Laparoscopic Midsagittal Hemicystectomy and Replacement of Bladder Wall with Small Intestinal Submucosa and Reimplantation of Ureter into Graft

Abstract

Background and Purpose:

A variety of biodegradable organic materials have been used for bladder wall replacement. In some instances, partial replacement has been done using laparoscopic reconstructive techniques. However, to date, this activity has been limited to small patches. Herein, we present the initial experience with laparoscopic sagittal hemicystectomy and the use of laparoscopic reconstructive techniques to replace half of the bladder with small-intestinal submucosa (SIS) and to reimplant the ureter into SIS.

Materials and Methods:

Six female minipigs (20–25 kg) underwent transperitoneal laparoscopic sagittal hemicystectomy; the excised bladder wall was replaced with a 5 × 15-cm patch of SIS (Cook Biotechnology, Spencer, IN). The ipsilateral ureter was reimplanted through a small incision in the graft and secured with two sutures. Cystoscopy and cystometrograms were performed under general anesthesia preoperatively and at 6 and 12 weeks postoperatively. Tissues were harvested at 12 weeks.

Results:

The procedure was successful in six animals (left three, right three). During cystoscopy at 12 weeks, the area of the graft was not distinguishable from normal mucosa. Cystometrograms revealed maintenance of volume and compliance, with volumes of 338, 343, and 369 mL and intravesical leak-point pressures of 37, 59, and 39 cm H₂0 at 0, 6, and 12 weeks, respectively. Antegrade ureterograms demonstrated extrinsic obstruction, minimal (two), moderate (three), or complete (one), at the ureterovesical junction. The kidney associated with the completely obstructed ureter was grossly hydronephrotic at sacrifice. Histologically, patchy epithelialization of the graft with a mixture of squamoid and mature transitional-cell epithelium was found.

Conclusions:

Laparoscopic hemicystectomy with replacement of the bladder wall and implantation of the ureter into the SIS graft is a feasible procedure. Clinical application awaits improvements in the method of ureteral reimplantation and longer follow-up to assess for ingrowth of muscle and nerve fibers.