Utility of multislice computed tomography with a 64-data acquisition system for four-dimensional volumetric analysis using a pulsating phantom and considering pulsation rate and reconstruction methods.

Purpose: To evaluate 64-data acquisition system (DAS) MSCT (Light Speed VCT, GE) at 0.625 mm slice thickness, 0.35 s/rotation, tube 120 kV at 400 mA, ECG-gated for 4-D volumetric analysis, we used pulsating phantoms to measure end-diastolic (EDV) and end-systolic (ESV) volume and ejection fraction (EF) to assess reconstruction methods especially for higher pulsation rates.

Materials And Methods: A pulsating device (AZ-631N, Anzai Medical) with contrast material (300 mgI/dl) diluted 10x with saline was moved at 40-110 to-and-fro movements/min. ECG-gated MSCT was performed x5 per pulsation rate. The EDV and ESV were measured using workstation (Virtual Place Advance Plus, Aze).

Results: The mean EDV and ESV were 98, 97, 97 96, 95, 94, and 101% and 145, 143, 142, 144, 145, 149, 156 and 160%, respectively, compared to the static state. EF was 80, 81, 81, 80, 79, 77, 73, and 76% at 40-110 pulsations/min, when reconstructed by the segmented method, but was improved to 82, 83, 85, and 84% at 80-110 beat/min when reconstructed by the burst method. The latter is therefore more appropriate for higher rates.

Conclusion: This 64-DAS MSCT can measure EDV even at high beat rates (up to 110 beats per minute) compared to the static state. Because ESV tended to be overestimated by approximately 140-160% compared with the static state, EF tended to be underestimated by approximately 73-81% compared with the static state. However, at higher beat rates of >70 beat/min, an appropriate reconstruction method (the burst method) may further improve the accuracy of EF measurement.