A Comparison of Half-Time vs Full-Time Myocardial SPECT Acquisitions using Flash 3D Reconstruction Software
Objective: This study was designed to determine if the Acquisition time for a low dose Sestamibi Myocardial scans (Dose = 3.7 MBq/Kg) could be halved while maintaining image quality by using Flash 3D reconstruction.
Method: A retrospective review was done and patients were selected for this study if they had normal Stress scan. In total 21 scans were selected with an acquisition time of 8mins and 24 scans with an acquisition time of 16 mins. All scans were processed using Siemens Flash 3D reconstruction. The rest component of the Myocardial Perfusion Scan was assessed by 3 experienced reporters and scored using a 20 segment bullseye. The scans were presented with the pagephase LUT and scored according to the colour indicating count density: Red and White = 0, Yellow and Orange = 1, Green = 2 and Blue and Black = 3. An unpaired t-test was used to analyse the data.
Results: Mean scores for reporter 1 were; Half-Time-3.8 (SD:2.3), Full-Time 3.5 (SD:3.9), which was not statistically significant (p=0.7226). Mean scores for reporter 2 were ;Half-Time 3.1 (SD:1.2), Full-time 1.8 (SD:1.2), which was a significant difference (p=0.0009). Mean scores for reporter 3 were; Half-Time 1.4 (SD: 0.2), Full-Time 0.9 (SD: 0.3), which was not a significant difference (p=0.2802).
Conclusion: A low dose 8-minute SPECT acquisition is inferior to a 16-minute acquisition if Flash 3D is used to process both. All reporters consistently scored the Full-Time scans better than the Half-Time scans though this was only statistically significant for reporter 2.