Observational Study to Assess the Reliability and Validity of the MLYMT and MLSDT

Study Overview
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Brief Summary
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This is a prospective Multi-Center Observational Study to assess the reliability and validity of the Multi-Luminance Y-Mobility Test (MLYMT) and Multi-Luminance Shape Discrimination Study (MLSDT) Main Outcome Measures: (i) Performance scores in normal and severely visually impaired subjects with a clinical diagnosis of retinitis pigmentosa (RP) on MLYMT and MLSDT at multiple luminance levels and (ii) reliability and content validity of MLYMT and MLSDT.

Detailed Description
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Two assessment visits will be conducted in order to evaluate functional visual performance in severely vision impaired subjects with RP and normally sighted subjects. Two visits will occur at week 0 and week 4 with functional vision assessments occurring at both visits in order to assess visit-to-visit variability. For the MLYMT, navigational vision will be assessed using each eye and binocularly at up to 6 different light levels (range 0.3 to 100 lux). Subjects will also perform the Multi-Luminance Shape Discrimination Test (MLSDT) which assesses near object recognition under different lighting levels. MLYMT and MLSDT performance will be evaluated together with Best Corrected Visual Acuity (BCVA), Visual Field (VF) and responses to visual function questionnaires. Subjects will be assigned to one of two cohorts based on presence or absence of RP in addition to BCVA performance.

Official Title
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A Prospective Multi-Center Observational Study to Assess the Reliability and Validity of the Multi-Luminance Y-Mobility Test (MLYMT) and Multi-Luminance Shape Discrimination Test (MLSDT)

Conditions
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Retinitis Pigmentosa, Retinal Dystrophy

Intervention / Treatment
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* Other: Observational


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Able to comprehend and give informed consent. Able to comply with testing and all protocol tests. Eligible for 1 of 2 cohorts listed below: Cohort 1: Normally Sighted Participants with clinically normal ocular findings and BCVA better than logMAR 0.3 (as confirmed by ETDRS letter score > 73) in each eye Cohort 2: Severely Sight Impaired Participants with BCVA no better than logMAR 1.6 in better seeing eye, and worse than LogMAR 1.9 in the worse seeing eye, and a clinical diagnosis of advanced RP Exclusion Criteria: Concurrent participation in any interventional clinical trial or receipt of an investigational drug within the previous 6 months Presence of any condition other than RP Disease that impairs visual acuity or visual fields e.g., visually significant cataract or visual field loss in glaucoma Presence of neurological condition that impairs visual acuity or visual field, e.g., hemianopia secondary to stroke Individuals who refuse or are incapable of performing mobility testing Individuals with retinal prosthesis (such as ARGUS-II) Participation in Nanoscope studies NTXMCO-002 (RESTORE) or NTXMCO-004 (STARLIGHT)

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Normally Sighted<br>Participants with clinically normal ocular findings and BCVA better than logMAR 0.3 in each eye. | Other: Observational<br>* The goal of this observational study is to assess the reliability and validity of the multi-luminance Y-Mobility Test (MLYMT) and multi-luminance shape description test (MLSDT) for evaluation of subjects with severe vision impairment due to RP. Normally sighted subjects will provide a control group. The MLYMT consists of two LED panels, one of which is illuminated at multiple luminance levels, positioned at the end of Y-configuration. Seven obstacles are placed ahead of the panels, which the test subject should detect and avoid before reaching and touching the lit panel.<br>|
| Severely Sight Impaired<br>Participants with BCVA no better than logMAR 1.6 in better seeing eye, and worse than logMAR 1.9 in the worse seeing eye, and a clinical diagnosis of advanced RP | Other: Observational<br>* The goal of this observational study is to assess the reliability and validity of the multi-luminance Y-Mobility Test (MLYMT) and multi-luminance shape description test (MLSDT) for evaluation of subjects with severe vision impairment due to RP. Normally sighted subjects will provide a control group. The MLYMT consists of two LED panels, one of which is illuminated at multiple luminance levels, positioned at the end of Y-configuration. Seven obstacles are placed ahead of the panels, which the test subject should detect and avoid before reaching and touching the lit panel.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| MLYMT scores in normal and severely visually impaired subjects with a clinical diagnosis of RP on MLYMT | A higher MLYMT score (range -1 to 5) indicates better navigational vision. | 4 Weeks | 
| MLSDT scores in normal and severely visually impaired subjects with a clinical diagnosis of RP on MLSDT | A higher MLSDT score (range 0 to 5) indicates greater shape discrimination ability at lower luminance level | 4 Weeks | 
| Reliability and construct validity of MLYMT | Evaluation of the performance (test-retest reliability) of the test(s) based on the visual acuity | 4 Weeks | 
| Reliability and construct validity of MLSDT | Evaluation of the performance (test-retest reliability) of the test(s) based on the visual acuity | 4 Weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Retinitis Pigmentosa, Inherited Retinal Diseases, Eye Diseases, Retinal Degeneration, Mobility Test, Multi-luminance Y- Mobility Test