Accelerated T2-weighted imaging of water, fat and silicone with joint reconstruction and species separation.

Motivation: T2-weighted imaging of patients with breast silicone implants can be prolonged due to the need to encode multiple echoes for separating three chemical species, while obtaining sufficient T2-weighting and limiting T2*-blur. Goal(s): This work explores joint regularized reconstruction and species separation method to better exploit ky-TE undersampling in a multiecho acquisition. Approach: The joint formulation allows for temporal data coupling and compressed-sensing-like regularization on separated species. Results: The joint method improves water imaging compared to the two-stage approach, and retrospective undersampling experiments show combining it with incoherent ky-TE sampling allows for higher acquisition accelerations. Impact: WFS-separated T2-weighted imaging with multi-gradient-echo acquisition can be accelerated ~1.5x by solving jointly for parallel imaging and species separation and incoherently undersampling in the ky-TE domain.