Die Zukunft der Nuklearmedizin ist digital – Grundlagen und klinische Vorteile von CZT-basierten Gammakameras

Zusammenfassung

Die Nuklearmedizin geht auf ihre technologischen Wurzeln bis in die 1950er-Jahre mit der Erfindung der Anger-Kamera zurück. Obwohl sich die Technik seitdem stetig weiterentwickelt hat, hat sich das zugrunde liegende Funktionsprinzip des Detektors in dieser Zeit nicht verändert und Grenzen im Bereich der Leistung von Gammakameras gesetzt. Mit dem Einsatz von Cadmium-Zink-Tellurid (CZT)-Detektoren mit direkter Konversionstechnologie werden diese traditionellen Grenzen überwunden. CZT-basierte Gammakameras können heute dank der geringen Abmessungen der pixelierten CZT-Detektormodule mit vollständig neuer und unkonventioneller Systemgeometrie entworfen werden. Im Vergleich zu den konventionellen Gammakameras haben CZT-basierte Gammakameras eine deutlich verbesserte Systemleistung, die sich im Wesentlichen aus räumlicher Auflösung, Energieauflösung, Sensitivität und Totzeit zusammensetzt. Diese verbesserten Eigenschaften erhöhen den Patientenkomfort und die diagnostische Konfidenz. Durch kürzere Untersuchungszeiten und/oder eingesparte Dosis können Arbeitsabläufe optimiert werden und neue Untersuchungen wie die simultane duale Isotopenuntersuchung oder die Bestimmung des myokardialen Blutflusses und der koronaren Flussreserve durchgeführt werden.

Abstract

With the invention of the Anger camera nuclear medicine dates to its technological roots in the 1950s. Although technology was continuously improving, the basic function of the gamma detector never changed which sets the boundaries of its current performance. These obstacles were overcome with the implementation of Cadmium-Zinc-Telluride (CZT) detectors with direct conversion. Today, thanks to small dimensions of the pixelated CZT detector modules, CZT-based gamma cameras can be designed with completely new and unconventional geometry. Compared to conventional gamma cameras, CZT has a clearly improved overall system performance in terms of spatial and energy resolution, sensitivity and dead time. These improved features increase patient comfort and satisfaction as well as diagnostic confidence. Shorter scan times and/or reduced dose help improve clinical workflows and enable new studies like simultaneous dual isotope examination or the determination of myocardial blood flow and coronary flow reserve.

Schlüsselwörter

CZT-Detektor - direkte Konversionstechnologie - dedizierte Herzkamera - CZT-basierte Großfeldgammakamera - Dosisreduktion - simultane duale Isotopendetektion

Keywords

CZT detector - direct conversion - dedicated cardiac gamma camera - CZT-based general purpose gamma camera - dose reduction - simultaneous dual-isotope imaging

• Literatur

• 1 Knoll GF. Radiation detection and measurement. 4th. Aufl. Hoboken, N.J.: Wiley; 2010
• 2 Iwanczyk JS, Iniewski K. Radiation detectors for medical imaging. Portland: Taylor & Francis Inc; 2015
• 3 Ben-Haim S, Kennedy J, Keidar Z. Novel Cadmium Zinc Telluride Devices for Myocardial Perfusion Imaging-Technological Aspects and Clinical Applications. Semin Nucl Med 2016; 46: 273-285
• 4 Bocher M, Blevis IM, Tsukerman L. et al. A fast cardiac gamma camera with dynamic SPECT capabilities: design, system validation and future potential. Eur J Nucl Med Mol Imaging 2010; 37: 1887-190
• 5 Beekman F, van der Have F. The pinhole: gateway to ultra-high-resolution three-dimensional radionuclide imaging. Eur J Nucl Med Mol Imaging 2007; 34: 151-161
• 6 Sharir T, Pinskiy M, Pardes A. et al. 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. J Nucl Cardiol 2016; 23: 11-20
• 7 Einstein AJ, Johnson LL, DeLuca AJ. et al. Radiation dose and prognosis of ultra-low-dose stress-first myocardial perfusion SPECT in patients with chest pain using a high-efficiency camera. J Nucl Med 2015; 56: 545-551
• 8 Imbert L, Poussier S, Franken PR. et al. Compared performance of high-sensitivity cameras dedicated to myocardial perfusion SPECT: a comprehensive analysis of phantom and human images. J Nucl Med 2012; 53: 1897-1903
• 9 Nkoulou R, Fuchs T, Pazhenkottil AP. et al. High efficiency gamma camera enables ultra-low fixed dose stress/rest myocardial perfusion imaging. European Heart Journal 2018; 0: 1-7
• 10 Bailliez A, Lairez O, Merlin C. et al. Left Ventricular Function Assessment Using 2 Different Cadmium-Zinc-Telluride Cameras Compared with a gamma-Camera with Cardiofocal Collimators: Dynamic Cardiac Phantom Study and Clinical Validation. J Nucl Med 2016; 57: 1370-1375
• 11 Duvall WL, Sweeny JM, Croft LB. et al. Reduced stress dose with rapid acquisition CZT SPECT MPI in a non-obese clinical population: comparison to coronary angiography. J Nucl Cardiol 2012; 19: 19-27
• 12 Nkoulou R, Fuchs T, Pazhenkottil AP. et al. High efficiency gamma camera enables ultra-low fixed dose stress/rest myocardial perfusion imaging. Eur Heart J Cardiovasc Imaging 2019; 20: 218-224
• 13 Nkoulou R, Pazhenkottil AP, Kuest SM. et al. Semiconductor detectors allow low-dose-low-dose 1-day SPECT myocardial perfusion imaging. J Nucl Med 2011; 52: 1204-1209
• 14 Gimelli A, Pugliese NR, Kusch A. et al. Accuracy of cadmium-zinc-telluride imaging in detecting single and multivessel coronary artery disease: Is there any gender difference?. Int J Cardiol 2019; 274: 388-393
• 15 Zavadovsky KV, Mochula AV, Boshchenko AA. et al. Absolute myocardial blood flows derived by dynamic CZT scan vs invasive fractional flow reserve: Correlation and accuracy. J Nucl Cardiol 2019; DOI: 10.1007/s12350-019-01678-z.
• 16 Fang YD, Liu YC, Ho KC. et al. Single-scan rest/stress imaging with 99mTc-Sestamibi and cadmium zinc telluride-based SPECT for hyperemic flow quantification: A feasibility study evaluated with cardiac magnetic resonance imaging. PLoS One 2017; 12: e0183402
• 17 Iskandrian AE, Dilsizian V, Garcia EV. et al. Myocardial perfusion imaging: Lessons learned and work to be done-update. J Nucl Cardiol 2018; 25: 39-52
• 18 Bani SadrA, Testart N, Tylski P. et al. Reduced Scan Time in 123I-FP-CIT SPECT Imaging Using a Large-Field Cadmium-Zinc-Telluride Camera. Clin Nucl Med 2019; 44: 568-569
• 19 Gregoire B, Pina-Jomir G, Bani-Sadr A. et al. Four-Minute Bone SPECT Using Large-Field Cadmium-Zinc-Telluride Camera. Clin Nucl Med 2018; 43: 389-395
• 20 Caobelli F, Wollenweber T, Bavendiek U. et al. Simultaneous dual-isotope solid-state detector SPECT for improved tracking of white blood cells in suspected endocarditis. Eur Heart J 2017; 38: 436-443
• 21 Blaire T, Bailliez A, Ben Bouallegue F. et al. Determination of the Heart-to-Mediastinum Ratio of ¹²³I-MIBG Uptake Using Dual-Isotope (¹²³I-MIBG/^99mTc-Tetrofosmin) Multipinhole Cadmium-Zinc-Telluride SPECT in Patients with Heart Failure. J Nucl Med 2018; 59: 251-258
• 22 Yamada Y, Nakano S, Gatate Y. et al. Feasibility of simultaneous ^99mTc-tetrofosmin and ¹²³I-BMIPP dual-tracer imaging with cadmium-zinc-telluride detectors in patients undergoing primary coronary intervention for acute myocardial infarction. J Nucl Cardiol 2019; DOI: 10.1007/s12350-018-01585-9.