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Автор: Grafiati

Опубліковано: 7 липня 2024

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1

Bouchareb, Yassine, Afrah AlSaadi, Jawa Zabah, Anjali Jain, Aziza Al-Jabri, Peter Phiri, Jian Qing Shi, Gayathri Delanerolle, and Srinivasa Rao Sirasanagandla. "Technological Advances in SPECT and SPECT/CT Imaging." Diagnostics 14, no. 13 (July 4, 2024): 1431. http://dx.doi.org/10.3390/diagnostics14131431.

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Single photon emission tomography/computed tomography (SPECT/CT) is a mature imaging technology with a dynamic role in the diagnosis and monitoring of a wide array of diseases. This paper reviews the technological advances, clinical impact, and future directions of SPECT and SPECT/CT imaging. The focus of this review is on signal amplifier devices, detector materials, camera head and collimator designs, image reconstruction techniques, and quantitative methods. Bulky photomultiplier tubes (PMTs) are being replaced by position-sensitive PMTs (PSPMTs), avalanche photodiodes (APDs), and silicon PMs to achieve higher detection efficiency and improved energy resolution and spatial resolution. Most recently, new SPECT cameras have been designed for cardiac imaging. The new design involves using specialised collimators in conjunction with conventional sodium iodide detectors (NaI(Tl)) or an L-shaped camera head, which utilises semiconductor detector materials such as CdZnTe (CZT: cadmium–zinc–telluride). The clinical benefits of the new design include shorter scanning times, improved image quality, enhanced patient comfort, reduced claustrophobic effects, and decreased overall size, particularly in specialised clinical centres. These noticeable improvements are also attributed to the implementation of resolution-recovery iterative reconstructions. Immense efforts have been made to establish SPECT and SPECT/CT imaging as quantitative tools by incorporating camera-specific modelling. Moreover, this review includes clinical examples in oncology, neurology, cardiology, musculoskeletal, and infection, demonstrating the impact of these advancements on clinical practice in radiology and molecular imaging departments.

2

Cantoni, Valeria, Roberta Green, Carlo Ricciardi, Roberta Assante, Leandro Donisi, Emilia Zampella, Giuseppe Cesarelli, et al. "Comparing the Prognostic Value of Stress Myocardial Perfusion Imaging by Conventional and Cadmium-Zinc Telluride Single-Photon Emission Computed Tomography through a Machine Learning Approach." Computational and Mathematical Methods in Medicine 2021 (October 16, 2021): 1–8. http://dx.doi.org/10.1155/2021/5288844.

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We compared the prognostic value of myocardial perfusion imaging (MPI) by conventional- (C-) single-photon emission computed tomography (SPECT) and cadmium-zinc-telluride- (CZT-) SPECT in a cohort of patients with suspected or known coronary artery disease (CAD) using machine learning (ML) algorithms. A total of 453 consecutive patients underwent stress MPI by both C-SPECT and CZT-SPECT. The outcome was a composite end point of all-cause death, cardiac death, nonfatal myocardial infarction, or coronary revascularization procedures whichever occurred first. ML analysis performed through the implementation of random forest (RF) and k -nearest neighbors (KNN) algorithms proved that CZT-SPECT has greater accuracy than C-SPECT in detecting CAD. For both algorithms, the sensitivity of CZT-SPECT (96% for RF and 60% for KNN) was greater than that of C-SPECT (88% for RF and 53% for KNN). A preliminary univariate analysis was performed through Mann-Whitney tests separately on the features of each camera in order to understand which ones could distinguish patients who will experience an adverse event from those who will not. Then, a machine learning analysis was performed by using Matlab (v. 2019b). Tree, KNN, support vector machine (SVM), Naïve Bayes, and RF were implemented twice: first, the analysis was performed on the as-is dataset; then, since the dataset was imbalanced (patients experiencing an adverse event were lower than the others), the analysis was performed again after balancing the classes through the Synthetic Minority Oversampling Technique. According to KNN and SVM with and without balancing the classes, the accuracy ( p value = 0.02 and p value = 0.01) and recall ( p value = 0.001 and p value = 0.03) of the CZT-SPECT were greater than those obtained by C-SPECT in a statistically significant way. ML approach showed that although the prognostic value of stress MPI by C-SPECT and CZT-SPECT is comparable, CZT-SPECT seems to have higher accuracy and recall.

3

Weng, Fenghua, Srijeeta Bagchi, Yunlong Zan, Qiu Huang, and Youngho Seo. "An energy-optimized collimator design for a CZT-based SPECT camera." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 806 (January 2016): 330–39. http://dx.doi.org/10.1016/j.nima.2015.09.115.

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4

Duvall, W. Lane, Lori B. Croft, Tapan Godiwala, Eric Ginsberg, Titus George, and Milena J. Henzlova. "Reduced isotope dose with rapid SPECT MPI imaging: Initial experience with a CZT SPECT camera." Journal of Nuclear Cardiology 17, no. 6 (November 12, 2010): 1009–14. http://dx.doi.org/10.1007/s12350-010-9215-5.

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5

Duvall, W. Lane, Lori B. Croft, Eric S. Ginsberg, Andrew J. Einstein, Krista A. Guma, Titus George, and Milena J. Henzlova. "Reduced isotope dose and imaging time with a high-efficiency CZT SPECT camera." Journal of Nuclear Cardiology 18, no. 5 (April 29, 2011): 847–57. http://dx.doi.org/10.1007/s12350-011-9379-7.

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6

Hansen, Maria Normand, Christian Haarmark, Bent Kristensen, and Bo Zerahn. "An Algorithm for Individual Dosage in Cadmium–Zinc–Telluride SPECT-Gated Radionuclide Angiography." Diagnostics 11, no. 12 (December 4, 2021): 2268. http://dx.doi.org/10.3390/diagnostics11122268.

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The aim of the present study was to test an individualised dose without compromising the ease of analysing data when performing equilibrium radionuclide angiography (ERNA) using cadmium–zinc–telluride (CZT) SPECT. From March 2018 to January 2019, 1650 patients referred for ERNA received either an individualised dose of 99mTc-labeled human serum albumin (HSA) according to their age, sex, height, and weight (n = 1567), or a standard dose of 550 MBq (n = 83). The target count rate (CRT) was reduced every two months from 2.7 to 1.0 kcps. A final test with a CRT of 1.7 kcps was run for three months to test whether an agreement within 2% points for the determination of LVEF, on the basis of only two analyses, was obtainable in at least 95% of acquisitions. All the included ERNAs were performed on a dedicated cardiac CZT SPECT camera. When using the algorithm for an individualised dose, we found that agreement between the measured and predicted count rate was 80%. With a CRT of 1.7 kcps, the need for more than two analyses to obtain sufficient agreement for LVEF was 4.9%. Furthermore, this resulted in a mean dose reduction from 550 to 258 MBq. Patients’ weight, height, sex, and age can, therefore, be used for individualising a tracer dose while reducing the mean dose.

7

Yoo, Ik Dong, In Young Jo, Geum Cheol Jeong, Yong Kyun Won, Du Shin Jeong, and Sang Mi Lee. "Quantitative Scintigraphy Imaging of Lingual Raynaud’s Phenomenon Using 3-Dimensional-Ring Cadmium-Zinc-Telluride Single-Photon Emission Computed Tomography/Computed Tomography." Tomography 8, no. 4 (August 17, 2022): 2042–48. http://dx.doi.org/10.3390/tomography8040171.

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Perfusion scintigraphy with the acquisition of planar blood flow and pool images of bilateral hands has been used to aid diagnosis and to evaluate treatment response to Raynaud’s phenomenon (decreased blood flow to hand or foot). However, because of the difficulty in imaging the tongue area with a conventional gamma camera, perfusion scintigraphy imaging of patients with lingual Raynaud’s phenomenon has yet to be reported. Here, we report the case of a 59-year-old man with lingual Raynaud’s phenomenon in which blood pool imaging of the tongue was performed using three-dimensional (3D)-ring cadmium-zinc-telluride (CZT) single-photon emission computed tomography/computed tomography (SPECT/CT). During follow-up, the patient’s lingual symptoms had worsened, and follow-up blood pool SPECT/CT images also revealed decreased blood pool uptake of the tongue, showing a decreased blood pool of more than 25% on quantitative analysis. This case suggests that blood pool imaging of the tongue using 3D-ring CZT SPECT/CT has clinical significance in evaluating patients with lingual Raynaud’s phenomenon.

8

Hindorf, Cecilia, Jenny Oddstig, Fredrik Hedeer, Magnus J. Hansson, Jonas Jögi, and Henrik Engblom. "Importance of correct patient positioning in myocardial perfusion SPECT when using a CZT camera." Journal of Nuclear Cardiology 21, no. 4 (May 8, 2014): 695–702. http://dx.doi.org/10.1007/s12350-014-9897-1.

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9

Lima, Ronaldo, Thais Peclat, Thalita Soares, Caio Ferreira, Ana Carolina Souza, and Gabriel Camargo. "Comparison of the prognostic value of myocardial perfusion imaging using a CZT-SPECT camera with a conventional anger camera." Journal of Nuclear Cardiology 24, no. 1 (August 10, 2016): 245–51. http://dx.doi.org/10.1007/s12350-016-0618-9.

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10

Piatkova, Yuliya, Pierre Payoux, Caroline Boursier, Manon Bordonne, Veronique Roch, Pierre-Yves Marie, Gabriela Hossu, Laëtitia Imbert, and Antoine Verger. "Prospective Paired Comparison of 123I-FP-CIT SPECT Images Obtained With a 360°-CZT and a Conventional Camera." Clinical Nuclear Medicine 47, no. 1 (January 2022): 14–20. http://dx.doi.org/10.1097/rlu.0000000000003969.

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11

Lima, Ronaldo S. L., Thaís R. Peclat, Ana Carolina A. H. Souza, Aline M. K. Nakamoto, Felipe M. Neves, Victor F. Souza, Letícia B. Glerian, and Andrea De Lorenzo. "Prognostic value of a faster, low-radiation myocardial perfusion SPECT protocol in a CZT camera." International Journal of Cardiovascular Imaging 33, no. 12 (June 29, 2017): 2049–56. http://dx.doi.org/10.1007/s10554-017-1202-3.

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12

Boutaghane, Nasreddine, Michel Hesse, Boualem Bouzid, Habib Zaidi, François Jamar, and Stephan Walrand. "Dual-layer collimator for improved spatial resolution in SPECT with CZT camera: an analytical and Monte Carlo study." Physics in Medicine & Biology 67, no. 6 (March 11, 2022): 065006. http://dx.doi.org/10.1088/1361-6560/ac5671.

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Abstract Purpose. Current hole matching pixel detector (HMPD) collimators for SPECT imaging exist in two configurations: one hole per pixel (1HMPD) or four holes per pixel (4HMPD). The aim of this study was to assess the performance of a dual-layer collimator made by stacking up these two collimator types (1H/4HMDP) for low- and medium energy gamma emitters. Method. Analytical equations describing geometrical efficiency and full width at half maximum (FWHM) of the 1H/4HMDP collimator were derived. In addition, a fast dedicated Monte Carlo (MC) code neglecting scattering and designed for the collimator geometry was developed to assess the collimator’s point spread function and to simulate planar and SPECT acquisitions. Results. A relative agreement between analytical equations and MC simulations better than 3% was observed for the efficiency and for the FWHM. The length of the two layers was optimized to get the best spatial resolution while keeping the geometrical efficiency equal to that of the 45 mm length 1HMPD collimator. An optimized combination of the 1H/4HMPD configuration with respective hole lengths of 20 and 13 mm has been derived. For source-collimator distances above 5 cm and equal collimator geometrical efficiency, the spatial resolution of this optimal 1H/4HMDP collimator supersedes that of the 45 mm length 1HMPD collimator, and that of the 19.1 mm length 4HMPD collimator. This improvement was observed in simulations of bar phantom planar images and of hot rods phantom SPECT. Remarkably, the spatial resolution was preserved along the whole radial range within the Jaszczak phantom. Conclusion. The 1H/4HMDP collimator is a promising solution for CZT SPECT imaging of low- and medium energy emitters.

13

Bordonne, Manon, Pierre-Yves Marie, Laetitia Imbert, and Antoine Verger. "Brain perfusion SPECT acquired using a dedicated brain configuration on a 360° whole-body CZT-camera." Journal of Neuroradiology 47, no. 2 (March 2020): 180–81. http://dx.doi.org/10.1016/j.neurad.2019.11.002.

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14

Legallois, Damien, Laure Champ-Rigot, Benjamin Houdu, Denis Agostini, and Alain Manrique. "Ventricular arrhythmia originating from scar border tissue during dobutamine myocardial perfusion gated SPECT on CZT camera." Journal of Nuclear Cardiology 23, no. 4 (December 3, 2015): 854–55. http://dx.doi.org/10.1007/s12350-015-0356-4.

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15

Verger, Antoine, Laetitia Imbert, Yalcine Yagdigul, Renaud Fay, Wassila Djaballah, François Rouzet, Nicolas Fourquet, et al. "Factors affecting the myocardial activity acquired during exercise SPECT with a high-sensitivity cardiac CZT camera as compared with conventional Anger camera." European Journal of Nuclear Medicine and Molecular Imaging 41, no. 3 (November 8, 2013): 522–28. http://dx.doi.org/10.1007/s00259-013-2617-2.

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16

Zeng, Gengsheng L., and Daniel Gagnon. "Image reconstruction algorithm for a spinning strip CZT SPECT camera with a parallel slat collimator and small pixels." Medical Physics 31, no. 12 (November 23, 2004): 3461–73. http://dx.doi.org/10.1118/1.1813873.

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17

van Dijk, Joris D., Jorn A. van Dalen, Mohamed Mouden, Jan Paul Ottervanger, Siert Knollema, Cornelis H. Slump, and Pieter L. Jager. "Value of automatic patient motion detection and correction in myocardial perfusion imaging using a CZT-based SPECT camera." Journal of Nuclear Cardiology 25, no. 2 (July 12, 2016): 419–28. http://dx.doi.org/10.1007/s12350-016-0571-7.

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18

Jurczak, J., L. Imbert, G. Karcher, and P. Y. Marie. "P2. Impact of the modelling of charge collection on the simulation of SPECT recordings from CZT semiconductors camera." Physica Medica 32 (December 2016): 367–68. http://dx.doi.org/10.1016/j.ejmp.2016.11.014.

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19

Chevalier, Elodie, Caroline Boursier, Marine Claudin, Pierre-Yves Marie, and Laetitia Imbert. "Feasibility of 177Lu Therapy Monitoring Using Fast Whole-Body SPECT Recordings Provided by a High-Speed 360° CZT Camera." Clinical Nuclear Medicine 45, no. 11 (June 26, 2020): e493-e494. http://dx.doi.org/10.1097/rlu.0000000000003169.

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20

Luo, J., N. Deitz, D. Pantelic, D. Cowling, and S. Jang. "SU-E-I-179: Evaluation of a SPECT Camera with CZT Detectors and Multipinhole Collimator for Nuclear Cardiology Imaging." Medical Physics 38, no. 6Part6 (June 2011): 3437. http://dx.doi.org/10.1118/1.3611753.

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21

Mouden, Mohamed, Jorik R. Timmer, Jan Paul Ottervanger, Stoffer Reiffers, Ad H. J. Oostdijk, Siert Knollema, and Pieter L. Jager. "Impact of a new ultrafast CZT SPECT camera for myocardial perfusion imaging: fewer equivocal results and lower radiation dose." European Journal of Nuclear Medicine and Molecular Imaging 39, no. 6 (March 17, 2012): 1048–55. http://dx.doi.org/10.1007/s00259-012-2086-z.

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22

Cichocki, Paweł, Michał Błaszczyk, Kamila Cygulska, Krzysztof Filipczak, Zbigniew Adamczewski, Jacek Kuśmierek, Piotr Lipiec, Jarosław Damian Kasprzak, and Anna Płachcińska. "Inter- and Intraobserver Repeatability of Myocardial Flow Reserve Values Determined with SPECT Study Using a Discovery NM530c Camera and Corridor 4DM Software." Journal of Personalized Medicine 11, no. 11 (November 9, 2021): 1164. http://dx.doi.org/10.3390/jpm11111164.

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Background: Myocardial blood flow (MBF) and flow reserve (MFR) examination, especially useful in the diagnosis of multivessel coronary artery disease (CAD), can be assessed with a cadmium-zinc-telluride (CZT) SPECT gamma camera, as an alternative to the expensive and less available PET. However, study processing is not free from subjective factors. Therefore, this paper aims to evaluate intra- and interobserver repeatability of MBF and MFR values obtained by the same operator and two independent operators. Methods: This study included 57 adult patients. MBF and MFR were assessed using a Discovery NM530c camera in a two-day, rest/dipyridamople protocol, using 99mTc-MIBI. Data were processed using Corridor4DM software, twice by one operator and once by another operator. Results: The repeatability of the assessed values was quite good in the whole myocardium, LAD and LCX vascular territories, but was poor in the RCA territory. Conclusions: The poor repeatability of MBF and MFR in RCA vascular territory can be explained by poor automatic orientation of the heart axis during post-processing and a so-called “cardiac creep” phenomenon. Better automatic heart orientation and introduction of automatic motion correction is likely to drastically improve this repeatability. In the present state of the software, PET is better for patients requiring assessment of MFR in the RCA territory.

23

Ben Bouallègue, Fayçal, Catherine Nganoa, Jonathan Vigne, Denis Agostini, and Alain Manrique. "Comparative Performances of Dipyridamole and Regadenoson to Detect Myocardial Ischemia using Cardiac Cadmium-Zinc-Telluride Single-Photon Emission Computerized Tomography." Journal of Clinical Imaging Science 8 (November 15, 2018): 51. http://dx.doi.org/10.4103/jcis.jcis_71_17.

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Objective: We evaluated the relative performances of dipyridamole (Dip) and regadenoson (Reg) in a cohort of patients referred for coronary artery disease diagnosis or follow-up using myocardial perfusion imaging. Materials and Methods: We retrospectively included 515 consecutive patients referred for 99mTc-sestamibi myocardial perfusion single-photon emission computerized tomography (SPECT) on a cadmium-zinc-telluride (CZT) camera after pharmacologic stress. About three quarters (n = 391, 76%) received Dip. Reg was administrated to patients with chronical respiratory disease or with body mass index (BMI) over 38 kg/m2 (n = 124, 24%). Patients with an abnormal stress scan (92%) underwent a rest imaging on the same day. Qualitative interpretation of perfusion images was achieved using QPS software, and the ischemic area was assessed using the 17-segment model. In patients undergoing a stress-rest protocol, perfusion polar plots were postprocessed using automated in-house software to quantify the extension, intensity, and location of the reversible perfusion defect. Statistical comparison between groups was performed using univariate and multivariate analysis. Results: Qualitative analysis concluded to myocardial ischemia in 70% of the patients (69% in the Dip group, 76% in the Reg group, P = ns). In those patients, the number of involved segments (Dip 2.5 ± 1.6, Reg 2.7 ± 1.6, P = ns) and the proportion of patients with an ischemic area larger than two segments (Dip 30%, Reg 37%, P = ns) were comparable. Automated quantification of the reversible perfusion defect demonstrated similar defect extension, intensity, and severity in the two groups. Defect location was identical at the myocardial segment and vascular territory scales. Conclusions: Reg and Dip showed equal performances for ischemic burden characterization using myocardial CZT SPECT.

24

Franc, Benjamin L., Yonggang Cui, Seth A. Rosenthal, Tammie Johnston, Uday Poonamallee, Jason B. Wiesner, Kristen MN Vandewalker, Youngho Seo, Terrance Lall, and Ralph James. "Improved techniques to localize foci of carcinoma within the prostate using high-resolution transrectal gamma imaging (TRGI) of monoclonal antibody directed at prostate specific membrane antigen (PSMA)." Journal of Clinical Oncology 30, no. 15_suppl (May 20, 2012): e21026-e21026. http://dx.doi.org/10.1200/jco.2012.30.15_suppl.e21026.

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e21026 Background: As many as 40% of prostate cancers may be missed on biopsy, necessitating novel methods for biopsy guidance. There is also interest in mapping primary prostate cancers for treatment. The presented work evaluated the ability of a transrectal gamma-imaging (TRGI) device to detect and localize a prostate-specific membrane antigen (PSMA) - specific radiopharmaceutical in the prostate. Methods: The IRB approved this exploratory proof-of-concept study. Male patients with untreated, biopsy-proven prostatic adenocarcinoma received 5±0.5 mCi In-111 capromab pendetide (Prostascint, a PSMA-specific agent) i.v. and were imaged 4 days later using single photon emission computed tomography (SPECT-CT). A commercially available cadmium zinc telluride (CZT)-based endorectal gamma camera (ProxiScanTM, Hybridyne Imaging Technologies, Inc.) determined the radiopharmaceutical’s planar distribution (1.5x4 cm FOV; 5 min acquisition) in four prostatic quadrants. Safety assessments occurred day 1 and 7. MRI was acquired within 14 days. Pathology from TRUS biopsy or following prostatectomy identified prostatic quadrants containing adenocarcinoma. Results: Of 8 patients recruited, 6 completed imaging, all without adverse event. Subsequent treatment included prostatectomy (n=3) and radiation (n=3). Twenty-three prostatic quadrants were evaluated. In detecting a cancer-containing quadrant, TRGI, SPECT, and MRI had sensitivities of 100%, 75%, and 33%, respectively, and similar accuracy (61-70%). Target-to-background signal ratio of TRGI was independent of serum PSA level and not significantly different than SPECT. TRGI identified a greater number of foci in each quadrant when compared with SPECT (p<0.001). Lesion sizes on TRGI were smaller (p=0.04) and correlated with cancer size on pathology in patients treated surgically (r=0.69), identifying tracer uptake associated with tumors ≥ 5 mm. Conclusions: TRGI provides improved localization of prostate carcinoma compared with conventional SPECT with potential implications for the diagnosis and treatment of prostate cancer.

25

Esteves, Fabio P., James R. Galt, Russell D. Folks, Liudmila Verdes, and Ernest V. Garcia. "Diagnostic performance of low-dose rest/stress Tc-99m tetrofosmin myocardial perfusion SPECT using the 530c CZT camera: Quantitative vs visual analysis." Journal of Nuclear Cardiology 21, no. 1 (November 28, 2013): 158–65. http://dx.doi.org/10.1007/s12350-013-9827-7.

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26

Wells, RG, K. Vanderwerf, I. Ali, and TD Ruddy. "Poster - Thur Eve - 02: Evaluation of Cross-Talk for Dual-Isotope Myocardial Perfusion Imaging Using a New Dedicated Cardiac CZT SPECT Camera." Medical Physics 37, no. 7Part1 (July 2010): 3886. http://dx.doi.org/10.1118/1.3476107.

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27

Melki, Saifeddine, Mohammad Bilal Chawki, Pierre-Yves Marie, Laetitia Imbert, and Antoine Verger. "Augmented planar bone scintigraphy obtained from a whole-body SPECT recording of less than 20 min with a high-sensitivity 360° CZT camera." European Journal of Nuclear Medicine and Molecular Imaging 47, no. 5 (October 12, 2019): 1329–31. http://dx.doi.org/10.1007/s00259-019-04525-y.

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28

Morelle, Maxime, Dimitri Bellevre, Claude Hossein-Foucher, Alain Manrique, and Alban Bailliez. "First comparison of performances between the new whole-body cadmium–zinc–telluride SPECT-CT camera and a dedicated cardiac CZT camera for myocardial perfusion imaging: Analysis of phantom and patients." Journal of Nuclear Cardiology 27, no. 4 (April 8, 2019): 1261–69. http://dx.doi.org/10.1007/s12350-019-01702-2.

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29

Giorgetti, Assuero, Pier Giorgio Masci, Gavino Marras, Yasmine K. Rustamova, Alessia Gimelli, Dario Genovesi, Massimo Lombardi, and Paolo Marzullo. "Gated SPECT evaluation of left ventricular function using a CZT camera and a fast low-dose clinical protocol: comparison to cardiac magnetic resonance imaging." European Journal of Nuclear Medicine and Molecular Imaging 40, no. 12 (July 25, 2013): 1869–75. http://dx.doi.org/10.1007/s00259-013-2505-9.

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30

Legagneur, Corinne, Loïc Djaileb, Caroline Sagnes, Alex Calizzano, Estelle Vautrin, Jean-Louis Quesada, Alexis Broisat, et al. "0005 : Prognostic value of myocardial perfusion SPECT without significant perfusion defect using a dual isotope protocol and a novel CZT camera: interim results of the PROMHETE study." Archives of Cardiovascular Diseases Supplements 8, no. 3 (April 2016): 254. http://dx.doi.org/10.1016/s1878-6480(16)30499-2.

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Bailliez, Alban, Tanguy Blaire, Frédéric Mouquet, R. Legghe, B. Etienne, Damien Legallois, Denis Agostini, and Alain Manrique. "Segmental and global left ventricular function assessment using gated SPECT with a semiconductor Cadmium Zinc Telluride (CZT) camera: Phantom study and clinical validation vs cardiac magnetic resonance." Journal of Nuclear Cardiology 21, no. 4 (May 9, 2014): 712–22. http://dx.doi.org/10.1007/s12350-014-9899-z.

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Sharir, Tali, Marina Pinskiy, Abraham Pardes, Arik Rochman, Vitali Prokhorov, Gil Kovalski, Konstantine Merzon, Andrzej Bojko, and Boris Brodkin. "Comparison of the diagnostic accuracies of very low stress-dose with standard-dose myocardial perfusion imaging: Automated quantification of one-day, stress-first SPECT using a CZT camera." Journal of Nuclear Cardiology 23, no. 1 (May 27, 2015): 11–20. http://dx.doi.org/10.1007/s12350-015-0130-7.

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Hyafil, Fabien, Renata Chequer, Emmanuel Sorbets, Candice Estellat, Gregory Ducrocq, François Rouzet, Toni Alfaiate, et al. "Head-to-head comparison of the diagnostic performances of Rubidium-PET and SPECT with CZT camera for the detection of myocardial ischemia in a population of women and overweight individuals." Journal of Nuclear Cardiology 27, no. 3 (December 20, 2018): 755–68. http://dx.doi.org/10.1007/s12350-018-01557-z.

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Yamamoto, Atsushi, Michinobu Nagao, Kiyoe Ando, Risako Nakao, Yuka Matsuo, Akiko Sakai, Mitsuru Momose, Koichiro Kaneko, Nobuhisa Hagiwara, and Shuji Sakai. "First Validation of Myocardial Flow Reserve Derived from Dynamic <sup>99m</sup>Tc-Sestamibi CZT-SPECT Camera Compared with <sup>13</sup>N-Ammonia PET." International Heart Journal 63, no. 2 (March 30, 2022): 202–9. http://dx.doi.org/10.1536/ihj.21-487.

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D’estanque, Emmanuel, Christophe Hedon, Benoît Lattuca, Aurélie Bourdon, Meriem Benkiran, Aurélie Verd, François Roubille, and Denis Mariano-Goulart. "Optimization of a simultaneous dual-isotope 201Tl/123I-MIBG myocardial SPECT imaging protocol with a CZT camera for trigger zone assessment after myocardial infarction for routine clinical settings: Are delayed acquisition and scatter correction necessary?" Journal of Nuclear Cardiology 24, no. 4 (May 25, 2016): 1361–69. http://dx.doi.org/10.1007/s12350-016-0524-1.

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Agostini, Denis, Vincent Roule, Catherine Nganoa, Nathaniel Roth, Raphael Baavour, Jean-Jacques Parienti, Farzin Beygui, and Alain Manrique. "First validation of myocardial flow reserve assessed by dynamic 99mTc-sestamibi CZT-SPECT camera: head to head comparison with 15O-water PET and fractional flow reserve in patients with suspected coronary artery disease. The WATERDAY study." European Journal of Nuclear Medicine and Molecular Imaging 45, no. 7 (March 1, 2018): 1079–90. http://dx.doi.org/10.1007/s00259-018-3958-7.

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Imbert, Laetitia, and Pierre-Yves Marie. "CZT cameras: A technological jump for myocardial perfusion SPECT." Journal of Nuclear Cardiology 23, no. 4 (June 25, 2015): 894–96. http://dx.doi.org/10.1007/s12350-015-0216-2.

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Kalantari, Forough, Nasibeh Mohseninia, Andreas Wetsch, Sara Harsini, Lukas Hehenwarter, Gregor Schweighofer-Zwink, Nazanin Zamani-Siahkali, Gundula Rendl, Mohsen Beheshti, and Christian Pirich. "Head-to-Head Comparison of CZT-SPECT and SPECT/CT Myocardial Perfusion Imaging: Interobserver and Intraobserver Agreement and Diagnostic Performance." Life 13, no. 9 (September 7, 2023): 1879. http://dx.doi.org/10.3390/life13091879.

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Background: Myocardial perfusion imaging (MPI) plays a crucial role in diagnosing coronary artery disease (CAD), with single-photon emission computed tomography (SPECT) being a widely accepted method. The accuracy of MPI relies on image quality and the expertise of physicians. While CZT-SPECT cameras offer advantages, they can be susceptible to attenuation artifacts. Therefore, our objective was to evaluate the diagnostic accuracy of CZT-SPECT and SPECT/CT in a clinical setting. Method: We conducted a prospective single-center study involving patients with known or suspected stable ischemic heart disease who underwent SPECT-MPI using CZT-SPECT and SPECT/CT scanners, and the latter was equipped with cardiofocal collimation. Experienced physicians performed analysis and reporting based on automated quantification and visual image interpretation. Results: A total of 77 patients (32 women (41.6%) and 45 men (58.4%) with an average age of 71.9 ± 8.9 years) were included. The agreement between readers regarding the final conclusion based on imaging reporting using both devices was very high (Kappa 0.87–0.93). Per-vessel analysis revealed a trend suggesting that CZT-SPECT was superior to conventional SPECT/CT in terms of sensitivity, positive predictive value (PPV), negative predictive value (NPV), and accuracy, although the difference did not reach statistical significance. Conclusion: Our study demonstrated that CZT-SPECT imaging offers comparable diagnostic accuracy, improved patient comfort, and eliminates CT-induced radiation compared to SPECT/CT. These findings suggest that cardiac CZT-SPECT imaging has the potential to become a valuable imaging modality in clinical practice.

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Pinaquy, J. B., E. Rhiai, F. Debordeaux, H. Douard, T. Couffinhal, G. De Saint Trivier, P. Coste, and L. Bordenave. "Comparaison des flux myocardiques mesurés en SPECT sur caméra CZT aux résultats angiographiques." Médecine Nucléaire 45, no. 4 (July 2021): 185. http://dx.doi.org/10.1016/j.mednuc.2021.06.027.

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Oddstig, Jenny, Elin Martinsson, Jonas Jögi, Henrik Engblom, and Cecilia Hindorf. "Differences in attenuation pattern in myocardial SPECT between CZT and conventional gamma cameras." Journal of Nuclear Cardiology 26, no. 6 (May 23, 2018): 1984–91. http://dx.doi.org/10.1007/s12350-018-1296-6.

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Larsson, S. A., G. Bergstrand, H. Bergstedt, J. Berg, O. Flygare, P.-O. Schnell, N. Andersson, and C. Lagergren. "A SPECIAL CUT-OFF GAMMA CAMERA FOR HIGH-RESOLUTION SPECT OF THE HEAD." Journal of Computer Assisted Tomography 9, no. 3 (May 1985): 645. http://dx.doi.org/10.1097/00004728-198505000-00099.

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Esnault, M., D. Legallois, P. Richard, D. Agostini, and A. Manrique. "Évaluation des artefacts et des faux positifs de la TEMP myocardique sur caméra CZT D-SPECT." Médecine Nucléaire 47, no. 2 (March 2023): 53. http://dx.doi.org/10.1016/j.mednuc.2023.01.028.

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Błaszczyk, Michał, Zbigniew Adamczewski, and Anna Płachcińska. "Capabilities of Modern Semiconductor Gamma Cameras in Radionuclide Diagnosis of Coronary Artery Disease." Diagnostics 11, no. 11 (November 17, 2021): 2130. http://dx.doi.org/10.3390/diagnostics11112130.

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This paper presents a review of the literature concerning the clinical application of modern semiconductor (CZT) gamma cameras in the radioinuclide diagnosis of coronary artery disease. It contains information on the diagnostic efficacy of myocardial perfusion studies performed with those cameras compared with the widely used scintillation (Anger) cameras, an overview of their effectiveness in comparison with coronary angiography (also fractional flow reserve) and currently available clinical results of a myocardial flow reserve measured with a dynamic SPECT study. Introduction of this imaging modality to the measurement of a myocardial flow reserve aims to facilitate access to this type of study compared to the less available and more expensive PET method used so far.

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Tossici-Bolt, Livia, John C. Dickson, Terez Sera, Robin de Nijs, Maria Claudia Bagnara, Catherine Jonsson, Egon Scheepers, et al. "Calibration of gamma camera systems for a multicentre European 123I-FP-CIT SPECT normal database." European Journal of Nuclear Medicine and Molecular Imaging 38, no. 8 (April 6, 2011): 1529–40. http://dx.doi.org/10.1007/s00259-011-1801-5.

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Blaire, Tanguy, Alban Bailliez, Fayçal Ben Bouallegue, Dimitri Bellevre, Denis Agostini, and Alain Manrique. "First assessment of simultaneous dual isotope (123I/99mTc) cardiac SPECT on two different CZT cameras: A phantom study." Journal of Nuclear Cardiology 25, no. 5 (March 8, 2017): 1692–704. http://dx.doi.org/10.1007/s12350-017-0841-z.

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Bordonne, Manon, Mohammad B. Chawki, Pierre-Yves Marie, Timothée Zaragori, Véronique Roch, Rachel Grignon, Laetitia Imbert, and Antoine Verger. "High-quality brain perfusion SPECT images may be achieved with a high-speed recording using 360° CZT camera." EJNMMI Physics 7, no. 1 (November 4, 2020). http://dx.doi.org/10.1186/s40658-020-00334-7.

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Abstract Objective The aim of this study was to compare brain perfusion SPECT obtained from a 360° CZT and a conventional Anger camera. Methods The 360° CZT camera utilizing a brain configuration, with 12 detectors surrounding the head, was compared to a 2-head Anger camera for count sensitivity and image quality on 30-min SPECT recordings from a brain phantom and from 99mTc-HMPAO brain perfusion in 2 groups of 21 patients investigated with the CZT and Anger cameras, respectively. Image reconstruction was adjusted according to image contrast for each camera. Results The CZT camera provided more than 2-fold increase in count sensitivity, as compared with the Anger camera, as well as (1) lower sharpness indexes, giving evidence of higher spatial resolution, for both peripheral/central brain structures, with respective median values of 5.2%/3.7% versus 2.4%/1.9% for CZT and Anger camera respectively in patients (p < 0.01), and 8.0%/6.9% versus 6.2%/3.7% on phantom; and (2) higher gray/white matter contrast on peripheral/central structures, with respective ratio median values of 1.56/1.35 versus 1.11/1.20 for CZT and Anger camera respectively in patients (p < 0.05), and 2.57/2.17 versus 1.40/1.12 on phantom; and (3) no change in noise level. Image quality, scored visually by experienced physicians, was also significantly higher on CZT than on the Anger camera (+ 80%, p < 0.01), and all these results were unchanged on the CZT images obtained with only a 15 min recording time. Conclusion The 360° CZT camera provides brain perfusion images of much higher quality than a conventional Anger camera, even with high-speed recordings, thus demonstrating the potential for repositioning brain perfusion SPECT to the forefront of brain imaging.

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Thiele, Felix, Franziska Schau, Julian M. M. Rogasch, Christoph Wetz, Stephanie Bluemel, Winfried Brenner, Holger Amthauer, Catharina Lange, and Imke Schatka. "Same same but different: dopamine transporter SPECT on scanners with CZT vs. NaI detectors." EJNMMI Research 13, no. 1 (March 22, 2023). http://dx.doi.org/10.1186/s13550-023-00973-8.

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Abstract Background The aims of this study were to establish a normal database (NDB) for semiquantification of dopamine transporter (DAT) single-photon emission computed tomography (SPECT) with [123I]FP-CIT on a cadmium zinc telluride (CZT) camera, test the preexisting NaI-derived NDB for use in CZT scans, and compare the diagnostic findings in subjects imaged with a CZT scanner with either the preexisting NaI-based NDB or our newly defined CZT NDB. Methods The sample comprised 73 subjects with clinically uncertain parkinsonian syndrome (PS) who prospectively underwent [123I]FP-CIT SPECT on a CZT camera according to standard guidelines with identical acquisition and reconstruction protocols (DaTQUANT). Two experienced readers visually assessed the images and binarized the subjects into “non-neurodegenerative PS” and “neurodegenerative PS”. Twenty-five subjects from the “non-neurodegenerative PS” subgroup were randomly selected to establish a CZT NDB. The remaining 48 subjects were defined as “test group”. DaTQUANT was used to determine the specific binding ratio (SBR). For the test group, SBR values were transformed to z-scores for the putamen utilizing both the CZT NDB and the manufacturer-provided NaI-based NDB (GE NDB). A predefined fixed cut-off of -2 was used for dichotomization of z-scores to classify neurodegenerative and non-neurodegenerative PS. Performance of semiquantification using the two NDB to identify subjects with neurodegenerative PS was assessed in comparison with the visual rating. Furthermore, a randomized head-to-head comparison of both detector systems was performed semiquantitatively in a subset of 32 out of all 73 subjects. Results Compared to the visual rating as reference, semiquantification based on the dedicated CZT NDB led to fewer discordant ratings than the GE NDB in CZT scans (3 vs. 8 out of 48 subjects). This can be attributed to the putaminal z-scores being consistently higher with the GE NDB on a CZT camera (median absolute difference of 1.68), suggesting an optimal cut-off of -0.5 for the GE NDB instead of -2.0. Average binding ratios and z-scores were significantly lower in CZT compared to NaI data. Conclusions Use of a dedicated, CZT-derived NDB is recommended in [123I]FP-CIT SPECT with a CZT camera since it improves agreement between semiquantification and visual assessment.

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Aguade-Bruix, S., A. Cardozo-Saavedra, A. Palomar Munoz, E. Aguirre, G. Romero-Farina, H. Cuellar-Calabria, M. N. Pizzi, and A. Roque. "Improvement of myocardial perfusion SPECT studies with a cardio-dedicated CZT gamma camera. Comparison with an analogical SPECT/CT gamma camera." European Heart Journal - Cardiovascular Imaging 25, Supplement_1 (June 27, 2024). http://dx.doi.org/10.1093/ehjci/jeae142.055.

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Abstract Aim To show the improvement in myocardial perfusion SPECT studies achieved in the year 2023 using a cardio-dedicated CZT gamma camera, compared to year 2021 when using an analogical SPECT/CT gamma camera. Methods We have collected data on nuclear cardiology care activity for the years 2021, 2022 and 2023, including patients treated in our institution. In 2021 myocardial perfusion imaging (MPI) studies were performed primarily on an analogical SPECT/CT gamma camera, which was replaced by a cardio-dedicated CZT in 2022. In 2023 MPI was carried out mainly in the new CZT gamma camera. For comparison we have selected the SPECT MPI studies performed in 2021 (one day protocol mainly with 18 + 12 minutes acquisition plus 10 minutes for in-out patient), and 2023 MPI studies (one day protocol mainly with 6 + 4 minutes acquisition plus 10 minutes for in-out patient). Results (Results Table) With the new CZT cardio-dedicated gamma camera, the number of stress SPECT increased by 442 (31%) and rest SPECT by 341 (23%), with a total annual increase of 783 SPECT studies (27%) in 2023 compared to 2021. Furthermore, the complexity of SPECT studies has increased in 2023, since part of the studies carried out (68) correspond to SPECT studies of myocardial blood flow, which are obtained in the same gamma camera simultaneously. In addition, the gamma camera acquisition time has reduced by 66% (from 30 to 10 minutes), and the patient total time has reduced by half (from 40 to 20 minutes). Counts in the cardiac area have increased on average more than 1000 times (14 million counts for a low dose study and 32 million for a high dose study). Conclusions The improvement achieved in SPECT studies for myocardial perfusion after upgrading to a cardio-dedicated CZT gamma camera has been an annual increase of 27% in number of SPECT studies, and a decrease in patient total time by half, which has allowed implementing more complex studies, such as evaluation of myocardial blood flow.

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Hesse, Michel, Florian Dupont, Nizar Mourad, Pavel Babczenko, Gwen Beaurin, Daela Xhema, Eliano Bonaccorsi-Riani, François Jamar, and Renaud Lhommel. "Kidney dynamic SPECT acquisition on a CZT swiveling-detector ring camera: an in vivo pilot study." BMC Medical Imaging 24, no. 1 (April 22, 2024). http://dx.doi.org/10.1186/s12880-024-01271-y.

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Abstract Background Large field of view CZT SPECT cameras with a ring geometry are available for some years now. Thanks to their good sensitivity and high temporal resolution, general dynamic SPECT imaging may be performed more easily, without resorting to dedicated systems. To evaluate the dynamic SPECT imaging by such cameras, we have performed an in vivo pilot study to analyze the kidney function of a pig and compare the results to standard dynamic planar imaging by a conventional gamma camera. Methods A 7-week-old (12 kg) female Landrace pig was injected with [99mTc]Tc-MAG3 and a 30 min dynamic SPECT acquisition of the kidneys was performed on a CZT ring camera. A fast SPECT/CT was acquired with the same camera immediately after the dynamic SPECT, without moving the pig, and used for attenuation correction and drawing regions of interest. The next day the same pig underwent a dynamic planar imaging of the kidneys by a conventional 2-head gamma camera. The dynamic SPECT acquisition was reconstructed using a MLEM algorithm with up to 20 iterations, with and without attenuation correction. Time-activity curves of the total counts of each kidney were extracted from 2D and 3D dynamic images. An adapted 2-compartment model was derived to fit the data points and extract physiological parameters. Comparison of these parameters was performed between the different reconstructions and acquisitions. Results Time-activity curves were nicely fitted with the 2-compartment model taking into account the anesthesia and bladder filling. Kidney physiological parameters were found in agreement with literature values. Good agreement of these parameters was obtained for the right kidney between dynamic SPECT and planar imaging. Regional analysis of the kidneys can be performed in the case of the dynamic SPECT imaging and provided good agreement with the whole kidney results. Conclusions Dynamic SPECT imaging is feasible with CZT swiveling-detector ring cameras and provides results in agreement with dynamic planar imaging by conventional gamma cameras. Regional analysis of organs uptake and clearance becomes possible. Further studies are required regarding the optimization of acquisition and reconstruction parameters to improve image quality and enable absolute quantification.

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Doyen, Matthieu, Gabriela Hossu, Sébastien Heyer, Timothée Zaragori, Laetitia Imbert, and Antoine Verger. "Identification of resting-state networks using dynamic brain perfusion SPECT imaging: A fSPECT case report." Frontiers in Human Neuroscience 17 (April 20, 2023). http://dx.doi.org/10.3389/fnhum.2023.1125765.

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Connectivity studies with nuclear medicine systems are scarce in literature. They mainly employ PET imaging and group level analyses due to the low temporal resolution of PET and especially SPECT imaging. Our current study analyses connectivity at an individual level using dynamic SPECT imaging, which has been enabled by the improved temporal resolution performances provided by the 360°CZT cameras. We present the case of an 80-year-old man referred for brain perfusion SPECT imaging for cognitive disorders for whom a dynamic SPECT acquisition was performed utilizing a 360°CZT camera (temporal sampling of 15 frames × 3 s, 10 frames × 15 s, 14 frames × 30 s), followed by a conventional static acquisition of 15 m. Functional SPECT connectivity (fSPECT) was assessed through a seed correlation analysis and 5 well-known resting-state networks were identified: the executive, the default mode, the sensory motor, the salience, and the visual networks. This case report supports the feasibility of fSPECT imaging to identify well known resting-state networks, thanks to the novel properties of a 360°CZT camera, and opens the way to the development of more dedicated functional connectivity studies using brain perfusion SPECT imaging.