Etiology
- Most common is membranous obstruction at valve of Hasner in distal nasolacrimal duct (NLD)
- Narrowing of proximal NLD
- Occlusion or absence of punctum
- Malformation of the lacrimal duct opening
- Canalicular obstruction
- Congenital
- After HSV or EKC infection
- Traumatic
Epidemiology
- 50% of newborns have valve of Hasner obstruction
- 5–15% of infants have clinical NLDO
- One-third of cases bilateral
- Males and females equally affected
History
- Tearing and discharge, commonly presenting within first month of life
- Discharge accumulates with sleep
- Symptoms worse with URI or outside in cold, windy weather
- Tearing with mucopurulent discharge usually indicates distal obstruction; tearing without discharge usually indicates proximal ductal stenosis.
- Question caretaker about conjunctival injection, photophobia, history of allergy/atopy.
- Other pertinent questions: Daily or intermittent symptoms? Improving or worsening during first year?
- Less common presentations
- Onset after first year of life
- After HSV or EKC infection
- Dacryocystocele
- Due to trauma of the nasolacrimal system
Clinical features
- Excess tear film and mucous discharge
- Quiet eyelids and conjunctiva indicating no infectious etiology, especially important in first week of life
- Reflux from NL sac with digital pressure
- Evaluate for trichiasis, epiblepharon.
- Evaluate for signs of glaucoma.
- Look for open punctum on each eyelid (portable slit lamp or 20 D lens).
Dye disappearance testing (Figure 1) is helpful to confirm the diagnosis, but a crying infant can confound results. On testing, when fluorescein is visible in the nostril and patient is still symptomatic this might suggest NLD stenosis severe enough to cause symptoms; however, an alternative diagnosis should be sought.
Less common findings:
- Duplicate puncta
- NLD system fistula: Can be patent (Figure 2)
- Dacryocystocele/dacryocystitis:
- Accumulation of mucous in NL sac from distal valve of Hasner obstruction and unusually competent proximal valve of Rosenmuller
- Blue discoloration in medial canthus region, inferior to medial canthal tendon (Figure 3), often is seen at birth and is usually due to amniotic fluid accumulation (amniotocele).
- Female incidence twice as high as male
- Infectious dacryocystitis possible consequence — about 50% on presentation
- Question caretakers about difficulty feeding.
- Can be associated intranasal cysts — about 25% (Figure 4)
- Can be bilateral > 25% of cases
- More urgent evaluation and treatment needed
Figure 1. Primary dye disappearance test on right-sided NLDO. (Courtesy Oculoplastic Surgery Unit, Fuenlabraden Hospital, Madrid).
Figure 2. Nasolacrimal fistula. (Courtesy Journal of Korean Ophthalmologic Society 2013;54:11).
Figure 3. Right congenital dacryocystocele (EyeRounds Online Atlas of Ophthalmology) and left congenital dacryocystocele with dacryocystitis.
Figure 4. Nasal cyst associated with dacryocystocele. Open Journal of Pediatrics 2012:2(2).