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Introduction/Background Proprioceptive impairment, as in the case of ataxic neuropathy, leads to visual compensation. The techniques of gaze analysis in static condition have been widely explored, but only recent technological innovations have allowed them to be associated with dynamic movements. In this context, we chose to use the eye-tracker glasses to analyze gaze and possible visual strategies established by these patients during gait. Material and method Three groups were selected: 15 health young subjects, 15 elderly subjects and 15 subjects with ataxic neuropathy. The experimental protocol consists of walk in a corridor with three different segments wearing the eye-tracker glasses. As for the gaze direction analysis we pre-defined classifications of the image called “observables”: these classifications consists on the time spent looking at the floor, the middle and the side parts of the corridor. Results We observed a significant difference between the two groups of health subjects and the patients regarding the time spent looking at the “observables”. Fisher's post-hoc results were: floor (F 2.132 = 37; P ≤ .0001); middle (F 2.132 = 9,8; P ≤ .0001) and the side parts (F 2.132 = 11,5; P ≤ .0001). We observed a better reproducibility of the evaluation in the three different segments by analyzing the time spent looking at the floor (F 4.84 = 1.4; P = .244), where no significant statistical difference on the performance of the subjects were found. Conclusion The eye-tracker glasses have proven to be a relevant tool for the analysis of visual compensation, both reproducible and sensitive to the pathology. This technology has helped us to quantitatively characterize the visual strategy implemented by ataxic patients during gait.

Introduction Les sujets presentant une neuropathie ataxiante ont une atteinte sensitive predominante des membres inferieurs qu’ils tendent a compenser en augmentant l’utilisation des entrees visuelles. Cette etude vise a etudier la compensation visuelle de ces patients en conditions dynamiques de marche en utilisant l’eye-tracker. Materiel et methode Ce dispositif integre une camera fixee directement sur des lunettes qui permet d’analyser la direction du regard pendant la marche. Trois groupes ont ete selectionnes : 10 sujets temoins jeunes, 10 sujets temoins plus âgees et 10 sujets presentant une neuropathie ataxiante. Le protocole experimental consiste a marcher dans 3 couloirs differents en portant l’eye-tracker. Pour cette premiere approche, en ce qui concerne la direction du regard nous avons etudie le temps passe par chaque patient en regardant le sol. Resultats La reproductibilite des trajets realises par les sujets a ete calculee par Anova a mesure repetee confirmant la reproductibilite de l’evaluation dans les differents secteurs de marche. Nous avons observe une difference significative entre les deux groups des sujets temoins et les patients ( p Discussion – conclusion La technologie eye-tracking offre la possibilite d’une evaluation quantitative du processus visuel et attentionnel des sujets. Cela nous a permis de montrer une difference de compensation visuelle lors de la marche entre les groupes des temoins et les patients. L’eye-tracker s’avere un outil pertinent pour l’analyse de la compensation visuelle lors de la marche, a la fois reproductible et sensible a la pathologie testee dans cette etude.