Multiparametric Renal Magnetic Resonance Imaging: Validation, Interventions, and Alterations in Chronic Kidney Disease

作者：Cox Eleanor F; Buchanan Charlotte E; Bradley Christopher; Prestwich Benjamin; Mahmoud Huda; Taai Maarten; Selby Nicholas M; Francis Susan T

来源：Frontiers in Physiology, 2017, 8: 696.

DOI：10.3389/fphys.2017.00696

• magnetic resonance imaging
• hemodynamics
• oxygenation
• renal function
• arterial spin labeling

Background: This paper outlines a multiparametric renal MRI acquisition and analysis protocol to allow non-invasive assessment of hemodynamics (renal artery blood flow and perfusion), oxygenation (BOLD T-2 *), and microstructure (diffusion, T-1 mapping).
Methods: We use our multiparametric renalMRI protocol to provide (1) a comprehensive set of MRI parameters [ renal artery and vein blood flow, perfusion, T-1, T-2 *, diffusion (ADC, D, D*, f(p)), and total kidney volume] in a large cohort of healthy participants (127 participants with mean age of 41 +/- 19 years) and show the MR field strength (1.5 T vs. 3 T) dependence of T-1 and T-2* relaxation times; (2) the repeatability ofmultiparametric MRI measures in 11 healthy participants; (3) changes in MRI measures in response to hypercapnic and hyperoxic modulations in six healthy participants; and (4) pilot data showing the application of the multiparametric protocol in 11 patients with Chronic Kidney Disease (CKD).
Results: Baseline measures were in-line with literature values, and as expected, T-1-values were longer at 3 T compared with 1.5 T, with increased T-1 corticomedullary differentiation at 3 T. Conversely, T-2* was longer at 1.5 T. Inter-scan coefficients of variation (CoVs) of T-1 mapping and ADC were very good at <2.9%. Intra class correlations (ICCs) were high for cortex perfusion (0.801), cortex and medulla T-1 (0.848 and 0.997 using SE-EPI), and renal artery flow (0.844). In response to hypercapnia, a decrease in cortex T-2* was observed, whilst no significant effect of hyperoxia on T-2* was found. In CKD patients, renal artery and vein blood flow, and renal perfusion was lower than for healthy participants. Renal cortex and medulla T-1 was significantly higher in CKD patients compared to healthy participants, with corticomedullary T-1 differentiation reduced in CKD patients compared to healthy participants. No significant difference was found in renal T-2*.
Conclusions: Multiparametric MRI is a powerful technique for the assessment of changes in structure, hemodynamics, and oxygenation in a single scan session. This protocol provides the potential to assess the pathophysiological mechanisms in various etiologies of renal disease, and to assess the efficacy of drug treatments.

• 出版日期2017-9-14