Feasibility Tests for Various Prism Configurations for Visual Field Loss

Mass Eye and Ear

Status

Enrolling

Conditions

Visual Field Defect Homonymous Bilateral

Visual Field Defect, Peripheral

Hemianopia, Homonymous

Tunnel Vision

Visual Field Constriction Bilateral

Treatments

Device: High power prisms

Study type

Interventional

Funder types

Other

NIH

Identifiers

NCT04424979

R01EY023385 (U.S. NIH Grant/Contract)

MPP_Feasibility1

Details and patient eligibility

About

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.

Enrollment

20 estimated patients

Sex

All

Ages

7 to 80 years old

Volunteers

No Healthy Volunteers

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)