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Objectives: We describe a novel rehabilitation tool for patients with homonymo us hemianopia based on a visual search (VS) paradigm that is portable, inexpensi ve, and easy to deploy. We hypothesised that by training patients to improve the efficiency of eye movements made in their blind field their disability would be alleviated. Methods: Twenty nine patients with homonymous visual field defects (HVFD) without neglect practised VS paradigms in 20 daily sessions over one mont h. Search fields comprising randomly positioned target and distracter elements, differing by a single feature, were displayed for three seconds on a dedicated t elevision monitor in the patientshomes. Improvements were assessed by examinin g response time (RT), error rates in VS, perimetric visual fields (VFs) and visu al search fields (VSFs), before and after treatment. Functional improvements wer e measured using objective visual tasks which represented activities of daily li ving (ADL) and a subjective questionnaire. Results: As a group the patients had significantly shorter mean RT in VS after training (p < 0.001) and demonstrated a variety of mechanisms to account for this. Improvements were confined to the t raining period and maintained at follow up. Three patients had significantly lon ger RT after training. They had high initial error rates which improved with tra ining. Patients performed ADL tasks significantly faster after training and repo rted significant subjective improvements. There was no concomitant enlargement o f the VF, but there was a small but significant enlargement of the VSF. Conclusi on: Patients can improve VS with practice.This usually involves shorter RTs, but occasionally a longer RT in a complex speed accuracy trade off. These changes translate to improved overall visual function, assessed objectively and subject ively, suggesting that they represent robust training effects. The underlying me chanism may involve the adoption of compensatory eye movement strategies.
Objectives: We describe a novel rehabilitation tool for patients with homonymo us hemianopia based on a visual search (VS) paradigm that is portable, inexpensi ve, and easy to deploy. We hypothesised that by training patients to improve the efficiency of eye movements made in Their blind field their disability would be alleviated. Methods: Twenty nine patients with homonymous visual field defects (HVFD) without neglect practiced VS paradigms in 20 daily sessions over one mont h. Search lines comprising randomly positioned target and distracter elements, differing by a single feature, were displayed for three seconds on a dedicated t elevision monitor in the patients’ homes. Improvements were assessed by examinin g response time (RT), error rates in VS, perimetric visual fields (VFs) and visu search fields (VSFs) , before and after treatment. Functional improvements wer e measured using objective visual tasks which represented activities of daily li ving (ADL) and a subjective quest Results: As a group the patients had significantly shorter mean RT in VS after training (p <0.001) and demonstrated a variety of mechanisms to account for this. Improvements were confined to the t raining period and maintained at follow up. Three patients They had high initial error rates which improved with traing. Patients had ADL tasks significantly faster after training and repo rted significant subjective improvements. There was no concomitant enlargement of the VF, but there was a small but significant increasement of the VSF. Conclusi on: Patients can improve VS with practice. This normal pronged shorter shorter RTs, but occasionally a longer RT in a complex speed accuracy trade off. These changes translate to improved overall visual function, rated objectively and subject ively, suggesting that they represent robust training effects. The underlying me chanism may involve the adoption of compensatory eye movement strat egies.