Clinical trial NCT04827147: Clinical Trial of Multi-Periscopic Prism Glasses for Hemianopia
Official title: Randomized Controlled Multicenter Clinical Trial of Multi-Periscopic Prism Glasses for Homonymous Hemianopia
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Homonymous Hemianopia
Lead sponsor: Massachusetts Eye and Ear Infirmary
Sponsor class: OTHER
Collaborators: name: National Eye Institute (NEI)
First posted: 2021-04-01
Enrollment: 63
Sex: ALL
Minimum age (years): 7
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

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).

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. 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.

Eligibility criteria: Inclusion Criteria:

* Homonymous hemianopia with or without macular sparing for at least 3 months
* Visual acuity of at least 20/50 in each eye, with correction if needed
* Refractive error in the -12D to +5D range
* Able to walk independently, using a cane or walker if needed
* Able to communicate in English sufficiently to understand the study procedures and how to use the prisms

Exclusion Criteria:

* Central visual field loss in the seeing hemifield of either eye (e.g. from macular degeneration, glaucoma, diabetic retinopathy or other maculopathies)
* Hemi-spatial neglect
* Significant cognitive impairment
* Dementia
* 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

Primary outcomes:
measure: Change in detection rate for hazards approaching from the blind side in the VR walking simulator test
timeFrame: Baseline, After 4 weeks of wearing first pair of prism glasses, After 4 weeks of wearing second pair of prism glasses
Secondary outcomes:
measure: Change in detection response time for hazards approaching from the blind side in the VR walking simulator test
timeFrame: Baseline, After 4 weeks of wearing first pair of prism glasses, After 4 weeks of wearing second pair of prism glasses
measure: Device preference
timeFrame: After 4 weeks of wearing the second pair of prism glasses
measure: Continuation rate (at end of crossover)
timeFrame: After 4 weeks of wearing the second pair of prism glasses
measure: Continuation rate (long term)
timeFrame: At 6 months
Other outcomes:
Locations:
city: Birmingham
country: United States
facility: UAB Center for Low Vision Rehabilitation, Callahan Eye Hospital
state: Alabama
city: Denver
country: United States
facility: UCHealth Sue Anschutz-Rodgers Eye Center
state: Colorado
city: Palm Springs
country: United States
facility: Visual Health and Surgical Center
state: Florida
city: Chicago
country: United States
facility: Illinois College of Optometry
state: Illinois
city: Boston
country: United States
facility: Schepens Eye Research Institute
state: Massachusetts
city: Boston
country: United States
facility: New England College of Optometry
state: Massachusetts
city: Worcester
country: United States
facility: The Eye and Vision Center at MCPHS
state: Massachusetts
city: Worcester
country: United States
facility: UMass Chan Medical School
state: Massachusetts
Study officials:
affiliation: Schepens Eye Research Institute of Massachusetts Eye and Ear
name: Eli Peli, OD MSc
role: PRINCIPAL_INVESTIGATOR
References: