Healthy, Retinal Dystrophies
Conditions
Brief summary
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
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.
Interventions
DEVICEHead-Mounted Display
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.
Sponsors
University of Michigan
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
12 Years to No maximum
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in the Planimetric Area of Goldmann Visual Field With the Use of Head-mounted Display Technology Compared to Baseline (Measured in Degrees Squared) | Baseline and two to four weeks | 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. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Gait Speed Compared to Baseline (Measured in Seconds) | Baseline and two to four weeks | 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. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Retinal Dystrophy 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.
Head-Mounted Display: 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. | 10 |
| Healthy Age-Matched Controls 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.
Head-Mounted Display: 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. | 10 |
| Total | 20 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | incomplete data | 2 | 0 |
Baseline characteristics
| Characteristic | Retinal Dystrophy | Healthy Age-Matched Controls | Total |
|---|---|---|---|
| Age, Continuous | 33.5 years | 33 years | 33.5 years |
| Gait Speed | 1.27 meters per second | 1.25 meters per second | 1.26 meters per second |
| Race and Ethnicity Not Collected | — | — | 0 Participants |
| Sex: Female, Male Female | 5 Participants | 5 Participants | 10 Participants |
| Sex: Female, Male Male | 5 Participants | 5 Participants | 10 Participants |
| Visual Field Area | 568.96 degrees^2 | 19280.09 degrees^2 | 19009.42 degrees^2 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 12 | 0 / 10 |
| other Total, other adverse events | 0 / 12 | 0 / 10 |
| serious Total, serious adverse events | 0 / 12 | 0 / 10 |
Outcome results
Primary
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.
Time frame: Baseline and two to four weeks
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Retinal Dystrophy | Change in the Planimetric Area of Goldmann Visual Field With the Use of Head-mounted Display Technology Compared to Baseline (Measured in Degrees Squared) | 563.08 degrees^2 |
| Healthy Age-Matched Controls | Change in the Planimetric Area of Goldmann Visual Field With the Use of Head-mounted Display Technology Compared to Baseline (Measured in Degrees Squared) | -3799.19 degrees^2 |
Comparison: Test of equivalence of visual field area at baseline.p-value: 0.0001Wilcoxon (Mann-Whitney)
Comparison: Test of equivalence of visual field area under intervention conditions.p-value: 0.0001Wilcoxon (Mann-Whitney)
Comparison: Comparison between study arms of the change in the visual field area (average of both eyes) detected between baseline and intervention.p-value: 0.003Wilcoxon (Mann-Whitney)
Secondary
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.
Time frame: Baseline and two to four weeks
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Retinal Dystrophy | Change in Gait Speed Compared to Baseline (Measured in Seconds) | -.01 meters per second |
| Healthy Age-Matched Controls | Change in Gait Speed Compared to Baseline (Measured in Seconds) | -.01 meters per second |
Comparison: Test of equivalence of gait speed at baseline.p-value: 0.38Wilcoxon (Mann-Whitney)
Comparison: Test of equivalence of gait speed under intervention conditions.p-value: 0.27Wilcoxon (Mann-Whitney)
Comparison: Comparison between study arms of the change in the gait speed detected between baseline and intervention.p-value: 0.79Wilcoxon (Mann-Whitney)