A MODIFIED EXTRAVESICAL URETERAL REIMPLANTATION TECHNIQUE USING AN "INVERTED-Y" DETRUSOR DISSECTION

Background: Extravesical ureteral reimplantation has classically been performed with a detrusor dissection involving full mobilization of the ureterovesical junction (UVJ) until the ureter is attached only by the bladder mucosa. The UVJ is then advanced distally, and a distal ureteral anchoring stitch is used to prevent prolapse of the ureter out of the detrusor tunnel. As an alternative simplified approach, detrusor dissection can be performed in the shape of an inverted-Y, mobilizing only the proximal and lateral aspects of the UVJ, leaving the distal trigonal and detrusor attachments intact. The UVJ remains at the original position in this technique, anchored in place by its natural distal attachments, obviating the need for a distal anchoring stitch. It was the objective of this project to assess the merits and outcome of the "inverted-Y" detrusor dissection. Methods: From July 1997 to April 1999, 18 unilateral and 16 bilateral extravesical ureteral reimplantations (50 ureters) were performed using the inverted-Y detrusor dissection, employing either a laparoscopic approach or an open incision. All patients were monitored prospectively. Voiding efficiency was assessed by uroflowmetry and ultrasound post-void residual volume measurements at 2 days, 2 weeks and 2 months post-operatively. Upper tract imaging and voiding cystourethrogram were obtained 2 months post-operatively, and renal ultrasound was performed at 1 year. Results: Satisfactory kink-free extravesical ureteral reimplantations were achieved in all 50 ureters using the inverted-Y detrusor dissection. All ureters remained well anchored in their natural positions using this technique, without requiring a distal ureteral anchoring stitch. The inverted-Y detrusor dissection was technically simple to perform, and was less time consuming. Follow-up to date demonstrates no post-operative ureteral obstruction (100% patency), and persistent reflux was seen in only one ureter (98% reflux resolution). Urethral catheters were successfully removed 1 or 2 days post-operatively with no urinary retention noted. Voiding efficiency using the inverted-Y technique compares favorably to reported series, where a 4 to 21% rate of post-operative urinary retention has been reported in extravesical bilateral ureteral reimplantations (p=0.036). Conclusions: The inverted-Y detrusor dissection maintained a high rate of successful outcome (100% patency, 98% reflux resolution), comparable to the traditional techniques. The