slide1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Introduction PowerPoint Presentation
Download Presentation
Introduction

Loading in 2 Seconds...

play fullscreen
1 / 10

Introduction - PowerPoint PPT Presentation


  • 117 Views
  • Uploaded on

Mild TBI causes a long-lasting elevation of the transcranial magnetic stimulation (TMS) motor threshold.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Introduction' - fulton-fernandez


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

Mild TBI causes a long-lasting elevation of the transcranial magnetic stimulation (TMS) motor threshold

JussiTallus1, Pantelis Lioumis2, Heikki Hämäläinen3, Seppo Kähkönen2, Olli Tenovuo*11Department of Neurology, University of Turku, Finland, 2Biomag Laboratory, Finland, 3Department of Psychology, University of Turku, Finland

* presenting author

introduction
Introduction
  • Mild traumatic brain injury (mTBI) is often associated with long lasting symptoms that may be caused partly by diffuse damage to cerebral white matter tracts
  • There is a major clinical need to develop reliable methodology to assess whether prolonged symptoms after mTBI have an organic basis
introduction1
Introduction
  • Cortical excitability can be evaluated by recording electromyographic (EMG) responses elicited by single pulse TMS and measuring the minimum intensity (motor threshold; MT) that can evoke motor evoked potentials (MEPs).
  • MT provides a relatively easy measure of corticospinal tract integrity.
objectives
Objectives

To evaluate whether corticospinal tract integrity measured with TMS elicited MT measurement is altered in subjects with chronic symptoms after mTBI

material and methods
Material and methods
  • Nineteen mTBI patients, 11 with persistent symptoms and 8 recovered
  • The subjects had suffered a mTBI (GCS 13 – 15) on the average five years earlier
  • All subjects had normal MRIs in visual inspection
  • Nobody used CNS affecting medications
  • Nine healthy controls
material and methods1
Material and methods
  • Navigated TMS, stimulation on the left primary motor cortex
  • MEPs recorded from the right m. abductor pollicis brevis by EMG
  • MT is defined as the lowest stimulation intensity at which 5 out of 10 pulses evoke 50 µV MEP or greater
results
Results
  • The average MT was 43.0 % (SD ± 0.8) of maximum stimulator output in the control group.
  • Both patient groups had statistically significantly higher MTs, 52.5 % (SD ± 3.1) in the symptomatic and 54.6 % (SD ± 3.4) in the recovered group.
results1
Results

p = 0.012

p = 0.011

conclusions
Conclusions
  • MT may be a useful measure in evaluating brain damage caused by mTBI.
  • This study shows that MT elevation can last until at least several years after the injury, and that it is not necessarily related to subjective complaints.
conclusions1
Conclusions
  • The similar results of the symptomatic and recovered groups imply that simple MT by itself is not sufficient as a measure of injury severity or outcome, but it can be useful in combination with other methods.
  • It is noteworthy that also fully recovered mTBI subjects show an abnormal MT, which suggests a persistent injury also in these subjects