Unsuspected proximal urethral obstruction in young and middle-aged men.

Proximal urethral obstruction, a common cause of prostatism in young and middle-aged men, often is misdiagnosed as prostatitis, neurogenic bladder or a psychogenic voiding disorder. Simple urodynamic studies (uroflowmetry and cystometry) do not distinguish a poor flow owing to bladder neck obstruction from that caused by poor detrusor contractility in these patients. Only the simultaneous measurement of detrusor pressure and uroflowmetry can make this distinction. A total of 23 patients with unsuspected proximal urethral obstruction underwent synchronous video-pressure-flow electromyography studies, and were treated and followed for a minimum of 1 year. Treatment by transurethral prostatic resection or bladder neck incision almost always was curative but alpha-adrenoceptor blocking agents have not been effective. All patients who underwent transurethral prostatic resection or bladder neck incision at the 5 and 7 o'clock positions have had retrograde ejaculation but both patients who underwent unilateral bladder neck incision reported antegrade ejaculation.