Background: This study was designed to test the hypothesis that decreased periurethral vascularization and blood flow might lead to urinary incontinence. Three-dimensional color histogram may better quantify the vasculature than traditional two-dimensional Doppler ultrasound imaging.
Methods: Between June 2002 and July 2003, 57 patients were invited to undergo three-dimensional power color Doppler study of the periurethral vessels before surgery. In group 1, 29 women with stress urinary incontinence underwent tension-free vaginal tape procedures and in group 2, 28 continent women underwent other procedures for treatment of benign gynecologic disease and without urological problems. We used 3 indices of color histogram to quantify the vascularization and blood flow within a tissue block from the bladder neck to the urethral meatus and the periurethral area within 5 mm of the urothelium borders. The values of 3 indices of histogram, vascularization index, flow index and vascularization-flow index, were analyzed.
Results: Judging from the values of vascularization index, flow index and vascularization-flow index generated in our study, significantly decreased periurethral vasculature was found in women with stress urinary incontinence and women in the postmenopausal status as compared with women in the continent group and those in the premenopausal status, respectively (p<0.05).
Conclusions: Three-dimensional histogram measurement revealed less periurethral vessels and flow in women suffering from stress urinary incontinence, a finding that might play a role in the pathogenesis of stress urinary incontinence.