Collision Warning Device for Blind and Visually Impaired

Wearable Collision Warning Device for Blind and Visually Impaired: Clinical Trial (As Part of: 'Development of a Vision Assistive Device for Veterans With Traumatic Brain Injury-Associated Visual Dysfunctions')

This study evaluates a novel collision warning device to help people with severe vision impairment or blindness avoid collisions with obstacles. The main hypothesis to be tested is that the device reduces the number of collisions with obstacles in everyday activities.

Participants with blindness or severe visual field loss (hemianopia or tunnel vision) will be trained to use a collision warning device that alerts them to impending collisions. Participants will use the device at home during everyday mobility for about 1 month. The device is designed to supplement existing mobility devices, such as a long cane or dog guide. The device will provide warnings about potential collisions with mid- or high-level obstacles (which are typically not detected by a long cane).

Inclusion Criteria:

• Blindness (or very limited vision with visual acuity no better than "counting fingers"),
• Or severe peripheral field loss / tunnel vision (≤ 40° remaining visual field) with visual acuity of at least 20/200,
• Or homonymous hemianopia with visual acuity of at least 20/200;
• Able to walk independently either with or without mobility aids such as a long cane or guide dog (but without the aid of a sighted guide);
• Reports at least minor bumps or collisions within the last 3 months;

Exclusion Criteria:

• Currently participating in a mobility training program
• Diagnosed dementia
• Significant cognitive decline
• Participants with hemianopia will be excluded if they have hemianopia for less than 3 months and/or have spatial neglect