PT - JOURNAL ARTICLE AU - Elkamhawy, Abdelhamid A. AU - Chandna, Harish TI - Minimum Detectable Defect Thickness in SPECT Myocardial Perfusion Test: Phantom Study with <sup>99m</sup>Tc and <sup>201</sup>Tl DP - 2001 Dec 01 TA - Journal of Nuclear Medicine Technology PG - 183--188 VI - 29 IP - 4 4099 - http://tech.snmjournals.org/content/29/4/183.short 4100 - http://tech.snmjournals.org/content/29/4/183.full SO - J. Nucl. Med. Technol.2001 Dec 01; 29 AB - Objective:The purpose of this study was to determine experimentally the minimum thickness (Dmin) of a defect inserted on the myocardial wall of a cardiac phantom at different locations that could be clearly detected in a SPECT perfusion study using 99mTc and 201Tl. Methods:Rectangular (or cylindrical) defects with the same thickness were inserted on the inner surface of a myocardial phantom at 5 different locations: anterior (ANT), septal (SEP), inferoposterior (IP), lateral (LAT), and apical (AP). For different defect thickness (from 1 to 7 mm, in increments of 1 mm) the myocardial SPECT perfusion study was performed with 99mTc and 201Tl using the same protocol that we use for patients. Baseline studies (with no defect inserted) were also performed. The SPECT images of the myocardial phantom with defects were compared with baseline SPECT images to determine whether the defect could be clearly identified. Results:The uniformity of the baseline SPECT images was analyzed very carefully where an IP artifact was detected. The Dmin was determined for 99mTc and 201Tl at 3 radii of rotation: 21.0, 25.0, and 29.2 cm. Conclusion:To be detected on SPECT images, a defect must be of a thickness ≥Dmin. A simple method for performing a quality control test for SPECT nuclear cardiology can be developed based on these findings.