Factors Associated with the Development of Strabismus in Children and Adolescents with Organic Ocular Diseases

ABSTRACT

PURPOSE: To evaluate risk factors associated with the development of strabismus in children with organic ocular diseases. METHODS: The authors reviewed the medical records of 143 patients diagnosed with organic ocular disease between the ages of six months and 19 years from March 2000 through September 2009. The distributions of etiology, age, visual acuity and visual acuity difference between both eyes at onset of visual loss, spherical equivalent difference between both eyes, duration of visual loss, and nystagmus were analyzed to determine relationships with the development of strabismus. RESULTS: Of 143 patients, strabismus developed in 41 children (28.7%). The causative diseases were congenital cataract (73.2%), developmental cataract (7.3%), uncorrected aphakia (7.3%), retinal detachment (4.9%), lens subluxation (2.4%), optic nerve disorder (2.4%), and corneal opacity (2.4%). The incidence of strabismus increased significantly in the cases of congenital disease, those < or = five years of the age at onset of visual loss, those with < or = 20/200 visual acuity, and those with large interocular spherical equivalent difference. There was no relationship between incidence of strabismus and visual acuity difference between both eyes. However, the incidence of strabismus increased significantly when the visual acuity difference was more than three Snellen lines in congenital ocular disease. CONCLUSIONS: When ocular disease is congenital, an increased risk of onset of strabismus should be considered when the age at onset of visual loss is less than five years, when visual acuity is below 20/200, and when there is a large spherical equivalent difference between both eyes.