How Should I Manage Congenital Nasolacrimal Duct Obstruction?
Tina
Rutar,
MD
At what age do you recommend probing? Do you recommend anesthesia? Does balloon dacryoplasty really work? When do you place stents?
First, are you convinced nasolacrimal duct obstruction (NLDO) is the cause of the infant’s symptoms? Chronic tearing in an infant can also be due to congenital glaucoma, corneal epithelial disease, chronic conjunctivitis, foreign body, eyelid malposition, trichiasis, or other congenital anomalies of the nasolacrimal system, such as punctal agenesis. Look for warning signs of congenital glaucoma, such as enlarged corneal diameters (> 12 mm horizontally in a 12-month-old), myopic refraction (against movement on the retinoscope), and optic disc cupping. Use the 20-D lens as a simple magnifier or a portable slit lamp to examine the anterior segment. The upper puncta are difficult to see in a squirmy infant, but the lower puncta should appear patent to visual inspection. The examination is easier if the infant is bottle feeding.
Congenital NLDO is typically caused by an imperforate valve of Hasner or stenosis of the nasolacrimal duct. It affects approximately 20% of infants. Most become symptomatic during the first month of life.1 Congenital NLDO presents as chronic tearing of one or both eyes associated with mucopurulent discharge. The involved side has an increased tear lake meniscus. The eyelashes are usually wet and matted. The skin of the lower eyelid may appear erythematous and, in more severe cases, shows superficial ulceration. Mucopurulent discharge can usually be expressed from the puncta with lacrimal sac massage. Typically, the conjunctivae are noninjected; however, chronic NLDO can rarely cause conjunctivitis. The lacrimal sac should be nontender and not erythematous—other-wise, suspect dacryocystitis. A bluish mass lying below the medial canthal tendon is likely a dacryocystocele. To confirm the diagnosis of NLDO, perform a modified dye disappearance test (Figure 36-1). Instill fluorescein in the lower conjunctival fornix in each eye and examine the tear lake with a blue light filter 5 minutes later. You can illuminate both eyes with blue light from a distance using the slit lamp or a portable blue penlight while the infant sits in the caregiver’s arms. The fluorescein should have disappeared or nearly disappeared from the tear lakes. Failure to see this is usually sufficient to confirm the diagnosis.
Figure 36-1. A 15-month-old boy with an increased tear lake meniscus in the left eye due to nasolacrimal duct obstruction (A). After 5 minutes, fluorescein dye has disappeared from the right eye but not from the left eye (B).
Discussion with the caregiver regarding treatment or observation should take into consideration the age of the infant at presentation. In the first year of life, more than 90% of cases resolve spontaneously. For infants who are still symptomatic at 12 months of life, the likelihood of spontaneous resolution by the second year of life is still 60%.1 However, several retrospective studies found that the success rate of probing as a primary procedure for congenital NLDO decreased with age. For example, Katowitz and Welsh found a cure rate of 98% for children < 6 months of age, 77% for 13 to 18 months of age, and 33% for > 24 months of age.2 Thus, they advocated probing before 13 months of age. Contradictory to this, an age effect was not found in a more recent multicenter prospective trial.3 Probing was successful 78% of the time in the 6- to < 36-month age group, regardless of age. The findings of the older retrospective trials may be due to differences in populations selected for treatment at different ages.
My recommendation is for initial probing somewhere between 12 and 24 months of age. Delaying probing until at least 12 months is prudent, given its high success rate even after age 12 months and the high rate of spontaneous resolution during the first 12 months. Keep in mind that some will need treatment earlier. Reasons to probe sooner include caregiver request due to the infant’s symptoms and the uncommon, but serious, complication of dacryocystitis. Nasal mucoceles, which may interfere with breathing when bilateral, may also necessitate early intervention.
One argument often made for early probing is the avoidance of anesthesia. In-office probing is impractical for children over the age of 8 months. Papoosing or restraining the head of a 4- to 6-month-old infant is relatively straightforward, whereas restraining a 12-month-old would be extremely stressful on the child, parent, and physician. Analyses performed in the mid-1990s found that in-office probing at 6 months was significantly more cost effective than in-hospital probing at 12 months, accounting for a 70% chance of spontaneous resolution between 6 and 12 months and for the necessity to perform in-hospital probings for failed office probings.4 However, these analyses did not place a cost on the discomfort and possible complications of treatment for infants who would otherwise spontaneously resolve. Because office probing is performed under less controlled conditions and on immature tissues, it may have a slightly higher risk of iatrogenic damage to the lacrimal system with formation of false passages than in-hospital probing. Also consider your own comfort, the availability of pediatric anesthesia, and the time required for a procedure under general anesthesia. All considered, it is my practice to perform probings with anesthesia.
Probing can be combined with placement of either a monocanalicular or a bicanalicular stent.5 Monocanalicular stents have the advantage of not requiring intraoperative retrieval from the nose, which will be appreciated by anyone who has struggled to recover silicone tubes from under the inferior turbinate in a tiny nose. There are also new bicanalicular intubation systems (such as the Ritleng, FCI Ophthalmics, Marshfield Hills, MA) that facilitate removal from the nose. Given the high success rate of simple probing and the cumbersomeness of removing stents in small children, I use them in patients who have failed simple probing, or in patients with Down syndrome or craniofacial anomalies, who may have more complex disorders of lacrimal drainage anatomy. I leave stents in place for 2 to 4 months.
I am often asked about balloon catheter dacryoplasty, which combines simple probing with mechanical dilation of the nasolacrimal duct (Figure 36-2).6 This is accomplished by inflating and subsequently deflating a balloon that surrounds the distal probe. Balloon dacryoplasty has not been studied head-to-head against simple probing or probing with intubation. Another consideration is the cost of balloon catheter dilation. The surgical facility cost is approximately $300 for a unilateral procedure and $555 for a bilateral procedure. Given the lack of good evidence to support or refute balloon dacryoplasty, I reserve it for patients who have failed simple probing. What effect, if any, it has beyond simple probing remains to be determined.
Figure 36-2. Balloon catheter dacryoplasty. A balloon fitted onto the end of a catheter (A) is placed into the nasolacrimal duct (B) and inflated repeatedly to varying degrees of pressure, as measured by the accompanying gauge (C).
In summary, for primary procedures, probing is a great starting point because it is the least expensive and time intensive. Unless forced to intervene at an earlier age, I perform probings after 1 year of age, under anesthesia. If simple probing fails, alternatives include repeat probing, balloon dacryoplasty, or probing with stenting. My personal preference is probing with dacryoplasty or probing with stent placement, rather than repeat probing alone. Dacryocystorhinostomy is reserved for patients with multiple treatment failures.
References
1. MacEwen CJ, Young JD. Epiphora during the first year of life. Eye. 1991;5(Pt 5):596-600.
2. Katowitz JA, Welsh MG. Timing of initial probing and irrigation in congenital nasolacrimal duct obstruction. Ophthalmology. 1987;94(6):698-705.
3. Repka MX, Chandler DL, Beck RW, et al. Primary treatment of nasolacrimal duct obstruction with probing in children younger than 4 years. Ophthalmology. 2008;115(3):577-584.
4. Kassoff J, Meyer DR. Early office-based vs late hospital-based nasolacrimal duct probing: a clinical decision analysis. Arch Ophthalmol. 1995;113(9):1168-1171.
5. Repka MX, Melia BM, Beck RW, et al. Primary treatment of NLDO with nasolacrimal duct intubation in children younger than 4 years of age. J AAPOS. 2008;12(5):445-450.
6. Repka MX, Melia BM, Beck RW, et al. Primary treatment of nasolacrimal duct obstruction with balloon catheter dilation in children younger than 4 years of age. J AAPOS. 2008;12(5):451-455.