Diffusional kurtosis imaging in assessing renal function and pathology of IgA nephropathy: a preliminary clinical study. Issue 9 (September 2018) - Liu, Y.
Abstract : Aim: To evaluate renal fibrosis in immunoglobulin A nephropathy (IgAN) using diffusion kurtosis imaging (DKI). Materials and methods: Twenty patients with biopsy-proven IgAN were enrolled. DKI was performed on a clinical 3 T magnetic resonance imaging (MRI) system, and region-of-interest measurements were conducted to determine mean kurtosis (K), mean diffusivity (D), and apparent diffusion coefficient (ADC) of the kidney cortex. Renal biopsy specimens were scored based on the severity of renal fibrosis. The associations between the DKI data and clinicopathological parameters were investigated. Results: Both the K and ADC were not only well correlated with the estimated glomerular filtration rate, but also significantly associated with the pathological scores of fibrosis, including the glomerular sclerosis index (K: r =0.759, p <0.001; ADC: r =−0.636, p =0.003) and the percentage of tubular atrophy and interstitial fibrosis (K: r =0.767, p <0.001; ADC: r =−0.702, p =0.001). Further receiver operating characteristic analysis showed that K demonstrated better diagnostic performance in discriminating severe glomerulosclerosis (area under curve [AUC] 0.970, sensitivity 81.8%, specificity 100%), and ADC displayed better capabilities in identifying severe tubular atrophy/interstitial fibrosis (AUC 0.976, sensitivity 100%, specificity 92.9%). Conclusion: This DKI method can be used to detect renal fibrosis in IgAN in a non-invasive manner and may provide additional information for characterisation and surveillance. Highlights: Diffusional kurtosis imaging could reveal the presence of non-Gaussian diffusion. Kurtosis were well correlated with renal function. Kurtosis were also significantly associated with the pathologic scores of fibrosis. Diffusional kurtosis imaging could be a noninvasive method to detect renal fibrosis.