Gated tomographic radionuclide angiography using cadmium-zinc-telluride detector gamma camera; comparison to traditional gamma cameras

Purpose Estimation of left ventricular ejection fraction (LVEF) with equilibrium 99MTc-HSA equilibrium radionuclide angiography (MUGA) is frequently used for assessing cardiac function. The purpose of this study was to compare intra- and interobserver variation between three different gamma cameras. Materials and Methods Eighty-two patients, scanned in the same sequential order on the three cameras. Each acquisition was analyzed twice by two technologists. Inter- and intraobserver variations were calculated as the coefficient of variation and the 95% confidence interval for limits of agreement between each sequence of analyses for each of the three cameras. Results The lowest intraobserver variations in LVEF for the two NaI-detector cameras were 3.1% (−4.0% to 3.5%) for the planar and 3.4% (−4.2% to 4.5%) for SPECT ( P ≤ 0.001-0.019), the highest result for the CZT SPECT camera was 2.6% (−2.9% to 3.1%). Similarly, interobserver variation was 4.8% (−4.8% to 6.4%) and 4.9% (−5.4% to 7.5%), respectively, for each of the NaI-detector cameras and 3.3% (−3.4% to 4.3%) for the CZT SPECT camera ( P ≤ 0.001-0.008). Discussion The CZT detector camera was superior to both NaI detector cameras regarding intra- and interobserver variation. The CZT SPECT camera may identify changes in LVEF with greater certainty than its NaI detector-equipped counterparts.