CARDIAC ECHO-PLANAR MR-IMAGING - COMPARISON OF SINGLE-SHOT AND MULTIPLE-SHOT TECHNIQUES

PURPOSE: To compare the quality of cardiac images acquired with two- a nd four-shot echo-planar imaging (EPI) with that of images acquired wi th single-shot EPI. MATERIALS AND METHODS: Single-, two-, and four-sho t EPI was performed to obtain axial images that traversed both cardiac ventricles. The subjects were 10 healthy men whose ages ranged from 2 2 to 38 years (mean, 27 years). The multiple-shot EPI data were acquir ed in snapshot (sequential) and cardiac-gated (nonsequential) modes. I mage quality was compared by evaluation of the depiction of cardiac st ructures and analysis of signal intensity, contrast, and signal homoge neity. RESULTS: Multiple-shot EPI depicted the coronary and internal m ammary arteries better than did single-shot EPI (P < .05). Intraventri cular signal intensity was more homogeneous on multiple-shot images (P < .005). Cardiac-gated acquisition resulted in less image blurring an d allowed acquisition of more phases per RR interval. CONCLUSION: Mult iple-shot EPI rendered higher quality images than did single-shot EPI.