Header

UZH-Logo

Maintenance Infos

Gaze fixation deficits and their implication in ataxia-telangiectasia - Zurich Open Repository and Archive


Shaikh, A G; Marti, S; Tarnutzer, A A; Palla, A; Crawford, T O; Straumann, D; Taylor, A M; Zee, D S (2009). Gaze fixation deficits and their implication in ataxia-telangiectasia. Journal of Neurology, Neurosurgery, and Psychiatry, 80(8):858-864.

Abstract

Ataxia-telangiectasia (A-T) is an autosomal recessive disorder characterized by progressive neurological deficits, including prominent ocular motor dysfunction. Unstable fixation often leads to difficulty reading and blurred vision. Here we characterize the disturbance of visual fixation in A-T. METHODS: We recorded eye movements from 13 A-T patients (with dual search coils in five patients and with video oculography in 7) during attempted fixation. RESULTS: Two abnormalities - nystagmus and saccadic intrusions - were common. Horizontal, vertical, and torsional nystagmus was present in straight-ahead (spontaneous nystagmus) and eccentric gaze (gaze-evoked nystagmus). In eight patients the horizontal nystagmus changed directions - periodic alternating nystagmus (PAN). Two types of saccadic intrusions occurred - micro-saccadic oscillations (SO) and square-wave saccadic intrusions (SWSI). SO were small-amplitude (0.1-0.9 degrees ) and high-frequency (14-33Hz) back-to-back horizontal saccades. The SWSI ranged between 1-18 degrees (median: 3 degrees ) with an intersaccadic interval ranging between 50-800 milliseconds (median: 300 milliseconds). The potential impact of abnormal gaze stabilization on vision was quantified. DISCUSSION: Degeneration of cerebellar Purkinje neurons disinhibit the fastigial (FOR) and vestibular nuclei (VN). Disinhibition of VN can cause nystagmus including PAN, while disinhibition of FOR can affect saccade generating mechanisms leading to SWSI and SO.

Abstract

Ataxia-telangiectasia (A-T) is an autosomal recessive disorder characterized by progressive neurological deficits, including prominent ocular motor dysfunction. Unstable fixation often leads to difficulty reading and blurred vision. Here we characterize the disturbance of visual fixation in A-T. METHODS: We recorded eye movements from 13 A-T patients (with dual search coils in five patients and with video oculography in 7) during attempted fixation. RESULTS: Two abnormalities - nystagmus and saccadic intrusions - were common. Horizontal, vertical, and torsional nystagmus was present in straight-ahead (spontaneous nystagmus) and eccentric gaze (gaze-evoked nystagmus). In eight patients the horizontal nystagmus changed directions - periodic alternating nystagmus (PAN). Two types of saccadic intrusions occurred - micro-saccadic oscillations (SO) and square-wave saccadic intrusions (SWSI). SO were small-amplitude (0.1-0.9 degrees ) and high-frequency (14-33Hz) back-to-back horizontal saccades. The SWSI ranged between 1-18 degrees (median: 3 degrees ) with an intersaccadic interval ranging between 50-800 milliseconds (median: 300 milliseconds). The potential impact of abnormal gaze stabilization on vision was quantified. DISCUSSION: Degeneration of cerebellar Purkinje neurons disinhibit the fastigial (FOR) and vestibular nuclei (VN). Disinhibition of VN can cause nystagmus including PAN, while disinhibition of FOR can affect saccade generating mechanisms leading to SWSI and SO.

Citations

17 citations in Web of Science®
19 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

90 downloads since deposited on 22 Jun 2009
17 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:04 Faculty of Medicine > Neuroscience Center Zurich
04 Faculty of Medicine > Center for Integrative Human Physiology
04 Faculty of Medicine > University Hospital Zurich > Clinic for Neurology
Dewey Decimal Classification:570 Life sciences; biology
610 Medicine & health
Language:English
Date:8 April 2009
Deposited On:22 Jun 2009 14:52
Last Modified:28 May 2017 20:30
Publisher:BMJ Publishing Group
ISSN:0022-3050
Publisher DOI:https://doi.org/10.1136/jnnp.2008.170522
PubMed ID:19357126

Download

Preview Icon on Download
Preview
Content: Accepted Version
Filetype: PDF
Size: 2MB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations