TRANSRECTAL SONOGRAPHIC INVESTIGATION OF URETHRAL AND PARAURETHRAL STRUCTURES IN WOMEN WITH STRESS URINARY-INCONTINENCE

Transrectal sonography of the urethra was used in 14 asymptomatic volu nteers, 37 women with frequency-urgency syndrome, 42 patients with mil d stress urinary incontinence, and 18 with severe stress urinary incon tinence. Transverse scanning over the midurethra was performed and cro ss-sectional images of the urethral and paraurethral structures were c ompared among the four with P < 0.05 being considered statistically si gnificant. The total cross-sectional area of the midurethra was signif icantly smaller in patients with stress urinary incontinence than in t hose without this disorder (86.7 +/- 29.9 versus 104 +/- 35.6 mm(2), P = 0.005); this difference resulted from a significantly smaller perip heral striated muscle component in patients with stress urinary incont inence (42.8 +/- 20.7 versus 58.3 +/- 27.3 mm(2), P = 0.001). The thic kness of the urethropelvic ligaments was significantly thinner in pati ents with stress urinary incontinence than in those without (5.9 +/- 1 .7 versus 8.9 +/- 2.1 mm, P < 0.001). The distribution of the peripher al striated muscle around the urethra was variable: complete surroundi ng the urethra was noted in 35.7% of the control women and in 48.6% of frequency-urgency patients, but only in 16.7% of patients with mild s tress urinary incontinence and 5.3% of patients with severe disease. B ladder neck incompetence was seen in 42 patients with stress urinary i ncontinence but in none of the control women. The length of the pubour ethral ligaments was similar in the four groups. Our finding showed th at stress urinary patients had a smaller striated muscle component in the midurethra and thinner urethropelvic ligaments. These defects in t he continence mechanisms might have great implications in the pathophy siology of stress urinary incontinence. Transrectal sonography of the urethra is a valuable investigative tool in assessing urethral and par aurethral conditions in patients with stress urinary incontinence befo re deciding treatment modality.