Does bladder wall thickness decrease when obstruction is resolved?

The aim of the current study was to determine if sonographic bladder wall thickness diminishes after symptomatic obstruction is resolved in female patients after stress incontinence surgery.

Between December 2008 and December 2010, 62 female patients with symptomatic bladder outlet obstruction, as defined by Blaivas, who had undergone prior surgery for urinary stress incontinence were included in the study. The patients' history was taken and symptoms were noted. Patients underwent gynaecological examination, and multichannel urodynamic assessment was performed. Vaginal sonographic assessment of the bladder wall thickness (BWT) was performed before and after urethrolysis.

62 patients were included in this study, 55 of whom had undergone suburethral sling insertion and seven had Burch colposuspension. Postoperatively, BWT decreased significantly from 9.1 mm  ±  2.1 to 7.6 mm  ±  2.2 (p < 0.0001). In seven patients, obstruction was still unresolved postoperatively; of these, two had undergone a retropubic sling insertion and two had a Burch colposuspension. An ROC curve analysis showed a significant positive association between residual urine and persistent obstruction before surgery (AUC 0.76, 95%CI 0.58-0.94; p < 0.05).

If obstruction is resolved, bladder wall thickness decreases. Preoperatively elevated residual urine may increase the risk of persistent obstruction after urethrolysis.