Oculographic analysis of saccadic eye movements in patients with vascular encephalopathy

Abstract

Objective – to assess the diagnostic value of objective saccadic eye-movement parameters for early detection of neurocognitive deficit in patients with chronic cerebral ischemia (vascular encephalopathy, stages I–II). Materials and methods. Fifty participants were examined: 22 patients with vascular encephalopathy (MMSE 26.3±2.4) and 28 conditionally healthy volunteers (MMSE 28.8±1.1). Eye movements were recorded using the Pupil Invisible video-oculography system. The protocol included the Gap, Overlap, and Prediction tasks. Latency, gain, coefficient of variation (CV), and error rate were analyzed. Results. In the Gap task, mean latency and gain did not differ, whereas CV was more than twofold higher in patients (35.9±13.2 % vs 16.1±4.5 %; p=0.012). In the Overlap task, a trend toward longer latency was observed (p=0.07) with no difference in the gap effect (p=0.41). The most pronounced differences were found in the Prediction task: increased latency (p=0.041) and a higher error rate (p=0.038). Conclusion. In vascular encephalopathy stages I–II, measures of response stability and performance quality in cognitively demanding tasks are the most informative.