CT findings after left renal vein division during abdominal aortic surgery

The rationale behind left renal vein division (LRVD) is the assumption that adequate collateral draining channels will develop.

To describe computed tomography (CT) findings after LRVD during aortic surgery.

Among 61 consecutive patients who underwent LRVD during aneurysm repair or revascularization for aortic occlusive disease between January 2003 and December 2017, 51 patients (40 men, mean age 71.4 ± 8.4 years) were enrolled. Contrast-enhanced CT images were analyzed to evaluate collateral drainage, patency, left renal vein diameter, and left renal parenchymal thickness. A total of 115 radiologic reports were reviewed to check whether these findings were accurately mentioned.

The median time period of the first postoperative follow-up CT was 36 days (range 7-1351 days). The gonadal vein (n = 47) was the most common collateral draining channel, followed by the retroperitoneal veins (n = 42) and adrenal vein (n = 33). Thrombosis occurred in five patients between postoperative days 7 and 17 in the remnant renal vein (n = 3), remnant renal vein plus gonadal and adrenal veins (n = 1), and gonadal vein (n = 1). There was a significant decrease in renal vein diameter (-0.48 ± 2.12 mm, P = 0.006). There was no significant difference in parenchymal thickness (-0.25 ± 1.27 mm, P = 0.193). Neither LRVD nor any associated findings were correctly stated on radiologic reports.

Postoperative contrast-enhanced CT can delineate collateral draining channels and complications following LRVD. However, these findings tend to be either missed or misinterpreted.