NOVIFAST: A fast algorithm for accurate and precise VFA MRI $T_{1}$ mapping

In quantitative magnetic resonance T 1 mapping, the Variable Flip Angle (VFA) steady state spoiled gradient recalled echo (SPGR) imaging technique is popular as it provides a series of high resolution T 1 weighted images in a clinically feasible time. Fast, linear methods that estimate T 1 maps from these weighted images have been proposed, such as DESPOT1 and iterative re- weighted linear least squares (IRWLLS). More accurate, non- linear least squares (NLLS) estimators are in play, but these are generally much slower and require careful initialization. In this work, we present NOVIFAST, a novel NLLS-based algorithm specifically tailored to VFA SPGR T 1 mapping. By exploiting the particular structure of the SPGR model, a computationally efficient, yet accurate and precise T 1 map estimator is derived. Simulation and in vivo human brain experiments demonstrate a twenty-fold speed gain of NOVIFAST compared to conven- tional gradient-based NLLS estimators, while maintaining a high precision and accuracy. Moreover, NOVIFAST is eight times faster than efficient implementations of the VARPRO method. Furthermore, NOVIFAST is shown to be robust against initialization.

Jaar van publicatie:2018

Trefwoorden:A1 Journal article

BOF-keylabel:ja

BOF-publication weight:10

CSS-citation score:1

Auteurs:International

Authors from:Higher Education

Toegankelijkheid:Open