Multi-echo bipolar pulse sequences are becoming increasingly popular in structural brain imaging applications that require high SNR efficiency and minimal geometrical distortions or water-fat shifts. However, various discrepant expressions for the SNR as a function of T2* and the sampling bandwidth were previously reported, making it unclear as to how multiple bipolar echoes should be combined to maximize SNR. In this study, we compare some traditional single-echo (low-bandwidth) FLASH and MPRAGE sequences with their multi-echo bipolar (high bandwidth) counterparts and validate the SNR theory via phantom measurements. Bipolar MPRAGE/FLASH yield SNR gains of ~1.3/1.6-fold, in good agreement with the theory.
This abstract and the presentation materials are available to members only; a login is required.