Neurology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Correspondence:
Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when Correspondence are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Barton, J. J.
Right arrow Articles by Sharpe, J. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Barton, J. J.
Right arrow Articles by Sharpe, J. A.

Neurology, Vol 45, Issue 11 2065-2072, Copyright © 1995 by American Academy of Neurology

ARTICLES

Saccadic duration and intrasaccadic fatigue in myasthenic and nonmyasthenic ocular palsies

JJ Barton, A Jama and JA Sharpe
Neuro-ophthalmology Unit, Toronto Hospital Neurological Center, ON, Canada.

We measured the duration and amplitude of saccades in three normal subjects, eight patients with myasthenia gravis, and eight patients with nonmyasthenic ocular palsies. Saccades were examined at the start of a repetitive saccade task, after 3 minutes of activity, and 1 minute after administration of edrophonium. The duration of saccades was prolonged initially in both myasthenic and nonmyasthenic palsies. Activity did not produce significant differences among the three groups in either the slope of the duration-amplitude relationship or the predicted durations of saccades of 5 degrees, 10 degrees, or 15 degrees. However, durations decreased in myasthenia but increased in nonmyasthenic palsies after edrophonium. Much of this decrease in myasthenic saccadic duration was due to reduction in deceleration time, indicating resolution of intrasaccadic fatigue after edrophonium administration. However, the relation of deceleration fraction (deceleration time divided by total duration) to total duration remained constant in all subject groups. Analysis of saccadic duration is a useful means of interpreting responses to edrophonium because it incorporates data from saccades of a wide range of amplitudes into a linear relation between duration and amplitude.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1995 by AAN Enterprises, Inc.