Prism Glasses for Hemianopia
What You Need to Know Before You Apply
What is the purpose of this trial?
This trial tests two types of special glasses to assist individuals who have lost half of their vision on the same side in both eyes, a condition known as homonymous hemianopia. The glasses, Fresnel Peripheral Prism (FPP) and Multi-Periscopic Prism (MPP), aim to expand the field of view. Participants will try both types to determine which better improves vision. This study suits those who have experienced this vision issue for at least three months, can see reasonably well with each eye, and can walk independently. As an unphased trial, it offers a unique opportunity to explore innovative solutions for vision improvement.
Will I have to stop taking my current medications?
The trial information does not specify whether you need to stop taking your current medications.
What prior data suggests that these prism glasses are safe for patients with homonymous hemianopia?
Studies have shown that both types of prism glasses, Fresnel Peripheral Prism (FPP) and Multi-Periscopic Prism (MPP), are generally well-tolerated by individuals with homonymous hemianopia, a condition where half of the field of vision is lost on the same side in both eyes. Research indicates that many find FPP glasses helpful, often reporting improved ability to avoid obstacles. This suggests the glasses are safe for everyday use.
For MPP glasses, early findings suggest that any side effects are manageable and do not significantly impact daily activities. The MPP glasses provide a wider field of view, aiding in spotting hazards, especially when walking. No significant negative effects have been reported for either type of glasses, making them a promising option for improving vision in those with hemianopia.12345Why are researchers excited about this trial's treatments?
Researchers are excited about the use of prism glasses for hemianopia because these glasses offer a novel way to improve vision by redirecting light into the blind areas. Unlike traditional rehabilitation strategies that focus on compensatory techniques, the Fresnel Peripheral Prism (FPP) glasses and Multi-Periscopic Prism (MPP) glasses aim to directly expand the visual field. The FPP glasses use high-powered prisms to shift images from the blind side into the seeing side, while the MPP glasses employ an innovative multi-periscopic design to maximize peripheral vision. These approaches could provide a more immediate and practical solution for those with hemianopia, enhancing their ability to navigate daily environments safely and independently.
What evidence suggests that these prism glasses are effective for hemianopia?
Research shows that both Fresnel Peripheral Prism (FPP) glasses and Multi-Periscopic Prism (MPP) glasses can assist individuals with homonymous hemianopia, a condition where half of the vision is lost on the same side in both eyes. In this trial, participants will use either FPP or MPP glasses during different periods of a crossover design. Studies indicate that FPP glasses improve mobility and help users avoid obstacles, facilitating safer movement. Similarly, MPP glasses widen the field of view by 42 degrees, aiding in hazard detection and enhancing safety. Both types of glasses have effectively expanded visual fields, making them valuable tools for those with this vision condition.12678
Who Is on the Research Team?
Eli Peli, OD MSc
Principal Investigator
Schepens Eye Research Institute of Massachusetts Eye and Ear
Are You a Good Fit for This Trial?
This trial is for individuals with homonymous hemianopia, which means they've lost half of their field of vision in both eyes. Participants must have at least 20/50 vision with correction, a refractive error within -12D to +5D, and be able to walk independently. They should not have conditions like dementia or significant cognitive impairment that would affect mobility or the use of prism glasses.Inclusion Criteria
Exclusion Criteria
Timeline for a Trial Participant
Screening
Participants are screened for eligibility to participate in the trial
Treatment
Participants will try each type of prism glasses at home for 4 weeks in counterbalanced order
Follow-up
Participants are monitored for safety and effectiveness after treatment, including telephone follow-up interviews
What Are the Treatments Tested in This Trial?
Interventions
- Fresnel Peripheral Prism (FPP) glasses
- Multi-Periscopic Prism (MPP) glasses
Find a Clinic Near You
Who Is Running the Clinical Trial?
Massachusetts Eye and Ear Infirmary
Lead Sponsor
National Eye Institute (NEI)
Collaborator