Comparison of Non-Contrast Magnetic Resonance Angiography Using Inflow Inversion Recovery (Inhance) Technique and Contrast-Enhanced Magnetic Resonance Angiography in the Assessment of Renal Arteries of Patients with Hypertension

Abstract

Background: Renal artery stenosis can cause renovascular hypertension manifesting clinically as high blood pressure. Objectives: In this study, we determined the efficiency of non-contrast magnetic resonance angiography (NC-MRA) using the inflow inversion recovery (inhance) method in the evaluation of renal arteries of hypertensive patients. Patients and Methods: Three-dimensional (3D) contrast-enhanced magnetic resonance angiography (CE-MRA) and NC-MRA were used to prospectively evaluate 66 patients diagnosed with hypertension. 3D CE-MRA and digital substractional angiography served as the gold standards. Image quality, number of main/accessory renal arteries, and main renal artery diameters were assessed. Statistical analyses were based on paired-t tests and intra-class correlation coefficients. Results: Of the 126 main renal and 12 accessory renal arteries reviewed in this study, NC-MRA overall image quality was good or excellent in more than 89.5%. An image quality of 94% was recorded for both left and right sides with CE-MRA. The differences between the 3D CE-MRA and NC-MRA readings for the renal artery ostium and proximal, medial, and distal segment diameters were not significant (P > 0.05). Inter-reader agreement regarding all segments was excellent. 3D CE-MRA was superior to NC-MRA in assessing accessory renal arteries (detection ratio using NC-MRA: 7/12, 58%). Conclusion: NC-MRA using the inhance method to image the anatomy of the renal artery provides an alternative to CE-MRA in patients with hypertension.