Unilateral congenital nasolacrimal duct obstruction and amblyopia risk factors

INTRODUCTION: This study aimed to investigate the prevalence of amblyopia risk factors in patients with unilateral congenital nasolacrimal duct obstruction (CNLDO). PATIENTS AND METHODS: A retrospective interventional case series was performed on all consecutive patients of unilateral CNLDO who underwent probing over a 6-month period in 2017. All patients underwent a complete ocular examination, retinoscopy, axial length measurements and keratometry. Risk factors for amblyopia were noted based on the American Association for Pediatric Ophthalmology and Strabismus guidelines. The fellow eye of the patients with CNLDO was taken as an internal control. Statistical analysis was performed using Stata version 13.0 statistical software. A p-value of ≤0.05 was considered statistically significant. RESULTS: One hundred eyes of 50 patients were studied. The median age at presentation was 36 months without any gender predisposition (M: 26, F: 24). All patients presented with symptoms of epiphora. Seven (14%) of the patients were noted to have amblyopia risk factors: five (10%) were secondary to refractive errors and two (4%) had congenital cataracts. The anisometropia noted in the five patients showed the worse eye to be the one with CNLDO in all the cases. The common refractive error noted was a compound hyperopic astigmatism in three eyes followed by mixed astigmatism and simple hyperopia in one eye each. CONCLUSION: The prevalence of amblyopia risk factors in children with unilateral CNLDO is marginally higher than that reported in general population. Hence, a thorough evaluation should be carried out to detect amblyopia risk factors and for their prompt management.