Subtrigonal phenol injections in the treatment of idiopathic detrusor instability in the female--a long-term urodynamic follow-up.

A total of 36 subtrigonal phenol injections were performed on 29 patients with detrusor instability. Long-term follow-up (mean 13.7 months) showed a subjective response rate of only 14%, and objectively there was no significant change in any urodynamic parameter in the group as a whole. There was, however, a significant improvement in cystometric capacity and volume at first contraction, in those under 55 years of age. One patient developed a vesicovaginal fistula following repeat injections. This suggests that subtrigonal phenol injections have little place in the treatment of detrusor instability, especially in the over 55s, and repeat injections should be abandoned because of the risk of major complications.