Objectives: To evaluate the function of kidneys with renal artery stenosis using multiparametric magnetic resonance imaging, assess the diagnostic efficacy of multiparametric magnetic resonance imaging for single kidney dysfunction.
Materials and methods: Renal multiparametric magnetic resonance imaging was performed on 62 patients with RAS using the Philips Ingenia CX 3.0 T MRI machine. The scanning sequences included arterial spin labeling, phase contrast MRI, diffusion weighted imaging, T1 mapping, and blood oxygen level-dependent MRI. All patients underwent radionuclide renal dynamic imaging, and the glomerular filtration rate (GFR) was calculated to determine renal function. Individual kidneys from renal artery stenosis patients were classified into normal (GFR ≥ 30) and reduced (GFR < 30) groups and the ability of the uni- and multi-variate logistic regression model to predict the group was determined.
Results: MR parameters demonstrated considerable diagnostic efficacy for single kidney dysfunction, with AUC range of 0.597- 0.864. The strongest predictor was mean renal artery blood flow. The sensitivity and specificity were 0.93 and 0.69AUC was 0.864. The strongest predictors of the renal microstructure were cortical apparent diffusion coeffecient and T1 value, with ROC AUCs of 0.756 and 0.741, sensitivities of 0.875 and 0.689, and specificities of 0.537 and 0.731. Multiparametric MRI combined with the values of cortical renal blood flow and cortical T1 exhibited the highest diagnostic efficacy, with an AUC of 0.92, and sensitivity of 0.919, and specificity of 0.743.
Conclusion: Multiparametric magnetic resonance imaging can effectively detect the single renal dysfunction of kidneys with renal artery stenosis, which holds promise for the diagnosis and prognosis of patients with renal artery stenosis.
Keywords: Multiparametric magnetic resonance imaging; glomerular filtration rate; kidney function; renal artery stenosis.
Multiple MR parameters demonstrated good predictive ability for single kidney function impairment.The combined application of multiparametric MRI indicators enhance the diagnostic efficacy of renal function impairment in renal artery stenosis.The renal cortical RBF combining the cortical T1 value exhibited the highest diagnostic efficacy for renal function impairment.