Quasi-steady-state CEST (QUASS CEST) solution improves the accuracy of CEST quantification: QUASS CEST MRI-based omega plot analysis.

ABSTRACT:

Purpose

CEST MRI omega plot quantifies the labile proton fraction ratio (f_r ) and exchange rate (k_sw ), yet it assumes long RF saturation time (Ts) and relaxation delay (Td). Our study aimed to test if a quasi-steady-state (QUASS) CEST analysis that accounts for the effect of finite Ts and Td could improve the accuracy of CEST MRI quantification.

Methods

We modeled the MRI signal evolution using a typical CEST EPI sequence. The signal relaxes toward its thermal equilibrium following the bulk water relaxation rate during Td, and then toward its CEST steady state following the spin-lock relaxation rate during Ts from which the QUASS CEST effect is derived. Both f_r and k_sw were solved from simulated conventional apparent CEST and QUAS

SUBMITTER: Sun PZ 

PROVIDER: S-EPMC8076066 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature