Gated myocardial perfusion SPECT: 180° versus 360° reconstruction

Introduction: The impact of 180° myocardial perfusion SPECT reconstruction on decreasing resolution may also impact on LV volume and LVEF. The purpose of this project was to determine the relationship between 180° and 360° gated myocardial perfusion SPECT reconstruction for the LV volumes and LVEF determined by QGS analysis and to determine whether QGS software is robust to variations in reconstruction parameters. Methodology: Each of 50 gated SPECT data sets (25 rest and 25 stress) were reconstructed using both 180° and 360° filtered backprojection simultaneously and quantified with automated QGS software to determine the LVEF, end diastolic volume (EDV) and end systolic volume (ESV). Results: The mean LVEF for 180° reconstruction was 49.5% and 49.7% for 360° reconstruction. No statistically significant difference was noted between matched pairs (P = 0.51). The mean EDV for 180° reconstruction was 108.3 ml and 104.6 ml for 360° reconstruction. A statistically significant difference was noted between matched pairs (P = 0.0006). The mean ESV for 180° reconstruction was 58.9 ml and 56.7 ml for 360° reconstruction. Again a statistically significant difference was noted between matched pairs (P = 0.0031). Conclusion: The QGS determined LVEF is robust to variations in reconstruction strategy. If 360° data is acquired, QGS software is capable of performing reliable reconstruction.