SmartEye: Developing a Novel Eye Tracking System for Quantitative Assessment of Oculomotor Abnormalities

Eye movements are a continuous and ubiquitous part of sensory perception. To properly generate highly accurate and co-ordinate ocular movements, a vast network of brain areas are engaged, from low-level visual processing to motor control of gaze orientation. This renders oculomotor system vulnerable to various neurological disorders with unique clinical patterns. Therefore, oculomotor examination can serve as an early and sensitive indicator for various neurological conditions. A simple-to-use, clinically valid system for objectively assessing the oculomotor function can thus bring a paradigm shift in diagnosis and treatment of brain disorders. In principal accordance, this paper presents a gaze assessment tool, called SmartEye, which is based on eye fixation, smooth pursuit, and blinking in response to both static and dynamic visual stimuli. The gaze related indices were evaluated in real-time by SmartEye and these were mapped to the reported pathological state in chronic (> 3 months) patients with stroke. Our preliminary feasibility study with eight pairs of chronic (> 3 months) stroke survivors and healthy individuals revealed that gaze related indices in response to both static and dynamic visual stimuli may serve as potential quantitative biomarkers for stroke assessment.