Etiologic Classification of Female Urethral Syndrome by Urodynamic Study

Jin, Myeong Heon; Lee, Jeong Gu

Abstract

PURPOSE: The symptoms of female urethral syndrome (FUS) can originate from mechanical or functional obstructions of the bladder neck or urethra. From retrospective reviews of women referred for evaluation of lower urinary tract symptoms (LUTS), 2.7 to 23% had urodynamic evidence of a bladder outlet obstruction (BOO). However, few urodynamic studies (UDS) have been performed on the prevalence of BOO in FUS. This study was aimed at identifying the causative factors of FUS symptoms, including BOO, as evidenced by UDS.
MATERIALS AND METHODS
One hundred and sixteen women with FUS were enrolled in our UDS evaluations. An additional 247 patients, presenting for evaluation of stress urinary incontinence (SUI), served as controls. Comparisons of the maximum flow rate (Qmax), voided volume, post-void residual, detrusor pressure at maximum flow rate (PdetQmax), maximum detrusor pressure (Pdetmax) were made between the FUS and SUI cases. By definition, the FUS cases were divided into normal, BOO, detrusor under activity, detrusor instability and low compliance. These sub-groups were compared with controls in a similar way.
RESULTS
Women with FUS showed a lower Qmax (15.9 versus 23.8ml/sec, p<0.05), higher post-void residual (86 versus 22ml, p<0.05), PdetQmax (24.0 versus 18.0 cmH2O, p<0.05) and Pdetmax (33.3 versus 27.9cmH2O, p<0.05) compared to those with SUI. The incidence of BOO, detrusor under activity and detrusor instability were 31.9, 25 and 16%, respectively, in the FUS group. Only 22% of women with FUS showed normal UDS findings.
CONCLUSIONS
These results indicated the importance of UDS in identifying the causative factors of the symptoms of FUS. Treatment of a BOO will help provide new treatment modalities for FUS.