Efficacy and predictors of recovery of function after eye movement training in 296 hemianopic patients

Abstract

Compensatory approaches to rehabilitation of vision loss as a result of brain injury are aimed at improving the efficacy of eye movements, enabling patients to bring the otherwise unseen stimuli into their sighted field. Eye movement training has shown promise in a large number of studies in small clinical populations. Nevertheless, there remain two problems; standardisation and wide accessibility. NeuroEyeCoach™ (NEC) has been developed to address both. The therapy is based on the visual search approach and is adaptive to the patient's level of disability and the task difficulty is varied systematically through a combination of set-size and target/distractor similarity. Importantly, the therapy can be accessed online or in clinical settings, to enhance accessibility. Here we have reported on the findings from the first 296 consecutive cases who have accessed and completed NEC online, the largest cohort of patients studied to date. Patients' performance on two objective (visual search times and errors) and one subjective (self-reported disability) measures of performance were assessed before and after therapy. The findings showed that patients improved in search time, had less errors and improved disability scores in 87% (255/294), 80% (236/294) and 66% (167/254) of all cases respectively. We examined factors age, sex, side of blindness, age at the onset of brain injury, and time elapsed between the brain injury and start of therapy as predictors of both objective and subjective measures of improvements. Age was a significant predictor of improved search errors with older patients showing larger improvements. Time between brain injury and intervention negatively influenced search reaction time, however, none of the factors could predict improved subjective reports of disability.

Keywords: Compensatory therapy; Eye-movement; Hemianopia; NeuroEyeCoach™; Rehabilitation; Stroke.