Home › Hemianopsia › NCT04424979

Feasibility Tests for Various Prism Configurations for Visual Field Loss

Visual Field Expansion Through Innovative Multi-Periscopic Prism Design

Who can join

Ages 7 to 80 · All sexes

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)

About the study

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.

What is being tested

• High power prisms (device)

Sponsor: Massachusetts Eye and Ear Infirmary · Participants: 20 · Started: Nov 6, 2020

Contact the study team

• Alex Bowers · Phone: 617 912 2512

Official record on ClinicalTrials.gov — NCT04424979

Locations in the U.S.

Conditions

• Hemianopsia

From ClinicalTrials.gov, data retrieved Sep 30, 2026. Each study sets its own eligibility; the study team decides who can join.