Skip Navigation


Brain Advance Access originally published online on January 30, 2008
Brain 2008 131(4):1035-1045; doi:10.1093/brain/awm323
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
131/4/1035    most recent
awm323v1
Right arrow Alert me when this article is cited
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 ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Right arrow Disclaimer
Google Scholar
Right arrow Articles by Fahey, M. C.
Right arrow Articles by Delatycki, M. B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Fahey, M. C.
Right arrow Articles by Delatycki, M. B.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author (2008). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Vestibular, saccadic and fixation abnormalities in genetically confirmed Friedreich ataxia

Michael C. Fahey1,2, Phillip D. Cremer3, Swee T. Aw4, Lynette Millist5, Michael J. Todd3, Owen B. White5, Michael Halmagyi4, Louise A. Corben1, Veronica Collins1, Andrew J. Churchyard6, Kim Tan3, Lionel Kowal7 and Martin B. Delatycki1,2

1Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, 2Department of Paediatrics, University of Melbourne, Victoria, 3Department of Neurology, Royal North Shore Hospital, 4Department of Neurology, Royal Prince Alfred Hospital, New South Wales, 5Department of Neurology, Royal Melbourne Hospital, 6Monash Neurology, Monash Medical Centre and 7Department of Ophthalmology, Royal Victorian Eye and Ear Hospital, Victoria, Australia

Correspondence to: Associate Professor Martin Delatycki, Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Flemington Road, Parkville, Victoria 3052, Australia E-mail: martin.delatycki{at}ghsv.org.au

Friedreich ataxia (FRDA), the commonest of the inherited ataxias, is a multisystem neurodegenerative condition that affects ocular motor function. We assessed eye movement abnormalities in 20 individuals with genetically confirmed FRDA and compared these results to clinical measures. All subjects were assessed with infrared oculography. Fifteen individuals underwent a full protocol of eye movement recordings. Ten subjects were analysed using two-dimensional scleral coil equipment and five using three-dimensional scleral coil recording equipment. We also recorded visual quality of life, Sloan low contrast letter acuity and Friedreich Ataxia Rating Scale scores to compare to the visual measures. Whilst saccadic velocity was essentially normal, saccadic latency was prolonged. The latency correlated with clinical measures of disease severity, including the scores for the Friedreich Ataxia Rating Scale and the Sloan low contrast letter acuity tests. Fixation abnormalities consisting of square wave jerks and ocular flutter were common, and included rare examples of vertical square wave jerks. Vestibular abnormalities were also evident in the group, with markedly reduced vestibulo-ocular reflex gain and prolonged latency. The range of eye movement abnormalities suggest that neurological dysfunction in FRDA includes brainstem, cortical and vestibular pathways. Severe vestibulopathy with essentially normal saccadic velocity are hallmarks of FRDA and differentiate it from a number of the dominant spinocerebellar ataxias. The correlation of saccadic latency with FARS score raises the possibility of its use as a biomarker for FRDA clinical trials.

Key Words: Friedreich ataxia; ocular-motor; vision; saccades; biomarker

Abbreviations: FRDA, Friedreich ataxia; SLCLC, Sloan Low Contrast Letter Chart; SWJ, square wave jerks

Received August 18, 2007. Revised December 2, 2007. Accepted December 3, 2007.


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.