Real-Time Volumetric Imaging of Human Heart Without Electrocardiographic Gating by 256-Detector Row Computed Tomography: Initial Experience

Objective: The feasibility of human cardiac imaging using a prototype 256-detector row cone-beam computed tomography (256CBCT) scanner without electrocardiographic gating was examined. Methods: Two healthy male volunteers were examined by contrast-enhanced 256CBCT. The number of detectors was 912 × 256, each measuring approximately 0.5 mm × 0.5 mm at the center of rotation. The craniocaudal coverage was approximately 100 mm after reconstruction by the Feldkamp-Davis-Kress algorithm. The effective time resolution was 500 milliseconds using a half-scan algorithm. Results: Serial enhancement of the left ventricular myocardium was detected. The right and left coronary arteries at proximal and distal segments were depicted without significant blurring. Although the left ventricular wall motion on cine images was not smooth over time, it was possible to measure ventricular volume and ejection fraction. Conclusions: Using the 256CBCT, it was possible to visualize the coronary arteries, myocardial perfusion, and ventricular contraction simultaneously during a single acquisition.