The incidence of detrusor instability before and after colposuspension: a study using conventional and ambulatory urodynamic monitoring

Objective To determine the incidence of detrusor instability (DI) detected by conventional and ambulatory bladder pressure monitoring, any link betwee n urodynamic findings before and after colposuspension, and between patient s' symptoms and the urodynamic findings. Patients and methods Sixty-five patients, scheduled to undergo colposuspens ion on the basis of pure genuine stress incontinence on conventional cystom etrography (CMG), also underwent ambulatory monitoring (AM) before surgery. All were requested to return 3 months afterward for repeat CMG and AM in r andom order. In all, 56 patients completed all assessments before and after surgery. In addition to the urodynamic assessment, the patients' symptoms before and after surgery were compared using a detailed questionnaire. Results On AM before surgery, half the patients showed some DI; afterward, the incidence on AM was 70% and on CMG was 27%. However, on AM, 25% of pati ents who had DI before surgery showed no evidence of it afterward. Of the 1 9 women who complained of urgency preoperatively, 16 showed DI on preoperat ive AM. However, of the 37 women denying urgency preoperatively, 12 (32%) a lso showed evidence of DI on preoperative AM. Conclusions There is a significant incidence of DI detected by CMG after co lposuspension in patients who are stable before surgery. The incidence of D I on AM was significantly higher than on CMG both before and after surgery. However, the preoperative urodynamic finding of increased DI on AM does no t exclusively predict its presence postoperatively on AM or CMG. In additio n, a patient history of urgency does not correlate well with the urodynamic findings before or after surgery. Therefore, from this study it appears th at the postoperative symptomatic or urodynamic state cannot be predicted re liably from those before surgery.