Clinical Trial of Multi-Periscopic Prism Glasses for Hemianopia

• ClinicalTrials.gov Identifier: NCT04827147
• Recruitment Status: Not yet recruiting
• First Posted: April 1, 2021
• Last Update Posted: April 1, 2021
• Sponsor: Massachusetts Eye and Ear Infirmary
• Collaborator: National Eye Institute (NEI)
• Information provided by (Responsible Party): Eliezer Peli, Massachusetts Eye and Ear Infirmary

Study Description

Brief Summary:

This clinical trial will evaluate the efficacy of two types of high-power prism glasses that provide field of view expansion for patients with homonymous hemianopia (the complete loss of half the field of vision on the same side in both eyes).

Condition or disease	Intervention/treatment	Phase
Homonymous Hemianopia	Device: Multi-Periscopic Prism (MPP) glasses; Device: Fresnel Peripheral Prism (FPP) glasses	Not Applicable

Detailed Description:

Patients with hemianopic field loss may be unaware of objects in their blind (non-seeing) hemi-field and often experience difficulties with hazards, such as walking into obstacles on the side of the field loss. Prism glasses that provide field of view expansion may be helpful in detecting hazards on the blind side. In this clinical trial, two types of high power prism glasses will be evaluated. A new design of prisms, Multi-Periscopic Prisms (MPP), will be compared to commercially-available permanent Fresnel peripheral prism (FPP) glasses. The extent to which the prismatic devices improve detection of hazards on the side of the field loss and are helpful when walking will be evaluated.

Participants will try each type of prism glasses at home for 4 weeks in counterbalanced order with a washout period between. Prism glasses will be fitted by Low Vision Practitioners at vision rehabilitation clinics. Participants will attend in-office study visits before and after wearing each type of prism glasses. At the in-office visits they will complete a test that involves detecting pedestrian hazards in a video simulating a walk through a busy shopping mall (virtual reality, VR, walking simulator test). In addition, they may be asked to complete questionnaires to record their experiences of using the prism glasses.

After wearing the second pair of prism glasses, participants will be asked to complete a questionnaire comparing the two types of prism glasses and to select their preferred type. A clinical decision will be made as to whether the participant should continue to use either the first or second pair of prism glasses (e.g. if a participant finds one pair of prism glasses helpful for obstacle avoidance when walking). For participants who continue with the prism glasses, telephone follow-up interviews will be conducted after about 6 and 12 months.

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 50 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: Single (Outcomes Assessor)
• Primary Purpose: Treatment
• Official Title: Randomized Controlled Multicenter Clinical Trial of Multi-Periscopic Prism Glasses for Homonymous Hemianopia
• Estimated Study Start Date: October 1, 2021
• Estimated Primary Completion Date: June 1, 2024
• Estimated Study Completion Date: September 1, 2024

Arms and Interventions

Arm	Intervention/treatment
Experimental: MPP first, FPP second; Participants in this arm will receive the MPP in the first period of the crossover and the FPP in the second period.	Device: Multi-Periscopic Prism (MPP) glasses; Spectacles with multi-periscopic prisms mounted as oblique peripheral prism segments; Device: Fresnel Peripheral Prism (FPP) glasses; Spectacles with conventional permanent Fresnel prisms mounted as oblique peripheral prism segments
Experimental: FPP first, MPP second; Participants in this arm will receive the FPP in the first period of the crossover and the MPP in the second period.	Device: Multi-Periscopic Prism (MPP) glasses; Spectacles with multi-periscopic prisms mounted as oblique peripheral prism segments; Device: Fresnel Peripheral Prism (FPP) glasses; Spectacles with conventional permanent Fresnel prisms mounted as oblique peripheral prism segments

Outcome Measures

Primary Outcome Measures :

1. Change in detection rate for hazards approaching from the blind side in the VR walking simulator test [ Time Frame: Baseline, After 4 weeks of wearing first pair of prism glasses, After 4 weeks of wearing second pair of prism glasses ]
   Number of pedestrians detected as a percentage of the total number of pedestrian events.

Secondary Outcome Measures :

1. Change in detection response time for hazards approaching from the blind side in the VR walking simulator test [ Time Frame: Baseline, After 4 weeks of wearing first pair of prism glasses, After 4 weeks of wearing second pair of prism glasses ]
   Response time from pedestrian target onset to the first button press to indicate detection
2. Device preference [ Time Frame: After 4 weeks of wearing the second pair of prism glasses ]
   Number of participants selecting each device as a percentage of the total number of participants enrolled
3. Continuation rate (at end of crossover) [ Time Frame: After 4 weeks of wearing the second pair of prism glasses ]
   Number of participants with a clinical decision to continue with prism glasses at the end of the crossover as a percentage of the total number of participants enrolled.
4. Continuation rate (long term) [ Time Frame: At 6 months ]
   Number of participants still wearing prism glasses as a percentage of total number of participants enrolled.

Eligibility Criteria

• Ages Eligible for Study: 7 Years to 80 Years (Child, Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Criteria

Inclusion Criteria:

• Homonymous hemianopia with or without macular sparing for at least 6 months
• Visual acuity of at least 20/50 in each eye, with correction if needed
• Able to walk independently, using a cane or walker if needed

Exclusion Criteria:

• Central visual field loss in the seeing hemifield (e.g. from macular degeneration, glaucoma, diabetic retinopathy or other maculopathies)
• Hemi-spatial neglect
• Significant cognitive impairment
• Dementia
• History of seizures in last 6 months
• Any other physical or mental disabilities, or general health problems that could impair the ability to be independently mobile (i.e., walk ), participate in the VR walking simulator test or use the prism glasses

Contacts and Locations

Contacts

Contact: Alex Bowers, PhD; 617-912-2512; alex_bowers@meei.harvard.edu

Locations

United States, Massachusetts

Schepens Eye Research Institute

Boston, Massachusetts, United States, 02114

Sponsors and Collaborators

Massachusetts Eye and Ear Infirmary

National Eye Institute (NEI)

Investigators

• Principal Investigator: Eli Peli, OD MSc; Schepens Eye Research Institute of Massachusetts Eye and Ear

More Information

• Responsible Party: Eliezer Peli, Senior Scientist, Massachusetts Eye and Ear Infirmary
• ClinicalTrials.gov Identifier: NCT04827147
• Other Study ID Numbers: MPPvsFPP; R01EY023385 ( U.S. NIH Grant/Contract )
• First Posted: April 1, 2021
• Last Update Posted: April 1, 2021
• Last Verified: March 2021

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: Yes
• Product Manufactured in and Exported from the U.S.: No

Additional relevant MeSH terms:

Hemianopsia; Vision Disorders; Sensation Disorders; Neurologic Manifestations; Nervous System Diseases; Blindness; Eye Diseases; Methamphetamine; Central Nervous System Stimulants; Physiological Effects of Drugs; Sympathomimetics; Autonomic Agents; Peripheral Nervous System Agents; Dopamine Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Adrenergic Agents; Adrenergic Uptake Inhibitors; Neurotransmitter Uptake Inhibitors; Membrane Transport Modulators; Dopamine Uptake Inhibitors