The Infant Aphakia Treatment Study

Abstract

Objective-To compare contact lenses and intraocular lenses (IOLs) for the optical correction of unilateral aphakia during infancy.Methods-In a randomized, multicenter (12 sites) clinical trial, 114 infants with a unilateral congenital cataract were assigned to undergo cataract surgery either with or without IOL implantation. Children randomized to IOL treatment had their residual refractive error corrected with spectacles. Children randomized to no IOL had their aphakia treated with a contact lens Main Outcome Measures-Grating acuity at 12 months of age and HOTV visual acuity at 4.5 years of age Results-Enrollment began in December 2004 and was completed in January 2009. The median age at the time of cataract surgery was 1.8 months. Fifty patients were 4-6 weeks of age at the time of enrollment, 32 patients were between 49 days and 3 months of age and the remaining 32 children were 3 to 7 months of age. Fifty-seven children were randomized to each treatment group with either IOL placement or aphakia. The eyes with cataracts had shorter axial lengths and steeper corneas on average than the fellow eyes.Conclusions-The optimal optical treatment of aphakia in infants is unknown. IATS was designed to provide empirical evidence whether optical treatment with an IOL or a contact lens following unilateral cataract surgery during infancy is associated with a better visual outcome.

Predictability of Intraocular Lens Power Calculation Formulae in Infantile Eyes With Unilateral Congenital Cataract: Results from the Infant Aphakia Treatment Study

“…1 Infants with a unilateral visually significant cataract (≥3 mm central opacity) and an age of 28 to 209 days at the time of cataract surgery were eligible for enrollment in the study. The main exclusion criteria were persistent fetal vasculature associated with stretching of ciliary processes or involvement of the optic nerve or retina, corneal diameter less than 9 mm, premature birth (<36 weeks gestational age), presence of a medical condition that may interfere with later visual acuity testing, or acquired cataract.…”

“…1 Retinoscopy was performed under cycloplegia to determine residual refractive error at the 1-month postoperative examination. This measure was converted to spherical equivalent (half of the cylinder added to the sphere) and was compared with the predicted refraction.…”

“…The Infant Aphakia Treatment Study was a multi-center, randomized, controlled clinical trial sponsored by the National Eye Institute to determine whether primary IOL implantation in infants younger than 7 months of age with a unilateral congenital cataract results in improved visual outcomes over contact lens correction of aphakia. 1,2 Half of the 114 infants enrolled in this multicenter study were randomized to receive an IOL with a lens power determined using the Holladay 1 formula. The mean absolute prediction error was 1.8 ± 1.3 diopters (D), with greater error noted in eyes with shorter globe axial length (AL).…”

Association of Contact Lens Adherence With Visual Outcome in the Infant Aphakia Treatment Study

“…1 The IATS is a multicenter randomized clinical trial comparing IOL and contact lens treatment after unilateral congenital cataract surgery in children 6 months of age or younger who were born from August 1, 2004 through December 31, 2008. Data analysis was performed from August 9, 2016 to August 6, 2017.…”

“…1 Children who were randomized to aphakia were treated with a contact lens. At age 4.5 years, about 20% of treated eyes had visual acuity of 20/32 or better, 30% had 20/40 to 20/100 acuity and 50% had 20/200 or worse acuity.…”