Anisometropia and Amblyopia Outcomes in Early Versus Late Resolution of Congenital Nasolacrimal Duct Obstruction in Older Infants

Congenital nasolacrimal duct obstruction is a known risk factor for amblyopia and anisometropia. The purpose of this study was to investigate whether the rate of anisometropia and amblyopia development differed based on the age at CNLDO resolution in older infants. This retrospective chart review at a single tertiary children’s hospital from 2007 to 2017 compared early versus late spontaneous resolution (cutoff 12 months) and intervention (cutoff 15 months) groups presenting at ≥9 months of age, comparing visual outcomes, including anisometropia (≥1 D of sphere or cylinder) and amblyopia (≥2 levels difference in Teller acuity or optotype testing). Parents/guardians were contacted by phone for missing data on spontaneous resolution or intervention status. A total of 462 patients were included (152 early; 310 late group). The early group presented at a median age of 12.0 (interquartile range: 10.0, 13.0) months, while the late group presented at 21.0 (interquartile range: 15.0, 32.0) months. Unilateral disease occurred in 62% and 59%, respectively. Anisometropia was seen in (12/102) 12% of early versus (25/243) 10% of late patients (p = 0.686, 95% CI: –0.059, 0.088), and amblyopia in (4/131) 3% of early versus (14/286) 5% of late patients (p = 0.322, 95% CI: –0.061, 0.018). In patients presenting <24 months without undergoing surgery, spontaneous resolution occurred in 76% between 12 and 24 months (n = 41). Anisometropia and amblyopia rates did not significantly differ between early and delayed intervention for congenital nasolacrimal duct obstruction in this retrospective cohort presenting beyond 9 months of age to a children’s hospital. This study found frequent late spontaneous resolution.