, ASST Santi Paolo e Carlo, Milan, Italy
| | - Giovanni Lucignani
- Nuclear Medicine Unit, Department of Diagnostic Services, ASST Santi Paolo e Carlo, Milan, Italy
- Department of Health Sciences, University of Milan, Milan, Italy
| | - Angelo Del Sole
- Nuclear Medicine Unit, Department of Diagnostic Services, ASST Santi Paolo e Carlo, Milan, Italy.
- Department of Health Sciences, University of Milan, Milan, Italy.
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Abstract
Cardiac SPECT continues to play a critical role in detecting and managing cardiovascular disease, in particularly coronary artery disease (CAD) (Jaarsma et al 2012 J. Am. Coll. Cardiol. 59 1719-28), (Agostini et al 2016 Eur. J. Nucl. Med. Mol. Imaging 43 2423-32). While conventional dual-head SPECT scanners using parallel-hole collimators and scintillation crystals with photomultiplier tubes are still the workhorse of cardiac SPECT, they have the limitations of low photon sensitivity (~130 count s-1 MBq-1), poor image resolution (~15 mm) (Imbert et al 2012 J. Nucl. Med. 53 1897-903), relatively long acquisition time, inefficient use of the detector, high radiation dose, etc. Recently our field observed an exciting growth of new developments of dedicated cardiac scanners and collimators, as well as novel imaging algorithms for quantitative cardiac SPECT. These developments have opened doors to new applications with potential clinical impact, including ultra-low-dose imaging, absolute quantification of myocardial blood flow (MBF) and coronary flow reserve (CFR), multi-radionuclide imaging, and improved image quality as a result of attenuation, scatter, motion, and partial volume corrections (PVCs). In this article, we review the recent advances in cardiac SPECT instrumentation and imaging methods. This review mainly focuses on the most recent developments published since 2012 and points to the future of cardiac SPECT from an imaging physics perspective.
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Affiliation(s)
- Jing Wu
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, United States of America
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7
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Lecchi M, Del Sole A. The long way to dose reduction in myocardial perfusion imaging. J Nucl Cardiol 2018; 25:2129-2132. [PMID: 28667453 DOI: 10.1007/s12350-017-0967-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 06/16/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Michela Lecchi
- Health Physics, San Paolo Hospital, University of Milan, Milan, Italy
| | - Angelo Del Sole
- Department of Health Sciences, University of Milan and Nuclear Medicine Unit, San Paolo Hospital, Milan, Italy.
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Characteristics of iodine-123 IQ-SPECT/CT imaging compared with conventional SPECT/CT. Ann Nucl Med 2018; 33:103-111. [PMID: 30324427 DOI: 10.1007/s12149-018-1310-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 10/08/2018] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Although the utility of IQ-SPECT imaging using 99mTc and 201Tl myocardial perfusion SPECT has been reported, 123I-labeled myocardial SPECT has not been fully evaluated. We determined the characteristics and utility of 123I IQ-SPECT imaging compared with conventional SPECT (C-SPECT). METHODS Two myocardial phantom patterns were used to simulate normal myocardium and myocardial infarction. SPECT acquisition was performed using a hybrid dual-head SPECT/CT system equipped with a SMARTZOOM collimator for IQ-SPECT or a low-medium energy general purpose collimator for C-SPECT. Projection data were reconstructed using ordered subset expectation maximization with depth-dependent 3-dimensional resolution recovery for C-SPECT and ordered subset conjugate gradient minimizer method for IQ-SPECT. Three types of myocardial image were created; namely, no correction (NC), with attenuation correction (AC), and with both attenuation and scatter corrections (ACSC). Five observers visually scored the homogeneity of normal myocardium and defect severity of the myocardium with inferior defects by a five-point scale: homogeneity scores (5 = homogeneous to 1 = inhomogeneous) and defect scores (5 = excellent to 1 = poor). We also created a 17-segment polar map and quantitatively assessed segmental %uptake using a myocardial phantom with normal findings and defects. RESULTS The average visual homogeneity scores of the IQ-SPECT with NC and ACSC were significantly higher than that of C-SPECT, whereas the average visual defect scores of IQ-SPECT with AC and ACSC were significantly lower. The %uptake of all segments for IQ-SPECT with NC was significantly higher than that of C-SPECT. Furthermore, the subtraction of %uptake for C-SPECT and IQ-SPECT was the largest in inferior wall, which was approximately 10.1%, 14.7% and 14.4% for NC, AC and ACSC, respectively. The median % uptake values of the inferior wall with defect areas for C-SPECT and IQ-SPECT were 46.9% and 50.7% with NC, 59.8% and 69.2% with AC, and 54.7% and 66.5% with ACSC, respectively. CONCLUSION 123I IQ-SPECT imaging significantly improved the attenuation artifact compared with C-SPECT imaging. Although the defect detectability of IQ-SPECT was inferior to that of C-SPECT, 123I IQ-SPECT images with NC and ACSC met the criteria for defect detectability. Use of 123I IQ-SPECT is suitable for routine examinations.
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Galt JR. New techniques, distinctive population, unique normal databases. J Nucl Cardiol 2018; 25:1338-1341. [PMID: 28474193 DOI: 10.1007/s12350-017-0876-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 03/27/2017] [Indexed: 10/19/2022]
Affiliation(s)
- James R Galt
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, 1364 Clifton Road, Atlanta, Georgia, 30322, USA.
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Otsuka R, Kubo N, Miyazaki Y, Kawahara M, Takaesu J, Fukuchi K. Current status of stress myocardial perfusion imaging pharmaceuticals and radiation exposure in Japan: Results from a nationwide survey. J Nucl Cardiol 2017; 24:1850-1855. [PMID: 28353211 DOI: 10.1007/s12350-017-0867-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 03/16/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND Ionizing radiation generated during medical imaging procedures is a matter of concern. However, the current status of radiopharmaceutical use in stress myocardial perfusion imaging (MPI) and the radiation exposure from these radiopharmaceuticals is unknown in Japan. METHODS AND RESULTS A nationwide survey was conducted from June through July 2016. The questionnaires on the radiopharmaceuticals used and their administered doses during stress MPI were sent to 641 nuclear medicine facilities. The responses were collected from 431 facilities and the effective dose (ED) for an adult with standard body weight was calculated. Forty-three percent of the facilities used only 201TlCl, 35% used only 99mTc radiopharmaceuticals, and the remaining 22% used both. The two main reasons for using 201TlCl instead of 99mTc radiopharmaceuticals were "more familiarity with the usage of 201TlCl than 99mTc radiopharmaceuticals" and "apprehension about increasing the burden of physicians performing tracer injection twice." The mean ED was 14.0 ± 5.5 mSv (range, 3.9 to 25.2 mSv), which was higher than that reported in other countries. CONCLUSIONS The ED of stress MPI radiopharmaceuticals in Japan is probably higher than the world standard because more than 50% of the facilities still use 201TlCl. We recommend revising the routine stress MPI protocol to reduce the effects of ionizing radiation.
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Affiliation(s)
- Ryuto Otsuka
- Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Narumi Kubo
- Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yosuke Miyazaki
- Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Mio Kawahara
- Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Jun Takaesu
- Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Kazuki Fukuchi
- Division of Medical Technology and Science, Department of Medical Physics and Engineering, Course of Health Science, Osaka University Graduate School of Medicine, 1-7 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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Nakajima K, Okuda K, Momose M, Matsuo S, Kondo C, Sarai M, Shibutani T, Onoguchi M, Shimizu T, Vija AH. IQ·SPECT technology and its clinical applications using multicenter normal databases. Ann Nucl Med 2017; 31:649-659. [PMID: 28940141 PMCID: PMC5651712 DOI: 10.1007/s12149-017-1210-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Accepted: 09/11/2017] [Indexed: 11/26/2022]
Abstract
IQ·SPECT (Siemens Medical Solutions) is a solution for high-sensitivity and short-time acquisition imaging of the heart for a variable angle general purpose gamma camera. It consists of a multi-focal collimator, a cardio-centric orbit and advanced iterative reconstruction, modeling the image formation physics accurately. The multi-focal collimator enables distance-dependent enlargement of the center region while avoiding truncation at the edges. With the specified configuration and a cardio-centric orbit it can obtain a fourfold sensitivity increase for the heart at the center of the scan orbit. Since IQ·SPECT shows characteristic distribution patterns in the myocardium, appropriate acquisition and processing conditions are required, and normal databases are convenient for quantification of both normal and abnormal perfusion images. The use of prone imaging can be a good option when X-ray computed tomography (CT) is not available for attenuation correction. CT-based attenuation correction changes count distribution significantly in the inferior wall and around the apex, hence image interpretation training and additional use of normal databases are recommended. Recent reports regarding its technology, Japanese Society of Nuclear Medicine working group activities, and clinical studies using 201Tl and 99mTc-perfusion tracers in Japan are summarized.
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Affiliation(s)
- Kenichi Nakajima
- Department of Nuclear Medicine, Kanazawa University, 13-1 Takara-machi, Kanazawa, 920-8641, Japan.
| | - Koichi Okuda
- Department of Physics, Kanazawa Medical University, Uchinada, Kahoku, Japan
| | - Mitsuru Momose
- Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Woman's Medical University, Tokyo, Japan
| | - Shinro Matsuo
- Department of Nuclear Medicine, Kanazawa University, 13-1 Takara-machi, Kanazawa, 920-8641, Japan
| | - Chisato Kondo
- Department of Diagnostic Imaging and Nuclear Medicine, Tokyo Woman's Medical University, Tokyo, Japan
- Koishikawa Yanagimachi Clinic, Tokyo, Japan
| | - Masayoshi Sarai
- Department of Cardiology, Fujita Health University Hospital, Toyoake, Japan
| | - Takayuki Shibutani
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Masahisa Onoguchi
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | | | - A Hans Vija
- Siemens Medical Solution USA, Inc., Molecular Imaging, Hoffman Estates, IL, USA
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Konishi T, Nakajima K, Okuda K, Yoneyama H, Matsuo S, Shibutani T, Onoguchi M, Kinuya S. IQ-SPECT for thallium-201 myocardial perfusion imaging: effect of normal databases on quantification. Ann Nucl Med 2017; 31:454-461. [PMID: 28405882 DOI: 10.1007/s12149-017-1170-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 04/03/2017] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Although IQ-single-photon emission computed tomography (SPECT) provides rapid acquisition and attenuation-corrected images, the unique technology may create characteristic distribution different from the conventional imaging. This study aimed to compare the diagnostic performance of IQ-SPECT using Japanese normal databases (NDBs) with that of the conventional SPECT for thallium-201 (201Tl) myocardial perfusion imaging (MPI). METHODS A total of 36 patients underwent 1-day 201Tl adenosine stress-rest MPI. Images were acquired with IQ-SPECT at approximately one-quarter of the standard time of conventional SPECT. Projection data acquired with the IQ-SPECT system were reconstructed via an ordered subset conjugate gradient minimizer method with or without scatter and attenuation correction (SCAC). Projection data obtained using the conventional SPECT were reconstructed via a filtered back projection method without SCAC. The summed stress score (SSS) was calculated using NDBs created by the Japanese Society of Nuclear Medicine working group, and scores were compared between IQ-SPECT and conventional SPECT using the acquisition condition-matched NDBs. The diagnostic performance of the methods for the detection of coronary artery disease was also compared. RESULTS SSSs were 6.6 ± 8.2 for the conventional SPECT, 6.6 ± 9.4 for IQ-SPECT without SCAC, and 6.5 ± 9.7 for IQ-SPECT with SCAC (p = n.s. for each comparison). The SSS showed a strong positive correlation between conventional SPECT and IQ-SPECT (r = 0.921 and p < 0.0001), and the correlation between IQ-SPECT with and without SCAC was also good (r = 0.907 and p < 0.0001). Regarding diagnostic performance, the sensitivity, specificity, and accuracy were 80.8, 78.9, and 79.4%, respectively, for the conventional SPECT; 80.8, 80.3, and 82.0%, respectively, for IQ-SPECT without SCAC; and 88.5, 86.8, and 87.3%, respectively, for IQ-SPECT with SCAC, respectively. The area under the curve obtained via receiver operating characteristic analysis were 0.77, 0.80, and 0.86 for conventional SPECT, IQ-SPECT without SCAC, and IQ-SPECT with SCAC, respectively (p = n.s. for each comparison). CONCLUSIONS When appropriate NDBs were used, the diagnostic performance of 201Tl IQ-SPECT was comparable with that of the conventional system regardless of different characteristics of myocardial accumulation in the conventional system.
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Affiliation(s)
- Takahiro Konishi
- Department of Radiology, Kanazawa University Hospital, 13-1 Takara-machi, Kanazawa, 920-8641, Japan
| | - Kenichi Nakajima
- Department of Nuclear Medicine, Kanazawa University Hospital, 13-1 Takara-machi, Kanazawa, 920-8641, Japan.
| | - Koichi Okuda
- Department of Physics, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Kahoku, Ishikawa, 920-0293, Japan
| | - Hiroto Yoneyama
- Department of Radiology, Kanazawa University Hospital, 13-1 Takara-machi, Kanazawa, 920-8641, Japan
| | - Shinro Matsuo
- Department of Nuclear Medicine, Kanazawa University Hospital, 13-1 Takara-machi, Kanazawa, 920-8641, Japan
| | - Takayuki Shibutani
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa, 920-0942, Japan
| | - Masahisa Onoguchi
- Department of Quantum Medical Technology, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa, 920-0942, Japan
| | - Seigo Kinuya
- Department of Nuclear Medicine, Kanazawa University Hospital, 13-1 Takara-machi, Kanazawa, 920-8641, Japan
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