Chronic kidney disease (CKD) is a significant global health problem with fibrosis being a common pathway of disease progression. While MRI is sensitive to fibrosis, the relationship to ultrastructural underpinnings is not well understood. In this study, we evaluate an oxalate induced CKD model and determine the correlation of MRI metrics with high-resolution terminal endpoints. We find that FA and AD in the medulla are most correlated with fibrosis pathologies, new hydroxyproline, and inflammatory and fibrotic gene expression. These results show that MRI can detect fibrosis and that the signal change is related to interstitial fibrosis and nephron ultrastructure.