The left renal entrapment syndrome: diagnosis and treatment.

A retrospective analysis was performed to review 20 patients with left renal vein (LRV) entrapment syndrome. All cases were diagnosed based on ultrasonography, magnetic resonance angiography, and renal venography. Technical success was achieved in all patients. Transposition of superior mesenteric artery was performed in three cases, transposition of LRV in two, and stent implantation in the LRV in 15. Stent migration occurred in one case, and stent reimplantation was performed. One case suffered from hematoma after transposition of the superior mesenteric artery, and reoperation was performed. Follow-up was made from 6 months to 6 years after the operation. Abnormalities were not found in the urine test of 18 patients and their symptoms disappeared. Two cases still had microscopic hematuria after exercise. All surgical operations are effective for nutcracker syndrome except excessive invasiveness. Stent may be one of the mainstream therapies because of its minimal invasiveness.