Prospective Comparison of 3-Dimensional Volume Rendered Computerized Tomography and Conventional Renal Arteriography for Surgical Planning in Patients Undergoing Laparoscopic Donor Nephrectomy

Abstract

We prospectively assessed the accuracy of 3-dimensional (3-D) volume rendered computerized tomography (CT) and conventional renal arteriography to visualize renovascular anatomy in patients undergoing laparoscopic donor nephrectomy. A total of 60 consecutive patients undergoing laparoscopic donor nephrectomy (left side in 46 and right side in 14) prospectively underwent 3-D CT and renal angiography. A short videotape of 3-D CT was prepared using volume rendering software that demonstrated the anatomical location, number, anomalies and spatial interrelationships of the renal arteries and veins. These 3-D videotapes and arteriogram findings were directly correlated with intraoperative surgical findings at laparoscopy and during ex vivo bench preparation of the harvested kidney. The perceived intraoperative value of 3D-CT to delineate renovascular anatomical detail was scored subjectively by the laparoscopic surgeon for each case on a 10-point scale of 0—completely inaccurate to 10—completely accurate. There were no complications related to the 3-D CT protocol and volume rendering was successful in all patients. Three-D CT accurately identified the number of renal arteries in 59 patients (98%). In 1 patient with 3 renal arteries 3-D CT and arteriogram each identified only 2. In the 46 patients undergoing left donor nephrectomy 3-D CT accurately identified the number of veins and venous anomalies in 45 (98%), including 2 with a circumaortic left renal vein. Another case of circumaortic vein was misdiagnosed as 2 renal veins. On the right side in 14 patients 3-D CT accurately identified the renal veins in 13 (94%) and missed 1 vein in a patient with 2 renal veins. Angiography correctly identified the number of renal veins in only 52 cases (87%). Furthermore, it misdiagnosed all 3 cases of circumaortic left renal vein. The laparoscopic surgeon believed that 3-D CT accurately identified the location and anatomical interrelationship of the renal vessels with precision. Mean subjective score ± SEM was 8.5 ± 1 for the arterial system, 8.6 ± 1.1 for the venous system and 9.2 ± 0.5 for any vascular anomalies. Three-D CT accurately identifies renal vascular anatomy in a manner that may facilitate renal hilar dissection during laparoscopic donor nephrectomy, especially during the initial surgeon experience. This imaging modality integrates essential information from angiography, venography and excretory urography into a single study, and it can obviate the need for more invasive vascular imaging in most cases.