Abstract
Abstract: :
Purpose: To evaluate the relationship between electrophysiological retinal abnormalities in children referred for investigation of suspected reduced vision and refractive error. Methods: The group studied were 123 consecutive patients referred over a 14 month period from the Paediatric service of Moorfields Eye Hospital for electrophysiological investigation of reduced vision. Subjects were divided into 5 refractive categories according to their spectacle correction: high myopia (<=-6D), low myopia (>-6D and <-0.75D), emmetropia (>-0.75 and <1.5D), low hyperopia (>1.5 and < 6D) and high hyperopia (>6D). Patients with a known diagnosis at the time of electrophysiological testing were excluded. Only the first member of any one family was included if more than one sibling had been tested. All tests were performed to incorporate ISCEV standards, using gold fold corneal electrodes where possible. In younger patients skin electrodes and an abbreviated protocol were employed. Results: The mean age of patients was 7.1 years with an overall incidence of abnormal electrophysiological findings of 31%. The incidence of abnormality was higher in high ametropes (13/25, 52%) as compared to the other groups (25/98, 25.5%). This difference was statistically significant (Chi-Squared, p = 0.01). The odds ratio for retinal abnormalities in high ametropes as compared to low ametropes and emmetropes was 3.16 (95% CI 1.28-7.83). There was no significant variation in frequency of abnormalities between low myopes, emmetropes and low hyperopes. The rate of abnormalities was very similar in both high myopes (8/15) and high hyperopes (5/10). Conclusions: High ametropia in children being investigated for poor vision is associated with a high rate of retinal electrophysiological abnormalities. This association is not found at low refractive errors. This is compatible with the hypothesis that there is a developmental association between normal retinal function and emmetropia. Electrophysiological testing should be considered in cases of high ametropia in childhood to rule out associated retinal pathology.
Keywords: electroretinography: clinical • refractive error development • retinal degenerations: hereditary