[A urodynamic study of detrusor hyperreflexia in benign prostatic hypertrophy].

Urodynamic study was performed on 48 patients with benign prostatic hypertrophy. Twenty six of the patients had detrusor hyperreflexia. The mean age of the patients with detrusor hyperreflexia was higher, the mean value of urinary frequency was greater, the mean value of bladder capacity was smaller and the mean value of maximum voiding pressure was higher than those of patients without detrusor hyperreflexia. Small bladder capacity and high voiding pressure of patients with detrusor hyperreflexia were improved 3 months postoperatively. Eight of the 14 patients with detrusor hyperreflexia had normal bladder function, but detrusor hyperreflexia of the resting 6 patients was persisting. The mean value of posterior urethral length on the urethral pressure profile of patients with persisting detrusor hyperreflexia was shorter than that of patients with improved detrusor hyperreflexia. This suggested that the shorter length of posterior urethra may be a causative factor for persisting detrusor hyperreflexia.