Observations on the development and progression of unilateral high myopia

The purpose of this article is to document the rare observation of the development, progression, retinal changes, and results of visual rehabilitation in a young child with unilateral high myopia, as well as additional clinical observations in four very young patients with this condition. We also examine the role of factors such as amount of astigmatism, presence of strabismus, degree of anisometropia, and penalization in the development of optimal vision in these patients.

A review of patients from 1997-2002 disclosed 33 individuals with a diagnosis of unilateral high myopia. Five children with adequate information on the progression of myopia and/or in whom a final visual outcome could be determined were included in this study. We excluded patients with insufficient follow-up, those who did not comply with occlusion, and those with co-existing ocular conditions such as retinopathy of prematurity.

Three females and two males (four right eyes and one left) were followed for a period of 16 months to 7 years. Myopic fundus changes were present in three patients. Glasses were the preferred method of optical correction in four patients; one patient was prescribed a contact lens. Occlusion therapy was used in four of the five patients. Strabismus was present in four. Ipsilateral astigmatism of +2.00 D or more was present in three of the affected eyes. The difference in the spherical equivalent refraction between both eyes in each patient ranged from 5 to 20 diopters. In one patient, we observed the progressive development of unilateral myopia from an initial hypermetropia of +2.00 at age 2 months to myopia of -9.00 at the age of 5 years.

Unilateral high myopia is probably not present at birth. Our observations support its development in the first few years of life. The results of amblyopia therapy depend on the degree of anisometropia, the co-existence of strabismus, the compliance with penalization, and the presence of retinal abnormalities.