Comparison of gadodiamide-enhanced MR angiography to intraarterial digital subtraction angiography for evaluation of renal artery stenosis: Results of a phase III multicenter trial

Purpose: To evaluate the efficacy and safety of 0.1 mmol/kg gadodiamide administration for contrast-enhanced magnetic resonance angiography (MRA) in detecting hemodynamically relevant renal artery stenosis (RAS) when compared with intraarterial digital subtraction angiography (IA-DSA) as the gold standard. Materials and Methods: In a multicenter, controlled study, 395 patients with suspected or known RAS were included. Three independent readers evaluated the MRA images. Two readers evaluated the IA-DSA images and subsequently achieved consensus. The sensitivities and specificities of gadodiamide-enhanced MRA were analyzed at the per-patient and per-vessel levels (exact 1-sided binomial test at a α 0.025 with 95% confidence interval). Results: A total of 335 patients who had available standard of truth and MRA tests were included in the all-subjects efficacy population: 55.5% (186/335) men and 44.5% women with a mean age of 63 ± 13 years (range 17-85 years). The sensitivities and specificities ranged from 81% to 86% for all independent readers at the per-patient analysis based on subjects with the diagnostic images. Similar results were achieved with per-vessel level analysis. Fewer than 1% of patients had adverse event associated with gadodiamide administration. There were no cases of nephrogenic systemic fibrosis (NSF) reported. Conclusion: Gadodiamide administration at the labeled dose of 0.1 mmol/kg for contrast-enhanced MRA achieved equivalent results compared to IA-DSA in evaluation of RAS and was well tolerated.