title: Comparison of Anisometropia and Refractive Status in Children With Unilateral and Bilateral Congenital Nasolacrimal Duct Obstruction.
abstract: OBJECTIVE
  To evaluate and compare the refractive state in children diagnosed as having unilateral or bilateral congenital nasolacrimal duct obstruction (CNLDO). This study also compares how the laterality of CNLDO affects the refractive state of the patients.
  
  
  METHODS
  This descriptive cross-sectional study includes consecutive children with unilateral and bilateral CNLDO over a period of 1 year. Cycloplegic refraction was performed on each child who presented with CNLDO followed by appropriate plans for treatment. The refractive errors of patients with unilateral and bilateral CNLDO were compared.
  
  
  RESULTS
  One hundred sixty-one patients with unilateral CNLDO (mean age: 29 ± 19.93 months) and 46 with bilateral CNLDO (mean age: 30 ± 16.21 months) were enrolled from August 2013 to July 2014. The rate of the anisometropia (≥ 1 diopters [D] difference between the two eyes) was 13.7% (n = 22) and 8.6% (n = 4) in patients with unilateral and bilateral CNLDO, respectively. Interocular difference was significant in terms of spherical equivalent (P < .01) but not cylindrical refractive error in patients with unilateral CNLDO. Patients with bilateral CNLDO had insignificant interocular differences in terms of spherical equivalent and cylindrical refractive errors (P > .05).
  
  
  CONCLUSIONS
  Unilateral CNLDO is associated with statistically significant anisometropia compared to bilateral CNLDO, which predisposes children with unilateral CNLDO to amblyopia. It is vital to perform cycloplegic refraction routinely and counsel parents regarding regular follow-ups. [J Pediatr Ophthalmol Strabismus. 2016;53(3):168-172.].
authors.forename: Sorath Noorani
authors.initials: SN
authors.lastname: Siddiqui
authors.forename: Hassan
authors.initials: H
authors.lastname: Mansoor
authors.forename: Muhammad
authors.initials: M
authors.lastname: Asif
authors.forename: Umair
authors.initials: U
authors.lastname: Wakeel
authors.forename: Adnan Aslam
authors.initials: AA
authors.lastname: Saleem
mesh_terms: D000550:Amblyopia / Q000503:physiopathology; D015858:Anisometropia / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D006801:Humans; D007223:Infant; D007767:Lacrimal Duct Obstruction / Q000151:congenital / Q000503:physiopathology*; D009301:Nasolacrimal Duct / Q000503:physiopathology*; D012029:Refraction, Ocular / Q000502:physiology*