Probing chemical exchange using quantitative spin-lock R_1ρ asymmetry imaging with adiabatic RF pulses.

ABSTRACT:

Purpose

CEST is commonly used to probe the effects of chemical exchange. Although R_1ρ asymmetry quantification has also been described as a promising option for detecting the effects of chemical exchanges, the existing acquisition approaches are highly susceptible to B₁ RF and B₀ field inhomogeneities. To address this problem, we report a new R_1ρ asymmetry imaging approach, AC-iTIP, which is based on the previously reported techniques of irradiation with toggling inversion preparation (iTIP) and adiabatic continuous wave constant amplitude spin-lock RF pulses (ACCSL). We also derived the optimal spin-lock RF pulse B₁ amplitude that yielded the greatest R_1ρ asymmetry.

Methods

Bloch-McConnell simulations were us

SUBMITTER: Jiang B 

PROVIDER: S-EPMC6993944 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature