Experimental data on the application of a stoma prosthesis in cutaneous ureterostomy.

The main problem with urinary diversion via cutaneous ureterostomy is stomal stenosis. Results with experimental and clinical implants of carbon polymer stoma prostheses (max. clinical observation period: 31 months) for vesicostomies have encouraged us to find out whether implants of this material would be suitable for cutaneous ureterostomies as well. The first step was dilation of the ureters in 16 mongrel dogs, 4 mini pigs and 4 sheep. This was done by knotting a thread over a splint which had been introduced into the ureter. After 7 days the ureter was ligated prevesically and a carbon polymer stoma was implanted into the ureter. 37 of the 48 stoma implants were well tolerated and provided water tight urinary drainage; slight encrustation occurred, but, radiologically, a smooth flow of contrast medium was seen. Ten of these 37 cases had transient urinary leakage. Eleven of the 48 stoma implants were unsuccessful because of insufficient healing, urinary extravasation, parastomal inflammation or severe encrustations. The results of these experiments on animals would seem to justify initial clinical use. It is conceiveable that this way stomal stenosis of the cutaneous ureterostomy can be avoided.

Biocarbon urinary conduit: laboratory experience and clinical applications.

A new urinary conduit utilizing pure vitreous carbon has been used successfully in dogs. Pure carbon appears to be inert with respect to urine and urothelium. Lack of urinary salt encrustation on the exposed surface provides a well-functioning urinary conduit for vesical drainage. Twenty-one vesicostomies were performed in dogs. Careful follow-up and histologic studies of removed specimens were done to establish the biocompatibility of pure carbon. All vesicostomies functioned well. A description of the device, protocol, and results of laboratory experimentation are outlined. The surgical procedure is explained in detail. Results encourage the clinical trial of these devices in humans. Indications include patients with neurogenic vesicla dysfunction and those with total urinary incontinence, both of which require permanent indwelling catheters.