Dilated Versus Non-Dilated Wavefront Corrections for Patients With Down Syndrome

Study Summary

Individuals with Down syndrome (DS) live with visual deficits due, in part, to elevated levels of higher-order optical aberrations (HOA). HOAs are distortions/abnormalities in the structure of the refractive components of the eye (i.e. the cornea and the lens) that, if present, can result in poor quality focus on the retina, thus negatively impacting vision. HOAs in the general population are overall low, and thus not ordinarily considered during the eye examination and determination of refractive correction. However, for some populations, such as individuals with DS, HOAs are elevated, and thus the commonly used clinical techniques to determine refractive corrections may fall short. The most common clinical technique for refractive correction determination is subjective refraction whereby a clinician asks the patient to compare different lens options and select the lens that provides the best visual outcome. Given the cognitive demands of the standard subjective refraction technique, clinicians rely on objective clinical techniques to prescribe optical corrections for individuals with DS. This is problematic, because it may result in errors for eyes with elevated HOA given that these techniques do not include measurement of the HOAs. The proposed research evaluates the use of objective wavefront measurements that quantify the HOAs of the eye as a basis for refractive correction determination for patients with DS. The specific aim is to determine whether dilation of the eyes is needed prior to objective wavefront measurements. Dilation of the eyes increases the ability to measure the optical quality of the eye and paralyzes accommodation (the natural focusing mechanism of the eye), which could be beneficial in determining refractions. However, the use of dilation lengthens the process for determining prescriptions and may be less desirable for patients.

Primary Outcome

Distance (in LogMAR) visual acuity will be measured in the right eye with the British Standard Letter set or HOTV Matching for participants unable to name letters. Measurements will be obtained while the participant wears spectacle lenses based on their pre- and post-dilation refractions, respectively (from Visit 1). The order of testing is randomized. The primary outcome is the difference in distance visual acuity measurements calculated as visual acuity when wearing pre-dilation lens minus wea

Interventions

• DEVICE Dilated Refraction
• DEVICE Non-Dilated Refraction