[Effect of Parameters Related to Sampling Time on Resolution Characteristics of Fast TSE Dixon Method].

Abstract

Purpose: Fast turbo spin echo (TSE) Dixon method, which acquires both in-phase and opposed-phase in a single echo train, resulting in a 50% reduction in imaging times compared to the TSE Dixon method. However, it has been observed that the Fast TSE Dixon method exhibits degraded resolution characteristics when scanned under the same parameters as the TSE Dixon method. This study aimed to reveal suitable scan parameters for the Fast TSE Dixon method by examining its resolution characteristics when altering the parameter of the receiver bandwidth (BW) and asymmetric echoes related to sampling time.

Methods: The BW was adjusted to 400, 600, 800, and 1000 Hz/pixel for the TSE Dixon and Fast TSE Dixon methods. In addition, the parameter of asymmetric echoes was changed to on (weak), and off of the Fast TSE Dixon method. The modulation transfer function (MTF) of each sequence was assessed using the edge spread function in the frequency encoding direction and phase encoding direction.

Results: The findings indicated that the MTFs of the TSE Dixon method remained constant despite alterations in the sampling time. Conversely, the MTFs of the Fast TSE Dixon method showed that resolution characteristics improved by shortening sampling time when the BW was expanded, and the asymmetric echoes were changed to on.

Conclusion: We revealed suitable scan parameters for the Fast TSE Dixon method have been found to improve resolution characteristics by shortening sampling time when the BW was expanded and the asymmetric echoes were changed to on.