Citation

Miller AB, Lajoie K, Strath RA, Neima DR, Marigold DS. J. Glaucoma. 2018; 27(1): 55-63.

Affiliation

*Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada †Ophthalmology Private Practice, New Westminster, British Columbia, Canada.

Copyright

(Copyright © 2018, Lippincott Williams and Wilkins)

DOI

10.1097/IJG.0000000000000819

PMID

29117005

Abstract

PURPOSE: Vision normally provides environmental information necessary to direct the foot to safe locations during walking. Peripheral visual field loss limits what a person can see, and may alter how a person visually samples the environment. Here we tested the hypothesis that the spatial-temporal coupling between gaze and stepping in a precision-based walking task is altered in persons with glaucoma, particularly under dual task situations, and results in reduced foot-placement accuracy.

METHODS: Twenty persons with glaucoma and twenty normally-sighted controls performed a precision walking task that involved stepping to the center of four targets under three conditions: targets only, walking and counting backwards to simulate a conversation, and walking while performing a concurrent visual search task to simulate locating a landmark. We quantified foot-placement error and error variability with respect to the targets, as well as saccade and fixation timing with respect to foot placement.

RESULTS: Compared to controls, persons with glaucoma looked earlier at future stepping targets (with respect to toe-off of the foot) in the targets only and count conditions, and transferred gaze away sooner from the current stepping target in all conditions (P<0.05). Persons with glaucoma also had increased foot-placement error, particularly in the count condition, and increased foot-placement error variability compared to normally-sighted controls (P<0.05).

CONCLUSIONS: Glaucoma significantly disrupts gaze-foot coordination and results in less accurate foot placement when precision is required during walking. This may increase the risk of trips and falls in this population.

Language: en