The effects of overstretching on the structure and function of the bladder in relation to Helmstein's distension therapy.

Measurements of the maximum bladder distensibility, cystometrograms and histological studies of the bladder after Helmstein's distension therapy show intramural fibrosis and a reduction in bladder capacity. When this is made worse by post-radiation fibrosis it may give rise to such severe contraction that diversion may be needed. There is no evidence that distension, of the type used here, ever gives rise to "stretching" or "atony" of the bladder: and it is questionable whether distension of a lesser degree, such as may be found in acute urinary retention, ever does so either.