Non-Linear Echo Combination Allows for Reduced Scan Times in T2* Weighted Imaging at 1.5T

Motivation: Scan times for multi-echo T2*w sequences are too long at 1.5T. Goal(s): Shorten scan times by reducing the number of echoes needed for a specific contrast. Approach: During this ISMRM, we introduced a novel echo combination method that increases contrast over the standard Root Sum-of-Squares (RSOS) technique. We applied this method to 7 and 6 echo 3D SPGR protocols and compared the results to a 9 echo protocol that used RSOS. Results: Contrast was comparable or better in the 6 and 7 echo protocols using our technique, compared to the 9 echo protocol with RSOS, resulting in a scan time reduction of 23-26%. Impact: Our echo combination technique allows fewer echoes in multi-echo T2*w imaging to match the contrast of higher echo protocols resulting in a 23-26% scan time reduction. This alleviates one of the primary concerns clinicians have using T2*w imaging at 1.5T.