NCT03367793

Spectacles for Patients With Down Syndrome

Identification of Optimum Spectacle Prescriptions for Patients With Down Syndrome

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (actual)
• Sponsor: University of Houston · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This study tests the hypothesis that objectively derived spectacle prescriptions based on wavefront aberration measurements of the eyes of individuals with Down syndrome can provide an improvement in visual acuity over that obtained with spectacle prescriptions based on standard clinical prescribing techniques. The objectively derived prescriptions are derived using strategies to optimize retinal image quality as measured by image quality metrics, and thus these prescriptions will be referred to as metric-derived.

Detailed description

Individuals with Down syndrome suffer from significant ocular complications including high levels of lower-order refractive error (sphere and cylinder) and elevated levels of higher-order aberrations. These optical factors likely contribute to the poor acuity observed in this population. Current clinical prescribing practices may under-serve this community, as the cognitive demands of the subjective refraction sequence are difficult for this population and often leave clinicians to prescribe from objective clinical findings that target full correction of sphero-cylindrical refractive error. This prescribing practice can lead to sub-par outcomes given the fact that full lower-order corrections can exacerbate the effects of higher-order aberrations in more aberrated eyes. For this study, individuals with Down syndrome will be dispensed three pairs of spectacles for 2 months each, in random order: one clinically-derived, and two objectively-derived refractions based upon methods designed to optimize a given metric of retinal image quality which takes into consideration the wavefront aberration measurements of the eye. Both initial and adapted visual acuity in the presence of each correction will be evaluated to determine whether the objectively-derived refractions outperform clinically-derived refractions.

Conditions

• Vision, Low

Interventions

Type	Name	Description
DEVICE	Spectacles - Clinically Derived	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.
DEVICE	Spectacles - Metric Technique #1 Derived	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.
DEVICE	Spectacles - Metric Technique #2 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.

Timeline

• Start date: 2018-01-26
• Primary completion: 2019-06-10
• Completion: 2019-12-05
• First posted: 2017-12-11
• Last updated: 2021-10-25
• Results posted: 2021-10-25

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated device study