Change of External Urethral Sphincter Function in Prostatic Patients

External urethral function was urodynamically examined in 13 patients with benign prostatic hypertrophy (BPH) associated with chronic urinary retention and in 5 volunteers. Prevoiding drop in external urethral sphincter pressure was noted in all the volunteers, whereas it was not found in 6 of the 13 cases of BPH. Bladder neck opening pressure was higher in these 6 cases (p