Spectacles for Patients With Down Syndrome

Vision, Low Clinical Trial

Official title:

Identification of Optimum Spectacle Prescriptions for Patients With Down Syndrome

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03367793
• Other study ID #: EY024590
• Status: Completed
• Phase: N/A
• Start date: January 26, 2018
• Est. completion date: December 5, 2019

Study information

• Verified date: September 2021
• Source: University of Houston
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: December 5, 2019
• Est. primary completion date: June 10, 2019
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Diagnosis of Down syndrome

Exclusion Criteria:

• Nystagmus (Involuntary beating movement of the eyes)

• Visually significant media opacities (e.g. cataracts or corneal scars)

• Strabismic amblyopia (reduced vision in one eye related to a constant eye-turn)

• Anisometropic amblyopia (reduced vision in one eye related to a long-standing uncompensated difference in prescription between the two eyes)

Related Conditions & MeSH terms

• Down Syndrome
• Vision, Low

Intervention

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.
• 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.
• 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.

Locations

Country	Name	City	State
United States	University of Houston	Houston	Texas

Sponsors (1)

Lead Sponsor	Collaborator
University of Houston

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Adapted Visual Acuity	Aided LogMAR distance visual acuity obtained with either the British Standard Letters or HOTV - matching for subjects unable to name letters.	two months
Secondary	Initial Visual Acuity	Aided LogMAR distance visual acuity obtained with either the British Standard Letters or HOTV - matching for subjects unable to name letters.	1 day
Secondary	Spectacle Wear Time	Total wear time of each pair of spectacles as measured objectively by a temperature sensor data logger mounted to the spectacle temple.	two months
Secondary	Spectacle Assessment Survey Question 1	Participants were asked to select a face from a survey with five expressions (large frown, small frown, neutral, small smile, large smile) depicting their response to the question 'Do you like wearing this pair of glasses?' Responses were coded 1 through 5 with 5 = large smile.	two months
Secondary	Spectacle Assessment Survey Question 2	Participants were asked to select a face from a survey with five expressions (large frown, small frown, neutral, small smile, large smile) depicting their response to the question 'How well do you see with this pair of glasses when looking far away?' Responses were coded 1 through 5 with 5 = large smile.	two months
Secondary	Spectacle Assessment Survey Question 3	Participants were asked to select a face from a survey with five expressions (large frown, small frown, neutral, small smile, large smile) depicting their response to the question 'How well do you see with this pair of glasses when looking up close?' Responses were coded 1 through 5 with 5 = large smile.	two months