A comparison of exogenous and endogenous CEST MRI methods for evaluating in vivo pH.

ABSTRACT:

Purpose

Extracellular pH (pHe) is an important biomarker for cancer cell metabolism. Acido-chemical exchange saturation transfer (CEST) MRI uses the contrast agent iopamidol to create spatial maps of pHe. Measurements of amide proton transfer exchange rates (k_ex ) from endogenous CEST MRI were compared to pHe measurements by exogenous acido-CEST MRI to determine whether endogenous k_ex could be used as a proxy for pHe measurements.

Methods

Spatial maps of pHe and k_ex were obtained using exogenous acidoCEST MRI and an endogenous CEST MRI analyzed with the omega plot method, respectively, to evaluate mouse kidney, a flank tumor model, and a spontaneous lung tumor model. The pHe and k_ex results were evaluated using pixelwise comparison

SUBMITTER: Lindeman LR 

PROVIDER: S-EPMC5821269 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature