THE EFFECT OF POSTERIOR WALL SUPPORT DEFECTS ON URODYNAMIC INDEXES INSTRESS URINARY-INCONTINENCE

Objective: To determine if posterior vaginal wall defects affect urody namic indices and mask stress urinary incontinence. Methods: Ninety wo men with grade 0, 1, 2, or 3 posterior wall defects were evaluated pro spectively by complete urodynamics to assess their urinary complaints. None had severe anterior or apical support defects. Urethral pressure profilometry and cough stress test were performed with the posterior wall in the unretracted position and then with the posterior wall retr acted using a split speculum. Analysis of covariance was used to compa re adjusted mean differences in maximum urethral closure pressure, fun ctional urethral length, and units of leakage volume during the cough stress test in the unretracted and retracted positions among the poste rior wall grade groups. Results: In women with grade 3 posterior wall defects, there were significant changes from the unretracted to the re tracted position in maximum urethral closure pressure of -7.0 cm H2O, (99% confidence interval [CI] -12.4, -1.6), functional urethral length of -0.3 cm (99% CI -0.5, -0.1), and leak volume units of +0.7 (99% CI 0.4, 1.0) during the cough stress test. There were four women with gr ade 3 posterior wall defects who demonstrated potential stress inconti nence when their posterior wall was retracted. Conclusion: A grade 3 p osterior wall defect may artificially raise maximum urethral closure p ressure, increase functional urethral length, and mask urinary stress incontinence during a cough stress test. Women with grade 3 posterior wall defects should be tested with the posterior wall retracted during urodynamic evaluation. (C) 1998 by The American College of Obstetrici ans and Gynecologists.