Abstract #3021

Nikolova S, Bartha R, Bowen C

The LASER pulse sequence is sensitive to diffusion of spins through regions with different microscopic susceptibility. The purpose of this study was to investigate the contribution of microscopic susceptibility to LASER signal intensity, and compare it to a conventional CPMG pulse sequence. ORGASOL polyamide powders were used to generate different magnetic susceptibility in three phantoms. Transverse relaxation rates R2 were measured in each phantom as a function of the spin echo refocusing time (2tcp) within LASER and CPMG pulse sequences. Differences between LASER and CPMG R2 were found in the low tcp range, demonstrating increased sensitivity to microscopic susceptibility in LASER.