Multiplexing Prism Fitting for Field Expansion of Monocular Vision

Study Overview
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Brief Summary
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The investigators are developing an assistive device, known as multiplexing prism that expands the field of view for individuals with acquired monocular vision (loss of an eye). The investigators are testing a simplified design and fitting protocol to provide field expansion for individuals with acquired monocular vision.

Official Title
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Monocular Visual Confusion for Field Expansion

Conditions
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One Eye Blindness, Blind Left Eye, Blind Right Eye

Intervention / Treatment
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* Device: Multiplexing Prism


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: No medical health issues such as seizures, motor movements problem Loss of vision in one eye (no light perception/enucleation/evisceration) for >1 year Visual acuity of the seeing eye: Better than 20/32 visual acuity with correction No visual field defect in the seeing eye (nasal field of at least >45degree) No medical health issues such as seizures, motor movements problem Exclusion Criteria: Patients with any physical or mental disabilities, including cognitive dysfunction, balance problems, or other deficits that could impair their ability to respond to the stimuli presented in this study will be excluded Any person with motor movements problem (e.g., unable to use extremities)

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Device Feasibility
Intervention Model: Single Group Assignment
Interventional Model Description: Individuals with Acquired Monocular Vision/ Blindness in One Eye
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Field Expansion<br>Field of view on the nasal side (same side as the blind eye) with and without multiplexing prism | Device: Multiplexing Prism<br>* Multiplexing prism is designed for spatial vision multiplexing. It allows partial light transmission through the prism allow the observer to simultaneously see the physical world through the prism and see the shifted view from the non-seeing side. It is developed to expand the field of view of individuals with just one eye.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Field expansion from multiplexing prism | Field expansion based on the maximum field of view on the nasal side (same side as the blind eye) with and without multiplexing prism. If the nasal field with multiplexing prism is larger than without prism, there is a gain in field expansion. | Approximately 2 sessions, up to 3 hours for each session, any time within 2 month period | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum extent of nasal visual field with multiplexing prism | The farthest nasal field of view with multiplexing prism | Approximately 2 sessions, up to 3 hours for each session, any time within 2 month period | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Field expansion, Collision detection, Walking, Response time