To understand meatal stenosis, we should first study a bit of the urinary system. More specifically, it is important to know about the urethra and its anatomy.
The male urethra extends from the bladder neck to the urethral opening in the penis. Its length always depends on the individual’s age and penis length. In most cases, it measures around 18 centimeters with a diameter of 9 millimeters during urination.
It can be divided into the posterior urethra and anterior urethra. The former goes from the bladder neck to the corpus spongiosum of the penis. The latter is larger and surrounded by the corpus spongiosum.
What is meatal stenosis?
Meatal stenosis is the narrowing of the meatus in the anterior urethra, right where it opens to the outside. Thus, the normal pass of urine gets blocked. Patients with this condition have an upward urinary stream and have difficulties in aiming.
In some cases, they also have pain symptoms and urinary urgency. They are usually treated with surgical procedures known as mentoplasty or meatotomy (1).
What causes meatal stenosis?
Most cases of urethral meatus stenosis are triggered after circumcision. The meatus of circumcised boys is sometimes exposed to mechanical trauma. A wet diaper and constant rubbing may result in dermatitis (inflammation) of the skin. This process triggers the growth of excess tissue that blocks the urethral opening.
However, meatal stenosis may also form in other scenarios (1,2):
- In patients with prolonged or continuous use of urinary catheters
- As a result of penile trauma
- As a complication of hypospadias repair
- In patients with balanitis xerotica obliterans (BXO), lichen sclerosis, and other inflammatory problems
According to some authors, this problem can be prevented with petroleum jelly applied directly to the glans after circumcision.
The most important signs and symptoms in meatal stenosis typically include (1,3):
- Changes in the urine stream: The patient has difficulty in aiming his urinary stream. There are misdirection and high velocity of the urine flow with an upward-deflected direction. In some cases, there’s also a slight lateral misdirection due to an additional penile torsion.
- Dysuria: It means painful urination or a burning sensation when urinating. Not all patients have this problem, though.
- Propensity to stand back or sit to urinate: Patients resort to this measure to control their urinary stream.
- Bloodstains: They are usually found in the underwear, especially when trauma and inflammation are still ongoing.
- Increased frequency and urgency: Some patients may also report increased urinary frequency or a longer time to empty their bladder. They sometimes report urinary urgency, too.
The diagnosis of meatal stenosis is usually made by evaluating the patient and his symptoms. They are usually patients who underwent circumcision and report the symptoms listed above. One of the most critical physical exam findings is a urethral stricture with an upward-deflected urinary stream.
Doctors can also use a calibration of the urethral meatus with a lubricated feeding tube. In 1-year-old children and younger infants, a 5-French feeding tube passes without problems. Older children aged 1-6 years accept an 8-French feeding tube in normal circumstances.
The diagnosis is often delayed because not all boys receive proper follow-up after neonatal circumcision. Additionally, the signs and symptoms are more apparent when boys have started their toilet training. It should be differentiated from urinary infections, a prevalent diagnostic mistake.
There’s no additional investigation required for meatal stenosis because it does increase the risk of urinary tract infections or cause obstructive hydronephrosis. In some cases, a uroflow with electromyography is needed. This test measures how urine is moving in the urethra.
Other tests include a bladder capacity exam compared to a postvoid residual volume (voiding cystourethrogram). In patients with signs and symptoms of infections, a urinalysis with culture is also ordered. However, all of these tests are not usually required (1).
The best treatment for meatal urethral stenosis is mentoplasty or meatotomy. This procedure takes away the stuck part of the meatus (meatotomy) or uses stitches to keep it open (mentoplasty).
They are both cost-effective, but the former is more common and has more clinical evidence. There’s a very low incidence of recurrence or bleeding and a high patient tolerance level in clinic meatotomy.
Meatotomy can be performed under local anesthesia or general anesthesia, and the results are not significantly different. It all depends on how cooperative the patient is. Mentoplasty requires general anesthesia or sedation (4).
The most common complication is bleeding, followed by infections and recurrence of the condition. However, they are all uncommon and respond well to treatment (5).
After surgery, it is essential to adhere to the post-operative care recommended by the pediatric urologist. They usually order an ointment that should be applied after separating the meatus edges. It is administered twice daily for 2 weeks or as recommended by your healthcare provider. What it does is preventing the edges from adhering.
It sometimes has antibiotics, steroids, or a combination of topical drugs. In some cases, post-operative care also requires dilation with a feeding tube.
The child should preferably wear loose underwear after the procedure and for 24 hours. Playground activities, bicycle rides, and other active sports should be restricted for 3 or 4 days.
The patient may experience mild pain when urinating up to 2 days after the procedure. In most cases, this pain is caused by urinary retention, and parents are recommended to stimulate micturition by placing their child in a tube with warm water (5).
Newborn circumcision is a common practice in some countries. However, circumcised males are at a higher risk of meatal stenosis. This is a urethral stricture disease characterized by a narrowing of the anterior urethra.
Patients with meatal stenosis usually have problems trying to control their urinary stream. They may also report a burning sensation or painful urination. The condition is caused by inflammation and micro-trauma after circumcision.
It is a condition usually attended by a pediatric urology specialist through a surgical procedure. Meatotomy is the most common. It involves taking out the obstruction and administering ointments to prevent complications.