Is nasolacrimal duct obstruction (NLDO) common bilaterally?

Bilateral Nasolacrimal Duct Obstruction Prevalence

Bilateral nasolacrimal duct obstruction (NLDO) is less common than unilateral NLDO, occurring in approximately 40% of all NLDO cases, while unilateral cases account for about 60% of presentations.

Epidemiology and Prevalence

• Congenital nasolacrimal duct obstruction is one of the most frequently observed congenital abnormalities of the nose, with an overall incidence of 1 in 7000-8000 live births 1
• The ratio of bilateral to unilateral NLDO is approximately 40% to 60%, making bilateral cases less common than unilateral presentations 1
• Symptomatic NLDO occurs in approximately 5-6% of infants overall 2
• In studies examining treatment approaches, bilateral NLDO represented a smaller proportion of cases compared to unilateral obstruction 3

Clinical Characteristics of Bilateral NLDO

• Bilateral NLDO may be associated with other congenital abnormalities in up to 50% of cases, with this percentage increasing to 75% in bilateral manifestations 1
• The CHARGE syndrome (Coloboma, Heart defects, Atresia of the choanae, Retardation, Genital and Ear abnormalities) is the most frequent syndromal association, occurring in about 20% of cases 1
• Other associated malformations include meningoceles, hypertelorism, and clefts 1

Treatment Considerations for Bilateral NLDO

• Treatment success rates may differ between bilateral and unilateral cases:
  • In one study, children with bilateral NLDO had a 76% success rate with observation and deferred facility probing compared to 66% success with immediate office probing 3
  • This differs from unilateral cases, where immediate probing showed better success rates 4

Anatomical Considerations

• Patients with bilateral NLDO have been found to have a significantly higher rate of concomitant nasal pathologies requiring surgical intervention (78.6%) compared to unilateral NLDO patients (26.7%) 5
• These nasal abnormalities include septal deviation, concha bullosa, and inferior turbinate hypertrophy, which may contribute to the bilateral obstruction 5
• Septoplasty was required in 57.1% of bilateral NLDO cases versus only 16.7% in unilateral cases 5

Management Implications

• The higher prevalence of associated nasal abnormalities in bilateral NLDO suggests that comprehensive nasal evaluation is particularly important in these cases 5
• Treatment approaches may need to address both the nasolacrimal duct obstruction and any concomitant nasal pathology 5
• Spontaneous resolution can occur in bilateral cases, with one study showing resolution without surgery in both eyes for 56% of participants within 6 months of observation 3

Prognosis

• Late probing (after 15 months of age) for congenital NLDO showed a success rate of 83% in bilateral cases compared to 72% in unilateral cases 6
• The presence of bilateral disease may indicate more extensive anatomical issues that could affect long-term outcomes 5

In summary, while bilateral NLDO is less common than unilateral presentation, it is associated with a higher likelihood of concomitant nasal abnormalities and may be linked to syndromic conditions. This suggests that bilateral NLDO might represent a more complex anatomical or developmental issue rather than an isolated finding.