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Homonymous HemianopiaNCT04827147

Clinical Trial of Multi-Periscopic Prism Glasses for Hemianopia

A study testing Multi-Periscopic Prism (MPP) glasses and Fresnel Peripheral Prism (FPP) glasses in people with Homonymous Hemianopia, run by Massachusetts Eye and Ear Infirmary at 8 sites in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial 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). Read more about this study

Who is it for?
Ages 7 years and older
Conditions the study is for
Homonymous Hemianopia
What is being tested?
Multi-Periscopic Prism (MPP) glasses and Fresnel Peripheral Prism (FPP) glasses
Type of treatment
Medical device
Could I receive a placebo?
No, everyone receives an active treatment
How many people
64 participants
Where
8 sitesUnited States
Study dates
3 Apr 2023to 30 Apr 2026
Phase
Interventional
Are there results?
Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 7 years and older
  • All sexes
  • No healthy volunteers
  • Child, Adult, Older adult

Who may be able to join

  • 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

Who cannot join

  • 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

Trial locations and contacts

8 sites in 1 country.

8 sites in 1 country

United States8 sites
  • UAB Center for Low Vision Rehabilitation, Callahan Eye Hospital

    Birmingham, Alabama, 35233

  • Schepens Eye Research Institute

    Boston, Massachusetts, 02114

  • New England College of Optometry

    Boston, Massachusetts, 02215

  • Illinois College of Optometry

    Chicago, Illinois, 60616

  • UCHealth Sue Anschutz-Rodgers Eye Center

    Denver, Colorado, 80045

  • Visual Health and Surgical Center

    Palm Springs, Florida, 33461

  • The Eye and Vision Center at MCPHS

    Worcester, Massachusetts, 01608

  • UMass Chan Medical School

    Worcester, Massachusetts, 01655

Other trials in United States

About this study

Official title: Randomized Controlled Multicenter Clinical Trial of Multi-Periscopic Prism Glasses for Homonymous Hemianopia

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).

Read the 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.

Being tested
Multi-Periscopic Prism (MPP) glasses, Fresnel Peripheral Prism (FPP) glasses
Medical subject headings
Hemianopsia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Multi-Periscopic Prism (MPP) glassesDevice

    Spectacles with multi-periscopic prisms mounted as oblique peripheral prism segments

  • Fresnel Peripheral Prism (FPP) glassesDevice

    Spectacles with conventional permanent Fresnel prisms mounted as oblique peripheral prism segments

Study groups in NCT04827147
Study groupRoleWhat they receive
MPP first, FPP secondExperimentalParticipants in this arm will receive the MPP in the first period of the crossover and the FPP in the second period.
Receives: Device: Multi-Periscopic Prism (MPP) glasses; Device: Fresnel Peripheral Prism (FPP) glasses
FPP first, MPP secondExperimentalParticipants in this arm will receive the FPP in the first period of the crossover and the MPP in the second period.
Receives: Device: Multi-Periscopic Prism (MPP) glasses; Device: Fresnel Peripheral Prism (FPP) glasses

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Improvement in Blind-side Detection Rate for Hazards Approaching at a Bearing Angle of 40 Degrees

    Improvement in detection rate with prism glasses for hazards approaching from the blind side at a bearing angle of 40 degrees in the VR walking simulator test. Improvement is a binary outcome, defined as blind-side detection rate (number of pedestrians detected as a percentage of the total number of pedestrian events) which is significantly higher (z-test for two proportions) with than without prism glasses at the same visit.

    Measured: Immediately after each 4-week intervention

Secondary outcomes (2)
  1. Improvement in Blind-side Detection Rate for Hazards Approaching at a Bearing Angle of 20 Degrees

    Improvement in detection rate with prism glasses for hazards approaching from the blind side at a bearing angle of 20 degrees in the VR walking simulator test. Improvement is a binary outcome, defined as blind-side detection rate (number of pedestrians detected as a percentage of the total number of pedestrian events) which is significantly higher (z-test for two proportions) with than without prism glasses at the same visit.

    Measured: Immediately after each 4-week intervention

  2. Device Preference

    Number of participants selecting each device as a percentage of the total number of participants enrolled

    Measured: Immediately after the second 4-week intervention

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted1 Apr 2021
  2. Study start3 Apr 2023
  3. Primary completion30 Apr 2025
  4. Study completion30 Apr 2026

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Crossover
Masking
Single blind
Who is masked
Outcomes assessor
Enrolment
64 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04827147
Sponsor's protocol ID
2021P003649
Other IDs
R01EY023385
Status last verified
Jul 2026
First submitted
25 Mar 2021
Last updated
19 Aug 2026
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
Yes

Publications

  • Bowers AR, Manda S, Shekar S, Hwang AD, Jung JH, Peli E. A randomized crossover clinical trial of multi-periscopic and Fresnel peripheral prism glasses for hemianopia. Optom Vis Sci. 2026 Jun;103(6):e70072. doi: 10.1002/ovs2.70072.

    PubMed 42274646

Questions about this trial

What is this clinical trial studying?

A study testing Multi-Periscopic Prism (MPP) glasses and Fresnel Peripheral Prism (FPP) glasses in people with Homonymous Hemianopia, run by Massachusetts Eye and Ear Infirmary at 8 sites in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 19 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 8 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

Yes. Results are posted in the registry (first posted 13 Mar 2026). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Improvement in Blind-side Detection Rate for Hazards Approaching at a Bearing Angle of 40 Degrees (time frame: Immediately after each 4-week intervention). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04827147, which also lists 1 linked publication.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 Aug 2026.

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