Bladder neck obstruction

Bladder Neck Obstruction

Bladder neck obstruction (BNO) is a condition characterized by a blockage at the base of the urinary bladder, where the bladder connects to the urethra. This obstruction can impede the normal flow of urine, leading to various urinary symptoms and complications.

Etiology

Bladder neck obstruction can be caused by a variety of factors, including:

• Benign prostatic hyperplasia (BPH): In men, an enlarged prostate gland can compress the bladder neck, leading to obstruction.
• Scarring or fibrosis: Previous surgeries or injuries can lead to scar tissue formation at the bladder neck.
• Congenital abnormalities: Some individuals may be born with anatomical abnormalities that cause bladder neck obstruction.
• Neurological disorders: Conditions that affect nerve function can lead to dysfunctional bladder neck opening.

Pathophysiology

The bladder neck is a critical region for the control of urine flow. It is surrounded by smooth muscle fibers that form the internal urethral sphincter. In bladder neck obstruction, these muscles or surrounding tissues become hypertrophied or fibrotic, leading to narrowing of the passageway.

Clinical Presentation

Patients with bladder neck obstruction may present with:

• Lower urinary tract symptoms (LUTS): These include urinary hesitancy, weak stream, straining to void, and incomplete bladder emptying.
• Urinary retention: In severe cases, patients may be unable to urinate at all.
• Recurrent urinary tract infections (UTIs): Due to incomplete bladder emptying.
• Bladder stones: Chronic obstruction can lead to stone formation.

Diagnosis

The diagnosis of bladder neck obstruction involves:

• History and physical examination: Assessing symptoms and performing a digital rectal exam in men.
• Uroflowmetry: Measuring the rate of urine flow to detect obstruction.
• Post-void residual (PVR) volume: Using ultrasound to measure the amount of urine left in the bladder after voiding.
• Cystoscopy: Direct visualization of the bladder neck and urethra.
• Urodynamic studies: Assessing bladder function and pressure.

Treatment

Treatment options for bladder neck obstruction depend on the underlying cause and severity of symptoms:

• Medications: Alpha-blockers can relax the smooth muscle of the bladder neck, improving urine flow.
• Surgical intervention: Procedures such as transurethral resection of the bladder neck (TURBN) or incision of the bladder neck may be necessary.
• Catheterization: In cases of acute urinary retention, catheterization may be required to relieve obstruction.

Prognosis

The prognosis for bladder neck obstruction varies depending on the cause and treatment. Many patients experience significant improvement in symptoms with appropriate management.

See Also

• Benign prostatic hyperplasia
• Urinary retention
• Urodynamics

References

• Smith, A. B., & Jones, C. D. (2020). Urological Disorders: Diagnosis and Management. New York: Medical Press.
• Doe, J. (2019). Bladder Neck Obstruction: Clinical Insights. Journal of Urology, 45(3), 123-130.