Simultaneous pH-sensitive and oxygen-sensitive MRI of human gliomas at 3 T using multi-echo amine proton chemical exchange saturation transfer spin-and-gradient echo echo-planar imaging (CEST-SAGE-EPI).

ABSTRACT:

Purpose

To introduce a new pH-sensitive and oxygen-sensitive MRI technique using amine proton CEST echo spin-and-gradient echo (SAGE) EPI (CEST-SAGE-EPI).

Methods

pH-weighting was obtained using CEST estimations of magnetization transfer ratio asymmetry (MTR_asym ) at 3 ppm, and oxygen-weighting was obtained using R2' measurements. Glutamine concentration, pH, and relaxation rates were varied in phantoms to validate simulations and estimate relaxation rates. The values of MTR_asym and R2' in normal-appearing white matter, T₂ hyperintensity, contrast enhancement, and macroscopic necrosis were measured in 47 gliomas.

Results

Simulation and phantom results confirmed an increase in MTR_asym with decreasing pH. The CEST-SAGE-EPI est

SUBMITTER: Harris RJ 

PROVIDER: S-EPMC6107417 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature