Anomalies of the external urethral meatus in girls with non-neurogenic bladder sphincter dysfunction

To investigate in a prospective study the clinical and urodynamic characteristics associated with the correlation previously reported between non-neuropathic bladder sphincter dysfunction and minimal meatal deformities in girls.

From January 1995 to June 1996 all girls referred for urodynamics to investigate non-neuropathic bladder sphincter dysfunction were examined for meatal anomalies. Two types of meatal anomalies were recognized, i.e. hypospadias, in which the urethral meatus is displaced dorsally and meatal web or covered hypospadias, in which there is a mucosal web on the dorsal side of the urethral meatus that deflects the urinary stream anteriorly. The girls presenting with minimal meatal deformities were compared with those presenting a normal meatal configuration for their history and video-urodynamic features.

During the study, 288 girls were referred for video-urodynamics; 88 presented with meatal anomalies (24 hypospadias and 64 covered hypospadias) and comprised the study group; all other girls were considered as the control group. Incontinence during the day was more frequent in the study group (56%) than in the control group (34%) (P=0.003). Nocturnal enuresis was more frequent in the control group (87%) than in the study group (68%, P=0.006). Urge was more frequent in the study group (80%) than in the control group (65%, P=0.02), as was anterior deflection of the urinary stream (voiding over the toilet rim), in 48% and 4.5%, respectively (P<0.001). On video-urodynamics, dysfunctional voiding (detrusor sphincter dyscoordination during voiding) was more frequent in the study group (59%) than in the control group (38%, P=0.009), and vaginal voiding was more frequent in the study group (40%) than in the control group (11.5%, P<0.001).

Girls presenting with meatal anomalies have more severe dysfunction, as estimated by urodynamics. Although the natural history of these anomalies and the incidence in the normal population is not known, it is thought that there is an aetiological correlation between the functional voiding disorders and the meatal anomaly. Surgical treatment to correct the anomalies is proposed.