Urethral Diaphragm / Web
The urethral diaphragm, sometimes termed the urethral web or membrane,
is a form fruste of posterior urethral valves or congenital
obstructing urethral membrane. It represents an unusual persistence
of bands of tissue arising from the fins of the urethral ridge.
These may join anteriorly to form a "bicuspid valve" rather than
complete membrane. When the membrane is complete or nearly so,
obstruction may occur and the condition of posterior urethral valves
and its obstructive uropathy follows. Patients with a urethral
membrane may be completely asymptomatic and most cases are found
incidentally during the work-up a urinary tract infection or
hematuria. It is possible that a subclinical obstruction may put the
patient at risk for infection, but there is no significant increased
incidence of vesico-ureteric reflux. If symptoms are persistent, fulgaration can be used to treat the valves.
Krishnan A, De Souza A, Konijeti R, Baskin L, The Anatomy and
Embryology of Posterior Urethral Valves. J Urol. 2006 Apr 175,
12214-1220
Imaji R, Moon DA, Dewan PA Congenital posterior urethral membrane:
variable morphological expression J Urol. 2001 Apr; 165(4):1240-2
A. Urethral diaphragm
B. Prostatic urethra
C. Distal urethra
Posterior urethral valves
Cobb’s collar
Plicae colliculi
