Magnetic resonance angiography in potential live renal donors: a joint radiological and surgical evaluation

To assess the impact of a joint surgical and radiological audit on the accuracy of contrast-enhanced magnetic resonance angiography (MRA) reports in the evaluation of potential renal donors.

We analysed the records of live renal donors who underwent gadolinium-enhanced MRA as part of the pre-operative evaluation to assess renal vasculature between August 1999 and July 2002 when feedback from surgical findings to radiology had been available. In cases of discrepancy between MRA reports and surgical findings, studies were retrieved from the magnetic resonance imaging (MRI) workstation and subjected to detailed joint clinical and radiological review. Scan quality was assessed and sources of discrepancy were identified.

There were 45 donors, 23 men and 22 women with a mean age of 41 years. Reported MRA findings were fully confirmed at surgery in 38 of 45 cases. These images were not analysed further. In seven donors the findings at surgery were discrepant with the radiological reports: there were four cases of "missed" early branches and three cases of "missed" accessory arteries. In the first year of the audit there were four discrepant cases out of 18 (22%), all of which were radiological reporting errors. The number of discrepant cases in the second year was two out of 19 cases (11%). Neither of these was a radiological reporting error. There was one "missed" early renal artery branch in the third year of audit, which was identified on MRA review.

The study highlights the importance of detecting and clearly reporting not only accessory renal arteries, but also early renal arterial branches in the pre-operative evaluation of renal donors. The accuracy of pre-operative MRA in potential renal donors is high, but radiological reporting of MRA examinations is improved through careful clinical feedback, audit and interdisciplinary co-operation.