Diffusion magnetic resonance imaging detects an increase in interstitial fibrosis earlier than the decline of renal function
Lena Berchtold, Lindsey A. Crowe, Iris Friedli, David Legouis, Solange Moll, Thomas de Perrot, Pierre‐Yves Martin, Jean‐Paul Vallée, Sophie de Seigneux
Abstract
Interstitial fibrosis (IF) is one of the major predicting factors in chronic kidney disease, independently of estimated glomerular filtration rate (eGFR). IF can currently only be assessed by the examination of a kidney biopsy, an invasive examination that is difficult to perform repeatedly. Diffusion-weighted magnetic resonance imaging (MRI) is emerging as an important tool for non-invasive IF evaluation in native and transplant kidney. We recently adapted renal diffusion MRI with the application of a readout-segmented echo-planar sequence (RESOLVE), allowing for the discrimination between the cortical and medullary parts of the kidney and the calculation of the cortico-medullary apparent diffusion coefficient (ADC) difference (DADC). DADC was better correlated than absolute ADC to IF assessed by standard histology in both native kidney disease and transplant patients. Although a single time value of IF is clinically important, the follow-up of IF is sometimes even more relevant for clinical decisions and particularly important for the evaluation of the evolution of a disease.We have shown that our sequence was reproducible in healthy volunteers and patients but the use of diffusion MRI for the follow-up of IF of a given patient with the renal disease had not yet been evaluated. We thus aimed at analysing the use of diffusion MRI for the follow-up of IF in patients having undergone repeated biopsies and its value in comparison with renal function follow-up.