Visual Field Expansion for Hemianopia

Introduction

Modern digital signal processing applications involve applying tools from signal processing to all sorts of data– from streams of images to heart rate time series. More than one million people in the United States suffer from hemianopia, which blinds the vision in one half of the visual field in both eyes as a result of strokes, tumors or trauma. Hemianopia patients are often not aware of what they cannot see and frequently bump into walls, trip over objects or walk into people on the side where the visual field is missing. Recent driving simulation tests affirm that drivers with hemianopia may be more likely to hit pedestrians than those who can see both halves of their visual field.


Visual Field Loss due to Hemianopia

Goals

In this project, we repurposed the head-mounting display system Google Glass, a wearable system that has the capability of projecting augmented information on its display as well as allowing the user to see through it. An application has been developed by our team as a visual aid for patients with hemianopia. The application together with the repurposed Google Glass form a system which provides the patients with an expanded visual field for distance, intermediate, and reading as an augmented view. Using the system, hemianopia patients will be able to make rapid decisions based on their perception of objects and obstacles not normally visible to them without turning their eyes and head. The system generates and displays augmented vision information through an intuitive user interface and based on a user selectable visual field expansion method and the lighting conditions.

Our clinical trials are scheduled to start when 20 patients with complete hemianopia with no cognitive deficit will be enrolled. The patients will be asked to wear the Google Glass and perform 1- a standardized walking obstacle course test; 2- a visual performance test with a driving simulator; and 3- A visual search test. The quality of life of these patients will be evaluated based on their difficulty noticing obstacles on their hemianopia side.


Visual Field Expansion with Google Glass

Potentials

The system will not only impact the hemianopia patients, but also it may offer therapeutic avenues to the patients who have a visual field deficit, such as anterior ischemic optic neuropathy.