Meatal Stenosis

After circumcision, a child who is not toilet-trained persistently exposes the meatus to urine, and this exposure results in inflammation (ammoniac dermatitis) and mechanical trauma as the meatus rubs against a urine-soaked diaper. Replacement of the delicate epithelial lining of the distal urethra by scar tissue may then result in fusion of the epithelial lining in the ventral meatus, leaving a narrow orifice at the tip of the glans. Because meatal stenosis is more commonly seen after circumcision, circumcision has been believed to be an important causative factor[5] ; however, the condition can also be seen in uncircumcised boys.[4]  

Research into other possible causative factors has identified some association with hypersensitivity reactions (atopic dermatitis, allergies, etc).[6] Meatal stenosis can also occur after hypospadias repair in approximately 3-10% of patients, depending on the severity of the hypospadias,[7]  and may require additional surgical repair.

Balanitis xerotica obliterans (BXO; also referred to as lichen sclerosus) is a less common cause of meatal stenosis, but as many as 20% of boys undergoing circumcision for BXO may require subsequent operative treatment of meatal pathology.[8]

Another hypothetical cause is ischemia due to damage to the frenular artery during circumcision, resulting in poor blood supply to the meatus and subsequent stenosis. In a prospective study of circumcised boys, Van Howe found meatal stenosis in 24 of 239 (7.29%) children older than 3 years; meatal stenosis was the most common complication of circumcision.[1]

Morris et al performed a systematic review and meta-analysis that assessed diagnosis of meatal stenosis after circumcision and the potential association of meatal stenosis with circumcision.[4]  They found that the risk of meatal stenosis after circumcision was low overall but that there was weak evidence suggesting a nonsignificantly higher prevalence in circumcised patients.

In a child who is circumcised, persistent exposure of the meatus to urine and mechanical trauma from rubbing against a wet diaper results in ammoniac dermatitis, loss of meatal epithelium, and fusion of its ventral edges. This results in a pinpoint orifice at the tip of the glans.

Other causes of meatal stenosis include the following:

• Previous  hypospadias repair or congenital abnormality of the distal urethra associated with hypospadias
• Trauma
• Prolonged catheterization
• BXO, an unusual condition that causes a whitish discoloration and dry appearance of the glans ^[9]

A 10-year retrospective series of boys with BXO at Boston Children's Hospital included 41 patients with a median age of 10.6 years, of whom 85% were aged 8-13 years.[10] The disease process was found to involve the prepuce, the glans, and sometimes the urethra. The most common referral diagnoses included phimosis (52%), balanitis (13%), and buried penis (10%). In 46% of the patients, circumcision was curative; 27% (11 patients) had meatal involvement that was treated by meatotomy and meatoplasty, and 22% required extensive plastic procedures of the penis, including buccal mucosal grafts.

Meatal stenosis occurs in as many as 20% of pediatric patients with BXO. Although BXO is difficult to treat, meatotomy typically produces a durable treatment of the meatal stenosis. Topical steroids or tacrolimus may also be used.[11]

Meatal stenosis has been estimated to affect as many as 9-20% of males who are circumcised. Children who are not toilet-trained are more prone to develop meatal stenosis after circumcision because of exposure of the meatus to urine in diapers. Most children who are toilet-trained can verbalize their difficulties during micturition to their caregivers.

Given the wide variances in the reported rates of meatal stenosis, the precise effect race or ethnicity may play in the development of this condition is difficult to determine. However, when studies from different countries have been compared, no obvious racial predilection has been identified.[4]

Meatal stenosis carries no known risk of mortality. The prognosis is excellent after surgery: Meatotomy or meatoplasty is typically curative of the misdirection of the urinary stream. Morbidity is limited to the clinical symptoms and complications of surgical repair, including bleeding, infection, and recurrence. If there are also voiding symptoms (eg, pain with urination or hesitancy), these may be related to underlying voiding dysfunction, and surgical correction of meatal stenosis may not alleviate them.

By far the most common presenting symptom is misdirection of the urine stream, typically in an upward direction. This can make it more difficult for boys to aim the urine. For this reason, meatal stenosis is rarely dectected prior to toilet training. Rarely, severe cases may give rise to obstructive symptoms such as difficult or painful urination.

In cases of suspected meatal stenosis, the best evaluation is by a primary care or specialist provider who can observe the the patient urinating (eg, by observing voiding in clinic or reviewing a patient-provided video).

Once meatal stenosis is present, it is unlikely to resolve without intervention.

The patient history may include the following:

• Difficult-to-aim (upward-deflected), high-velocity (long-distance) stream of urine; the misdirection of the urine stream is the most important feature of the history, in that this is what is most likely related to meatal stenosis and is most reliably corrected by meatotomy or meatoplasty; this is the most common presentation
• Some families also note lateral misdirection of the stream, which may be due to rotational torsion of the penis or twisting of the penis by the child during urination
• Pain upon initiation of micturition
• Need to stand back from toilet or sit during urination
• Burning at meatus
• Blood spots in underwear
• Urgent, frequent, and prolonged emptying of the bladder

It is important to note that symptoms other than misdirection of the urinary stream (eg, pain, urinary hesitancy, and frequency) may be signs of underlying voiding dysfunction rather than results of meatal stenosis. Consequently, these symptoms may not improve after correction of the meatal stenosis.

Meatal stenosis can be suspected on the basis of the presence of a small meatus during examination, particularly if, with lateral traction, the ventral edges of the meatus appear fused. However, a small-appearing meatus may be asymptomatic.

Observing an upwardly deflected narrow stream during urination is the most definitive examination finding; this demonstrates the clinical sign most reliably corrected with surgery.

The physician may desire to calibrate the meatus. Litvak et al reported that the meatus in children younger than 1 year will accept a lubricated 5-French feeding tube; they also reported that in children aged 1-6 years, an 8-French feeding tube should pass without difficulty.[12]

In general, meatal stenosis does not cause urinary tract infections, hydronephrosis, or any form of obstruction of the lower urinary tract. For this reason, no further urologic investigation is typically warranted, particularly if the only complaint is misdirection of the urine stream.

If the diagnosis is in question, observing the child void, with particular attention to the force of the stream (increased), the caliber of the stream (decreased), and the duration of the voiding episode (usually prolonged), is helpful. If an elimination disorder is suspected, noninvasive urodynamic studies (eg, as uroflow with electromyography [pad electrodes]) and measurement of bladder capacity and postvoid residuals may be helpful for confirming the diagnosis. If associated infection is suspected, urinalysis should be obtained. If the urinalysis is positive, a urine culture should be obtained.

In most cases of meatal stenosis, no imaging studies are recommended. Assessment of postvoid residual volume may be considered if there is concern about incomplete bladder emptying.

No universal standard staging or grading system has been adopted. A 2020 paper by Mekayten et al attempted to establish a validated grading system with three grades of meatal stenosis, as follows[13] :

• Grade 0 - No meatal stenosis, meatus wide open with good visualization of mucosa
• Grade 1 - Narrowed meatus, some visualization of mucosa, visible scar across part of the meatus
• Grade 2 - Pinpoint meatus, no visualization of mucosa, meatus nearly covered with scar tissue

A standardized grading system may improve documentation and communication between healthcare providers and families. The actual effect on clinical outcomes, however, remains unclear.

Nonoperative treatment has not been shown to be effective for this condition.

Serial urethral dilatation results in small tears of the meatus, which are followed by secondary healing and possible persistance or recurrence of scar tissue. In the long term, this may create a tighter stricture at the tip of the penis; therefore, this procedure is not recommended and is discouraged.

Meatotomy or meatoplasty is the definitive treatment for meatal stenosis. Meatotomy is a simple procedure in which the ventrum (bottom aspect) of the meatus is first crushed (for hemostasis) for 60 seconds with a straight clamp (the authors have found the striations of a small nontoothed bowel clamp to be ideal for this application, whereas others have found needle holders to be effective and prefer this method), then divided with fine-tipped scissors.

Brown et al reported excellent results following 130 office meatotomies, with only two recurrences of meatal stenosis and one patient with bleeding requiring stitches.[14] They also cited the cost-effectiveness of this treatment and noted good patient tolerance when a caring approach is used to reassure the child before and during the procedure. In this series, parents were encouraged to remain with the children during the operation; their presence seemed to have a calming effect.

In a retrospective study of 55 boys who underwent clinic meatotomy (CM) under topical lidocaine and prilocaine (EMLA) anesthesia, Fronczak et al found that although their success rate was lower than that reported in earlier studies and the incidence of pain higher, it was nonetheless possible to complete all of the CMs, and more than 90% of patients experienced resolution or improvement of their symptoms.[15] The cost of CM was approximately one tenth that of meatotomy performed under general anesthesia, with no evidence of inferiority evident in the literature.

If the caregivers and the patient are cooperative, meatotomy can be performed in the office of the physician with a topical eutectic mixture of local anesthetics (EMLA cream) applied liberally over the entire glans and secured in place for at least 30 minutes with an occlusive dressing. After being in place for 30 minutes, the dressing is removed, and the penis is prepared and draped into a sterile field.

Throughout the procedure, it is important to reassure the child and tell him what is being done.

One blade of a straight clamp is introduced into the meatus, and the ventrum of the meatus is crushed (~3 mm) by closing the clamp. This provides adequate hemostasis in most cases. The crushed area is divided with a straight fine-tipped scissors, and an antibiotic ointment is applied.

After the operation, it is critical that the caregivers separate the edges of the meatus and apply ointment twice a day for 2 weeks and then once a day for another 2 weeks to prevent one side of the meatotomy from adhering to the other side. Some medical professionals recommend dilation with a lubricated feeding tube or the tip of an ointment tube (antibiotic, steroid, or combination) for a period of up to 8 weeks. Some use topical application of steroid ointment or a combination of antibiotic and steroid ointment to decrease recurrence.

In a survey of office pediatric urologic procedures, which included meatotomy, lysis of labial adhesions, and newborn circumcision, Smith and Smith found that 95 of 99 parents stated that they were satisfied with their decision to have these procedures performed in the office, and 95% reported good outcomes (only one patient had recurrent meatal stenosis).[16]

Mild dysuria may occur after meatotomy, sometimes resulting in urinary retention. (See Complications.)

It is also important to note that spraying of the urine stream may occur for several days after surgical correction as a consequence of swelling. If stitches are used in a meatoplasty, urine spraying may persist until the stitches fully dissolve.

Depending on the age and temperament of the child, it may be preferable to perform meatotomy with the patient under sedation or general anesthesia in the operating room.

Some surgeons prefer meatoplasty, in which stitches are placed to help keep the meatus open, to meatotomy, citing research that suggests a lower recurrence rate after meatoplasty.[17]  Meatoplasty typically requires sedation or general anesthesia. Others have reported excellent results with meatotomy. Ultimately, the choice of approach (meatotomy, meatoplasty, or no surgery) is based on a thorough discussion among the provider, the family members, and the patient (if applicable).

After meatotomy, caregivers will typically be instructed to separate the edges of the meatus and apply antibiotic, steroid, or combination ointment twice a day for 2 weeks and then once a day for 2 more weeks. The physician may have other specific instructions, based on their usual care.

Complications include bleeding during or after meatotomy, infection (extremely rare) and recurrence. All of these complications are rare and typically respond readily to appropriate management.

Mild dysuria may be present for 1-2 days after meatotomy. If dysuria results in urinary retention, placing the child in a tub of warm water may stimulate micturition. Application of petroleum jelly or ointment to the meatus may decrease dysuria and the likelihood of retention. It can also be helpful to have the child void small amounts frequently rather than hold their urine for long periods of time.

In rare cases, a boy may develop a chronic inflammatory response that will be associated with some mild scabbing. This may require application of topical steroid or a redo procedure.

After meatotomy, caregivers should be instructed to dress the child in loose underwear for 24 hours. Activities, such as contact sports, bicycle rides, and playground activities, should be restricted for 3-4 days.

A systematic review and meta-analysis by Morris et al found that application of petroleum jelly to the glans after circumcision was associated with a reduction in the risk of meatal stenosis (relative risk, 0.024; 95% confidence interval, 0.0048-0.12).[4]

If the primary care physician is unwilling to perform a meatotomy, consultation with a pediatric urologist should be encouraged.

Typically, long-term follow-up by a specialist is not necessary; the vast majority of children do very well after surgical correction. Parents and patients should be aware of any changes in the urine stream that may indicate the rare recurrence of meatal stenosis.

If there are any questions or concerns, referral to a urologist should be made.