The Emmetropization Via Accommodation (EVA) - II Study

Uncorrected hyperopia (farsightedness) in children can lead to significant learning and visual problems, affecting their overall well-being and academic potential. Normally, infants are born with a moderate degree of hyperopia which should decrease as undergo a normal, developmental process called emmetropization, which mostly occurs during the first 18 months of life. Sometimes, this process fails, leaving children with higher-than-normal levels of hyperopia, which significantly increases their risk of developing conditions like strabismus (crossed eyes), amblyopia (lazy eye), and early literacy and scholastic issues. Infants who are at the greatest risk of not undergoing the normal emmetropization process are those with significantly higher levels of hyperopia early in infancy and those with poor ocular accommodation. The emmetropization process is not perfectly understood in human infants but may allow a window of opportunity for early intervention to help reduce the risk of debilitating vision conditions, while the visual system is still plastic. This study seeks to determine if early intervention, specifically partial refractive correction and visual engagement exercises (meant to stimulate ocular accommodation), can help improve the accommodative response and therefore reduce hyperopia in infants at high risk of not undergoing emmetropization. By treating 4-month-old infants with poor accommodation, the study aims to facilitate emmetropization and potentially reduce the risk of long-term visual problems. The study will also explore whether hyperopic defocus or accommodative effort is the primary signal guiding emmetropization, the two major theories of human emmetropization. Positive outcomes from this research could lead to new standards of care for hyperopic infants, potentially preventing a lifetime of vision-related issues and improving early literacy and academic performance.

Inclusion criteria

• Signed parental permission and HIPAA authorization and willingness to comply with study procedures.
• Infant 13-19 weeks of age at baseline.
• Either sex and any race or ethnicity.
• Good general health based on parent-provided history, normal pregnancy and delivery without serious complications, and birthweight >2500 g.
• Mean MEM accommodative lag >+1.25 D based on three measurements throughout the baseline examination.
• Cycloplegic spherical-equivalent hyperopia ≥+3.50 D in one or both eyes.

Exclusion criteria

• Astigmatism >2.00 D in either eye.
• Anisometropia >1.50 D spherical equivalent.
• Strabismus.
• Previous difficulty with pupil dilation.
• Cardiac, liver, asthma, or other respiratory disease.
• Ocular disease/abnormality, prior intraocular surgery, retinal detachment, optic nerve hypoplasia, malformation of the eye, cortical visual impairment, or active ocular inflammation.
• Hydrocephalus, Down syndrome, cerebral palsy, severe developmental delay, or seizure disorder.
• A condition preventing spectacle wear for the study duration (e.g., plagiocephaly).