Dynamic assessment of renal function by using endogenous CEST MRI in a reversible unilateral ureter obstruction rat model

Motivation: Reversal of ureter obstruction can prevent renal fibrosis outcome. Goal(s): In this study, we employed endogenous chemical exchange saturation transfer(CEST) MRI technique to assess dynamic renal function changes in reversible unilateral ureter obstruction (RUUO) rat model. Approach: The CEST effect changes of multiple protons at different B1 strengths (1 and 2μT) were analyzed. Results: Our results showed CEST MRI could demonstrate the progress and relief of obstructive nephropathy. The hydroxyl was the most sensitive proton before and after relief of ureter obstruction, while the amide changed slowly after relief at 1μT strength in renal cortex and outer medulla. Impact: Endogenous CEST MRI could serve as a potential biomaker to evaluate the early renal fibrosis process induced by reversible unilateral ureter obstruction (RUUO). Different patterns of CEST effects in multiple protons possibly reflect various potential metabolic mechanisms.