Optical Head-Mounted Display Technology for Low Vision Rehabilitation

Study Overview
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Brief Summary
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The goal of this study is to examine the ability of optical head-mounted display technology to enlarge the visual field of patients with severe visual field loss due to retinal dystrophy and to improve mobility and patient-reported outcomes.

Detailed Description
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Worldwide it is estimated that 191 million people have moderate to severe visual impairment (MSVI) and an additional 32.4 million are blind. Patients with uncorrectable MSVI may undergo low vision rehabilitation (LVR), which has been shown to improve functional abilities, such as mobility. However, existing LVR strategies do not adequately address severe visual field constriction. In this pilot study, the investigators will test the hypothesis that optical head-mounted display (HMD) technology expands constricted visual fields and improves mobility outcomes for patients with retinal dystrophy. We will use the Moverio HMD platform which is considered a non-significant risk device. Outcomes for patients with retinal dystrophy will be compared to normal age-matched controls.

Official Title
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Optical Head-Mounted Display Technology for Low Vision Rehabilitation

Conditions
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Retinal Dystrophies, Healthy

Intervention / Treatment
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* Device: Head-Mounted Display


Participation Criteria
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Eligibility Criteria
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Inclusion criteria for subjects with retinal dystrophy: diagnosis of retinal dystrophy severe vision loss that constitutes legal blindness able to perform a reliable Goldmann visual field test constricted visual field less than or equal to 20 degrees by Goldmann perimetry using the III4e stimulus in at least one eye with best-corrected visual acuity ≥ 20/60 Inclusion criteria for control subjects: healthy controls visit history with the Comprehensive and Pediatric Ophthalmology Services at the University of Michigan able to perform a reliable Goldmann visual field test Exclusion criteria for subjects with retinal dystrophy: movement disorder that precludes evaluation of mobility functional vision loss pregnant women Exclusion criteria for control subjects: visually significant ocular condition other than correctable refractive error movement disorder that precludes evaluation of mobility functional vision loss pregnant women

Ages Eligible for Study
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Minimum Age: 12 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Retinal Dystrophy<br>Subjects with retinal dystrophy will have their visual field, gait and self-reported mobility tested at baseline. Subjects will then be fit with a head-mounted display and undergo a brief training with the investigators to learn about use of the device. After a 2 week period of in-home adaptation to the device, their visual field, gait and self-reported mobility will be retested. | Device: Head-Mounted Display<br>* Head-mounted displays (HMD) are a class of technology that are worn on the user's head and project an image either in front of or into the eye.<br>* Other names: Epson Moverio;|
| Experimental: Healthy Age-Matched Controls<br>Age-matched control subjects without eye disease will have their visual field, gait and self-reported mobility tested at baseline. Control subjects will then be fit with a head-mounted display and undergo a brief training with the investigators to learn about use of the device. After a 2 week period of in-home adaptation to the device, their visual field, gait and self-reported mobility will be retested. | Device: Head-Mounted Display<br>* Head-mounted displays (HMD) are a class of technology that are worn on the user's head and project an image either in front of or into the eye.<br>* Other names: Epson Moverio;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the Planimetric Area of Goldmann Visual Field With the Use of Head-mounted Display Technology Compared to Baseline (Measured in Degrees Squared) | Using computer software we will calculate the area of participants' Goldmann visual fields in order to obtain a summary quantitative measurement of the extent of peripheral vision. Average of both eyes visual fields with intervention. | Baseline and two to four weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Gait Speed Compared to Baseline (Measured in Seconds) | Gait speed will be measured using an inertial measurement unit attached to participants' shoes and will quantify the time taken to move from the beginning to end of a short mobility course. Average of data from both feet with intervention. | Baseline and two to four weeks |