Adherence to Occlusion Therapy in the First Six Months of Follow-Up and Visual Acuity among Participants in the Infant Aphakia Treatment Study (IATS)

Abstract

Achieving good vision in infants born with a unilateral cataract is believed to require early surgery and consistent occlusion of the fellow eye. This article examines the relationship between adherence to patching and grating acuity. Data came from the Infant Aphakia Treatment Study, a randomized clinical trial of treatment for unilateral congenital cataract. Infants were either left aphakic (n = 53) or had an intraocular lens implanted (n = 55). Patching was prescribed 1 hour per day per month of age until 8 months of age and 50% of waking hours thereafter. Adherence was measured as the mean percentage of prescribed patching reported in a 7-day diary completed 2 months after surgery, and 48-hour recall interviews conducted 3 and 6 months after surgery. Grating visual acuity was measured within 1 month of the infant's first birthday (n = 108) using Teller Acuity Cards by a tester masked to treatment. Nonparametric correlations were used to examine the relationship with grating acuity. On average, caregivers reported patching 84.3% (SD = 31.2%) of prescribed time and adherence did not differ by treatment (t = -1.40, df = 106, p = 0.16). Adherence was associated with grating acuity (r(Spearman) = -0.27, p < 0.01), but more so among pseudophakic (r(Spearman) = -0.41, p < 0.01) than aphakic infants (r(Spearman) = -0.10, p = 0.49). This study empirically has shown that adherence to patching during the first 6 months after surgery is associated with better grating visual acuity at 12 months of age after treatment for unilateral cataract and that implanting an intraocular lens is not associated with adherence. (ClinicalTrials.gov number, NCT00212134.).