Improved delayed enhanced myocardial imaging with T₂‐Prep inversion recovery magnetization preparation

PURPOSE: To develop a magnetization preparation method that improves the differentiation of enhancing subendocardial infarction (MI) from ventricular blood for myocardial delayed-enhancement (DE) magnetic resonance imaging (MRI). MATERIALS AND METHODS: T2Prep-IR is a magnetization preparation pulse that consists of a T2 preparation (T2Prep) followed immediately by a nonselective inversion recovery (IR) pulse. The first imaging excitation is then delayed an inversion time (TI) to allow nulling of normal myocardium in DE study. The amount of T2 contrast is determined by the effective echo time of the T2Prep pulse, TEeff. TEeff is selected to differentiate MI and blood that share similar T1 values but have different T2 values. The T2Prep-IR preparation was incorporated into a fast gradient echo sequence to produce an image with both T1 and T2 weighting. Simulations predict that this method will generate improved contrast between MI and chamber blood compared to conventional IR methods. RESULTS: Comparisons between images acquired using conventional IR and T2Prep-IR in patients with MI indicate that this new approach significantly improves the blood-MI contrast (122+/-32% higher than that of IR with P<0.05). CONCLUSION: Our preliminary patient studies confirm that this preparation is helpful for improved delineation of subendocardial infarction.