Miniature Intravesical Urethral Lengthening Procedure for Treatment of Pediatric Neurogenic Urinary Incontinence

Purpose: Resistance to flow in a fluid conduit is proportional to tube length divided by the radius to the fourth power (Poiseuille's law). We report the results of a miniature intravesical urethral lengthening procedure where outlet resistance is increased by minimizing the diameter of the intravesical urethral tube. Materials and Methods: Nine pediatric patients with preoperative intractable incontinence underwent the miniature intravesical urethral lengthening procedure along with continent catheterizable stoma (9 patients) and bladder augmentation (8). The intravesical portion of the urethral lengthening was 3 cm (traditionally 6 cm), and the urethra was tubularized around an 8Fr feeding tube (traditionally a 16Fr catheter). After the tubularized caudal portion was tunneled under the trigone the cephalad part of the urethra was placed as an onlay to the posterior bladder wall without ureteral reimplantation. Results: At a mean followup of 31 months (range 10 to 47) 8 patients reported dry intervals of 3 hours or more, with minor leak per urethra only if they were overdue on the catheterization schedule. Mean postoperative abdominal leak point pressure was 71 cm H₂O (range 28 to 116). Upper tracts were well preserved in all patients. One patient required bladder neck closure for intractable incontinence. Conclusions: The miniature intravesical urethral lengthening procedure requires minimal bladder tissue and is easy to perform. It appears to be an effective alternative in bladder neck reconstructive techniques, avoiding the need for ureteral reimplantation due to its small size, while functioning as a pop-off valve when the bladder is overly full. This procedure should be avoided in patients who lack a trigonal bar.