PT - JOURNAL ARTICLE AU - Rene Nkoulou AU - Aju P. Pazhenkottil AU - Silke M. Kuest AU - Jelena R. Ghadri AU - Mathias Wolfrum AU - Lars Husmann AU - Michael Fiechter AU - Ronny R. Buechel AU - Bernhard A. Herzog AU - Pascal Koepfli AU - Cyrill Burger AU - Oliver Gaemperli AU - Philipp A. Kaufmann TI - Semiconductor Detectors Allow Low-Dose–Low-Dose 1-Day SPECT Myocardial Perfusion Imaging AID - 10.2967/jnumed.110.085415 DP - 2011 Aug 01 TA - Journal of Nuclear Medicine PG - 1204--1209 VI - 52 IP - 8 4099 - http://jnm.snmjournals.org/content/52/8/1204.short 4100 - http://jnm.snmjournals.org/content/52/8/1204.full SO - J Nucl Med2011 Aug 01; 52 AB - Cadmium zinc telluride (CZT) detectors with linear counting rate response enable count subtraction in sequential scanning. We evaluated whether count subtraction eliminated the need for higher activity doses in the second part of the 1-d stress–rest myocardial perfusion imaging (MPI) protocol. Methods: For 50 patients (mean age ± SD, 66 ± 12 y) with visually abnormal (n = 42) or equivocal (n = 8) adenosine-stress MPI (320 MBq of 99mTc-tetrofosmin) on a CZT camera, rest MPI was performed with a low dose (320 MBq) and repeated after injection of an additional 640 MBq of 99mTc-tetrofosmin to achieve a standard 3-fold increased dose at rest (960 MBq), compared with stress (320 MBq). Low-dose rest myocardial perfusion images were reconstructed after subtracting the background activity of the preceding stress scan. Segmental percentage tracer uptake of the 2 rest myocardial perfusion images (320 vs. 960 MBq) was compared using intraclass correlation and Bland–Altman limits of agreement. Patient- and coronary territory–based clinical agreement was assessed. Results: The standard protocol revealed ischemia in 34 (68%) and a fixed defect in 8 (16%) patients, of whom 33 (97%) and 8 (100%) were correctly identified by low-dose MPI (clinical agreement, 98%). Segmental uptake correlated well between low- and standard-dose rest scans (r = 0.94, P < 0.001; Bland–Altman limits of agreement, −11 to +11%). Defect extent was 14.4% (low-dose) versus 13.1% (standard-dose) at rest (P = not statistically significant) and 26.6% at stress (P < 0.001 vs. rest scans). Conclusion: These promising results suggest that accurate assessment of ischemic myocardial disease is feasible with a low-dose–low-dose 1-d SPECT MPI protocol using a CZT device.