Improving the image quality of short-time bone SPECT using CZT detectors with SwiftScan

Abstract

Abstract Objective This study aimed to evaluate the quality and associated quantitative values of bone single-photon emission computed tomography (SPECT) with and without SwiftScan using a semiconductor camera equipped with a cadmium-zinc-telluride (CZT) detector.Methods Ten patients with bone metastases from prostate cancer who underwent list-mode SPECT/computed tomography using a whole-body semiconductor camera were included in this study. A total dose of 740 MBq was administered. Standard SPECT images were taken approximately 3 h later, and images were constructed with and without SwiftScan.Results A total of 130 metastatic lesions in 10 patients were analyzed. The dose injected was 732.8 (662.3-878.1) MBq, and the time to start the test after injection was 200.5 (165།220) min. The intraclass correlation coefficient (ICC) was 0.952 at 5% for the standard time without SwiftScan and 0.990 with SwiftScan. The percentage of maximum standardized uptake value (SUVmax) changes of > 10% without SwiftScan was 0.7% at 100% of the images in the list mode data, 4.6% at 75%, 16.9% at 50%, 28.5% at 25%, 56.2% at 10%, and 68.4% at 5%. In contrast, with SwiftScan, SUVmax changes of > 10% were associated with 0.75% at 75%, 3.85% at 50%, 20.8% at 25%, 30.8% at 10%, and 40.8% at 5%. The contrast-to-noise ratios (CNR) were 95.3 at 75%, 88.3 at 50%, 69.2 at 25%, 45.7 at 10%, and 31.6 at 5% without SwiftScan, and were 96.9, 91.7, 78.0, 71.6, and 62.0, respectively, with SwiftScan.Conclusion SwiftScan can produce reliable images even with ultrashort acquisition times, and improves image quality and associated quantitative values. The method reported herein can be used to reduce SPECT inspection time.