Spectacles for Patients With Down Syndrome

Prescription spectacle lenses determined by clinically derived techniques. The specific techniques employed for each subject are left up to the masked examiner and are dependent upon the information needed for refraction determination, as well as ability of the participant to cooperate for testing. Measures may include autorefraction obtained pre or post dilation, retinoscopy obtained pre or post dilation, and subjective refraction obtained pre or post dilation.

Prescription spectacle lenses determined by metric-derived objective technique #1. For this method, wavefront error will be measured with the COAS (complete ophthalmic analysis system) wavefront aberrometer post-dilation with the goal of obtaining 3 to 5 high quality captures per eye. Wavefront measures will be re-sized to the patient's habitual pupil diameter and averaged. Post-measurement analysis will then be performed using a computer algorithm to identify the refractive correction predicted to produce the best image quality, as measured by maximization of the image quality metric Visual Strehl ratio in the spatial domain (VSX). The refractive correction determined from this analysis will be produced in prescription spectacle lenses and dispensed to the patient as the Intervention: Spectacles - Metric Technique #1 Derived.

Prescription spectacle lenses determined by metric-derived objective technique #2. For this method, wavefront error will be measured with the COAS (complete ophthalmic analysis system) wavefront aberrometer post-dilation with the goal of obtaining 3 to 5 high quality captures per eye. Wavefront measures will be re-sized to the patient's habitual pupil diameter and averaged. Post-measurement analysis will then be performed using a computer algorithm to identify the refractive correction predicted to produce the best image quality, as measured by maximization of the image quality metric Pupil Fraction tessellated (PFSt). The refractive correction determined from this analysis will be produced in prescription spectacle lenses and dispensed to the patient as the Intervention: Spectacles - Metric Technique #2 Derived.