Utility of 16-multidetector CT angiography in the preoperative evaluation of vascular and ureteral anatomy of donor nephrectomy

Abstract

Objective: To evaluate the accuracy of 16-section multi-detector row computed tomography (MDCT) angiography in the preoperative evaluation of renal transplant donors in comparison with intra-operative findings. Patients and methods: In this prospective study 89 consecutive renal donors (69 men and 20 women) underwent 16-MDCT angiography followed by open surgical donor nephrectomy from January 2008 to March 2010. We reported the number and origin of renal arteries and the presence of early branching arteries. Renal venous anatomy was evaluated for the presence of major and minor venous anomalies. The renal calyces and ureters were assessed with delayed excretory phase images. On a 3D workstation, images were evaluated by the radiologist and the urologist. These CT angiography results were compared with surgical findings. Results: The mean age of the donors was 31 years. Open donor nephrectomy was performed on the left in 52 and on the right in 37 subjects. At surgery, accessory renal arteries were found in 14 kidneys (double arteries to 13 kidneys and triple arteries to one kidney). CT and surgical findings agreed in 92% of subjects. Seven small accessory renal arteries in seven donors were missed by radiology reviewers. Early branching of the renal arteries was shown in 5 arteries, and CT matched surgical findings in 88 cases (99%). Renal vein anomalies were present in six subjects, three of them were missed with the preoperative CT. The major shortcoming of MDCT angiography was noted in identifying minor venous anatomy. The presence of discrepancies between pre-operative MDCT and the findings at surgery did not affect the clinical outcome of transplantation, except in one case where intra-operative surgical distress was noted due to failure in identifying multiple major renal veins. Conclusions: 16-MDCT angiography is a good modality in the pre-operative evaluation of live renal donors. However, it provides suboptimal information on renal vascular anatomy, particularly complex venous patterns. Surgeons should not rely fully on pre-operative CT angiography while performing donor nephrectomy.

Keywords: Transplantation; Kidney; Evaluation; Donor

African Journal of Urology (2013) 19, 7–12