Posterior urethral valves

Posterior urethral valves are an obstructive congenital defect of the male urethra.

Classification

Posterior urethral obstruction was first classified by Hugh Hampton Young, urology pioneer, in 1919. More recent evidence suggests that obstruction in the posterior urethra is a COPUM (Congenital Obstructive Posterior Urethral Membrane), while the fibrous obstructive anomalies in the more distal urethra are remnants of the urogenital membrane, also called Cobb's Collar. These are equivalent to Young's type III lesions, which are not in the posterior urethra.

Diagnosis

• Abdominal ultrasound is of some benefit, but not diagnostic. Features that suggest posterior urethral valves are:
• Bilateral hydronephrosis.
• Thickened bladder wall
• Bladder diverticula
• Voiding cystourethrogram (VCUG) - diagnostic

Complications

• Incontinence
• Urinary tract infection
• Renal failure
• Vesicoureteral reflux

Treatment

There are three treatments of the posterior urethral valves:

• Vesicostomy and then valve ablation - making a stoma (a hole) in the urinary bladder, also known as high diversion, followed by closure of the stoma and valve abalation.
• Pyelostomy and then valve ablation - making a stoma (a hole) in the pelvis of the kidney, also known as high diversion, followed by closure of the stoma and valve abalation.
• Primary (transurethral) Valve ablation - removal of the valves through urethra, without stoma.

The standard treatment is primary (transurethral) ablation of the valves. Urinary diversion is used in selected cases, and its benefit is disputed.

Female homolog

The female homolog to the male verumontanum from which the valves originate is the hymen.

References