Influence of Gaze Shift and Emotions on Symptoms of Blepharospasm
Blepharospasm (BEB) is a focal dystonia characterized by forceful, involuntary contractions of the orbicularis oculi muscle. (Jankovic et al 1983) Patients with BEB report task and situation specific modulations of their symptoms. So called "sensory tricks" are actions that minimize symptoms and include concentrating, talking, pulling on the eyelids, blowing air, and applying pressure to the periocular or temple region. (Weiner 1984) Many patients describe that other tasks/situations are exacerbate their symptoms specifically under bright fluorescent lights and stress. (Burke 1984) Earlier studies showed that blink patterns differ between BEB patients and control during rest, reading and talking.
In healthy subjects gaze evoked blinks are a physiologic phenomenon: initiation of gaze shifts evoke a blink, blinks facilitate gaze shifts. (Evinger 1994) In healthy subjects emotions and thoughts influence gaze shifts and blink rate. (Leal 2008, de Genaro 1988) However, little is known about various task and emotion specific influences on symptoms of BEB (e.g. expecting a gaze shift might worsen symptoms while driving a car).
Differences in emotion and gaze related blink patterns between patients and controls will contribute to the understanding of the pathophysiology of BEB. This might offer new therapeutic options, e.g. symptom modulation.
The investigators hypothesize that blink patterns, measured by duration and frequency of pupillary occlusion differ between patients and control, when performing gaze shifts and emotion related blink patterns, measured by duration and frequency of pupillary occlusion differ between patients and controls.
The aim of this pilot trial is to assess differences in gaze evoked and emotion related blink patterns between patients and controls. These differences might contribute to the understanding of the pathophysiology of BEB.
|Study Design:||Observational Model: Case Control
Time Perspective: Prospective
|Official Title:||The Influence of Gaze Shift and Emotions on Symptoms of Blepharospasm- a Pilot Study.|
- Duration and frequency of pupillary occlusion [ Time Frame: At baseline ] [ Designated as safety issue: No ]Duration and frequency of pupillary occlusion during different tasks and situations will be studied via videooculography
- Number of blinks and spasms. [ Time Frame: At baseline ] [ Designated as safety issue: No ]Number of blinks and spasms, registered by videotape of the eyes during different tasks and situations.
|Study Start Date:||December 2014|
|Estimated Study Completion Date:||December 2015|
|Estimated Primary Completion Date:||December 2015 (Final data collection date for primary outcome measure)|
Blepharospasm, patient's group
Healthy control subjects
Please refer to this study by its ClinicalTrials.gov identifier: NCT01759745
|Contact: Gottfried Kranz, Doz.Dr.||+43 1 40400 ext firstname.lastname@example.org|
|Contact: Kirsten Elwischger, Dr.||+43 699 email@example.com|
|Department of Neurology, Medical University of Vienna||Not yet recruiting|
|Vienna, Austria, 1090|
|Contact: Gottfried Kranz, Doz.Dr. +43 1 40400 ext 3120 firstname.lastname@example.org|
|Contact: Kirsten Elwischger, Dr. +43 699 11605963 email@example.com|
|Sub-Investigator: Kirsten Elwischger, Dr.|
|Sub-Investigator: Gottfried Kranz, Doz.Dr.|
|Principal Investigator:||Thomas Sycha, Prof.Dr.||Medical University of Vienna|