Neurophysiology Plus Iceland is represented at TMS-workshop in Denmark

by Ovidiu C. Banea

Questions for TMS research scientific community in Denmark

From November 22nd to November 24th 2017, Danish Research Center for Magnetic Resonance (DRCMR) will host a new TMS workshop with special focus on multimodal combinations of TMS with other neuroimaging techniques (EEG-TMS, fMRI-TMS). 

DRCMR is located in Hvidovre Hospital, a university hospital located at 9 km from Copenhagen which is administered by the Capital Region of Denmark.

Neurophysiology Plus will be represented at this meeting but also during the 20th to 22nd period for a better understanding of the center facilities, protocols used and technical equipment. 

We look mostly to have a valuable and critical analysis input from the team leaded by Prof Dr Hartwig Roman Siebner on the Icelandic proposed study. 

In this proposed clinical applied research project members of Neurophysiology Unit and Neurosurgery department from Reykjavik University and National University Hospital of Iceland are trying to analyze if TMS-EEG modality can be used or not to assess functional cortical tissue and brain effective connectivity in patients with brain tumors. 

In Iceland, another simple technique, TMS motor evoked potentials (TMS-EMG) started to be used for preoperative mapping in 2016. We set and marked the position for the intraoperative direct stimulation (IONM) as in the nineties when this technique was described. 

On the beginning of November 2017 neurosurgery department was interested on this procedure of preoperative mapping with neuronavigation. Again we used the available devices and we were able to map motor hotspots of the upper limb and speech area in a healthy subject. On 28th of November the team will investigate and perform motor and speech mapping in two patients with brain tumors located in eloquent areas of the brain. It will be for the first time that neuronavigated mapping is applied and used for the Icelandic brain tumor patients.

And the question remains: Is there a reason to believe that TEPs (TMS-EEG evoked potentials) can be used to assess better the "non-eloquent" brain cortical tissue and give a better map of the non-affected brain areas in order to avoid new post-intervention neurological deficit in patients with brain tumors ?

TMS-EEG evoked potentials (TEPs) in Iceland

29th of Sept 2017 Reykjavik Iceland

TMS-EEG evoked potentials (TEP) were performed during a joint meeting of Clinical Neurophysiology Unit team (Neurophysiology Plus Iceland) and Icelandic Center of Clinical Neurophysiology from Reykjavik University.
The meeting was organized by Assist Prof Dr Paolo Gargiulo (Director of Institute of Biomedical and Neural Engineering, Reykjavik University & Landspitali) and had as participants Dr Magnús Kjartan Gíslason & MSc Thorsteinn Geirsson (NeckCare), Aron Dalin Jónasson MSc, Hildigunnur Katrinardóttir MSc & Ovidiu C. Banea MD (Neurophysiology Lab Landspitali and Reykjavik University) and Egill Axfjörður Friðgeirsson, PhD Student University of Amsterdam.

First TMS-EMG was performed to achieve the correct out of maximum TMS intensity necessary to evoke MEP into hand thenar muscles

Using 100% RMT TMS-EEG evoked potentials were recorded. This trial was performed on experimental basis within the expert team in a healthy subject who previously accepted the test. Another 15-20 voluntary healthy subjects will be tested on both TMS-EMG and TMS-EEG protocols in accordance with World Medical Association (WMA) Declaration of Helsinki, a statement of ethical principles for medical research involving human subjects.

The future joint applied science clinical study will be developed after two international specific trainings and meetings in Denmark (Nov 2017) and France (January 2018). The aim is to assess biological neural networks (BNN) in patients with brain tumors and symptomatic epilepsy as a preoperative safety assessment of the functional brain tissue and effective connectivity in order to improve actual procedures (motor  & speech mapping and fMRI) and avoid new neurological deficit. Main collaborators of this challenging Icelandic medical research and clinical study are Neurosurgery Department of National University Hospital of Iceland (Drs Ingvar Hakon Ólafsson & Elfar Ulfarsson) and Neurosurgery Department of del Mar Hospital Barcelona, Spain (Dr Gerard Conesa). Scientific support and research specific feedback is given by Dr Eric Wassermann (NINDS/NIH; Bethesda, United States) and Prof Dr Elías Ólafsson (Head of Neurology Department, National University Hospital of Iceland).