Feasibility Tests for Various Prism Configurations for Visual Field Loss
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: High power prisms.
- Who it may be relevant to
- Registry conditions: Hemianopia, Homonymous, Tunnel Vision, Visual Field Defect, Peripheral, Visual Field Constriction Bilateral. Basic parameters: 7 years — 80 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
Visual Field Expansion Through Innovative Multi-Periscopic Prism Design
Overview
The investigators will develop and test different configurations of high-power prisms to expand the field of vision of patients with visual field loss to assist them with obstacle detection when walking. The study will involve multiple visits (typically four) to Schepens Eye Research Institute for fitting and testing with the prism glasses. The overall objective is to determine best designs and fitting parameters for implementation in prism devices for future clinical trials.
Interventions
- Device High power prisms
High power prisms designed to shift images from blind areas into portions of the wearer's remaining, seeing, field of vision
Primary outcome measures
- Field of view expansion [Time frame: Through study completion, an average of four months]
Secondary outcome measures (1)
- Pedestrian detection rate [Time frame: Through study completion, an average of four months]
Eligibility criteria
Inclusion criteria
- Visual field loss, either peripheral field loss or hemianopic field loss
- Visual acuity of at least 20/50 in the better eye
- In sufficiently good health to be able to complete sessions lasting 2-4 hours
- Able to independently walk short distances
- Able to give voluntary, informed consent
- Able to speak English
Exclusion criteria
- Any physical or mental impairments, including cognitive dysfunction, balance problems or other deficits that could impair the ability to walk or use the prism spectacles
- A history of seizures in the last 6 months
- Hemispatial neglect (subjects with hemianopic field loss only)
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- N/A
- Model
- Single group
- Masking
- Open label
- Primary purpose
- Device feasibility
Study locations
United States · 1 center
- Schepens Eye Research Institute — Boston
Publications
- Bowers AR, Manda S, Shekar S, Hwang AD, Jung JH, Peli E. Pilot study of a pedestrian collision detection test for a multisite trial of field expansion devices for hemianopia. Optom Vis Sci. 2024 Jun 1;101(6):408-416. doi: 10.1097/OPX.0000000000002152. PMID 38990239
Identifiers
NCT: NCT04424979 · MPP_Feasibility1 · R01EY023385