Ureterovaginal fistula should best be treated by-

In case of ureteric transection ,paial or complete,a pyelography fails to show pa or whole of the ureter on the transected site and there may be pooling of dye in the peritoneal cavity. The immediate treatment is percutaneous nephrostomy and retrograde dye injection under fluoroscopy to help identify the site of transection. In a case of complete transection urinary diversion by nephrostomy is advisable to tide over the crisis,followed later with repair surgery. In case the transection is recognised during the surgery ,the surgeon must undeake anastamosis at the site of injury or implant the cut end of the ureter into the bladder or perform a Boari flap operation of Ureteroneocystostomy. SHAW&;S TEXTBOOK OF GYNAECOLOGY,Pg no:187,15th edition