Minimally Invasive Endourological Techniques may Provide a Novel Method for Relieving Urinary Obstruction due to Ureterosciatic Herniation.

Ureterosciatic herniation, the protrusion of the hernia sac through the sciatic foramen, is an extremely rare cause of ureteral obstruction. We describe a case revealed by severe left back pain in a 72-year-old female. She was referred to our hospital for urological assessment of left hydronephrosis observed by ultrasonography. Intravenous ureterography (IVU) showed findings compatible with a left sciatic ureter, a dilated ureter with a fixed kinking, which is known as the 'curlicue' sign. We decided to attempt recovery of the herniated ureter using a retrograde approach. Ureteral stent placement was performed to decompress the dilated upper urinary tract. The ureterosciatic hernia was relieved with the passage of a flexible guide wire and a double-pigtail stent. Three months after ureteral stenting, she refused continuing to have an indwelling stent and the stent was removed. Thereafter, IVU revealed recurrent ureterosciatic hernia; however, there was no hydroureter or hydronephrosis. The patient is currently being under observation for 6 years after stenting and continues to be without hydronephrosis or symptoms. Placement of an internal stent possibly provides the rigidity to the ureter, thereby reducing the hernia and urinary obstruction. In the previous reports, most symptomatic patients have been treated surgically, with conservative therapy reserved for asymptomatic patients. For the patient who is elderly or a poor surgical candidate, retrograde stenting may provide safe reduction and efficacious treatment. This endourological approach provides a minimally invasive means for the management of urinary obstruction caused by ureterosciatic herniation.