Upsizing of the artificial urinary sphincter cuff to facilitate spontaneous voiding

Following placement of an artificial urinary sphincter (AUS) in the male child, functional and mechanical alterations can ensue, resulting in an inability to void spontaneously. One possible mechanical etiology in the patient entering puberty is prostatic growth within the fixed mechanical confines of the AUS cuff, resulting in progressive bladder outlet obstruction. Unrecognized infravesical obstruction can, in turn, lead to upper urinary tract deterioration, sepsis, or renal failure. We evaluated the effect of somatic growth and maturation of the male urethra on voiding dynamics in boys with an AUS to specifically determine whether revision of the sphincter cuff (ie, upsizing) is beneficial in restoring the ability to void spontaneously.

A retrospective review of 124 children with an AUS was performed. Eleven boys were identified whose bladder neck cuffs were later upsized in an attempt to improve bladder emptying. All boys were prepubertal at the time of original cuff placement. The average interval between the initial operation and cuff upsizing was 5 years.

Following original sphincter placement, 8 patients emptied to completion spontaneously and 3 patients emptied by intermittent catheterization. All eight of the spontaneous voiders experienced progressive difficulty emptying after they entered puberty and ultimately had to rely on clean intermittent catheterization to empty completely. Follow-up subsequent to cuff exchange averaged more than 5 years (range 1 to 10 years). Despite an average increase of 10 mm in cuff size, all patients continued to depend on intermittent catheterization to empty completely.

Upsizing the bladder cuff in the maturing male who experiences difficulty with bladder emptying does not restore the ability to void spontaneously.