gms | German Medical Science

63rd Annual Meeting of the German Society of Neurosurgery (DGNC)
Joint Meeting with the Japanese Neurosurgical Society (JNS)

German Society of Neurosurgery (DGNC)

13 - 16 June 2012, Leipzig

Ultra-high field 7T fMRI for preoperative localization of eloquent brain areas

Meeting Abstract

  • K.H. Wrede - Klinik für Neurochirurgie, Universitätsklinikum Essen; Erwin L. Hahn Institut für Magnetresonanz, Essen
  • P. Damman - Klinik für Neurochirurgie, Universitätsklinikum Essen
  • C.F. Beckmann - Donders Centre for Cognitive Neuroimaging, Nijmegen, Netherlands
  • M.E. Ladd - Erwin L. Hahn Institut für Magnetresonanz, Essen; Institut für Diagnostische und Interventionelle Radiologie und Neuroradiologie, Universitätsklinikum Essen
  • U. Sure - Klinik für Neurochirurgie, Universitätsklinikum Essen
  • T. Gasser - Klinik für Neurochirurgie, Universitätsklinikum Essen

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 63. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie (JNS). Leipzig, 13.-16.06.2012. Düsseldorf: German Medical Science GMS Publishing House; 2012. DocFR.14.05

DOI: 10.3205/12dgnc293, URN: urn:nbn:de:0183-12dgnc2933

Published: June 4, 2012

© 2012 Wrede et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

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Objective: Preoperative brain mapping has an impact on the surgical strategy in patients with lesions in or close to eloquent brain areas. fMRI profits from higher field strengths due to an enhanced SNR. The goal of this study was to set up a 7T examination protocol for preoperative brain mapping using resting state fMRI.

Methods: A 7T whole-body system equipped with a 32-channel Rx/Tx head coil was employed for image acquisition. For BOLD fMRI we used an optimized 7T 3D EPI sequence. Anatomical images were acquired with a modified MPRAGE sequence (voxel size=0.7 mm3). Analysis of the preprocessed resting state data (400 time points) was carried out using Multivariate Exploratory Linear Optimized Decomposition into Independent Components. In addition, a regression technique was applied to the resting state data utilizing a previously described resting state network as reference template. All subjects also performed sequential finger tapping of the right and left hand. The preprocessed block design functional data (105 time points) was analyzed using FMRI Expert Analysis Tool.

Results: For the study 10 healthy volunteers (age range=23–38 years; male=5, female=5) were scanned. Block design finger tapping fMRI showed robust activation of the contralateral sensorimotor cortex and the ipsilateral cerebellum in all subjects. In the 60 IC maps returned by the ICA, the sensorimotor network (SMN) and the default-mode network (DMN) could be clearly depicted in all subjects. Other previously described resting state networks could be depicted in 8 subjects. The IC map representing the sensorimotor network showed excellent correlation to the anatomical structures. The regression analysis of the resting state data revealed reasonable results for the 8 resting state networks of the template. The overall rating of the acquired data and activations were rated acceptable and helpful for surgical decisions by the two independent experienced neurosurgeons.

Conclusions: We present a 7T fMRI protocol for preoperative brain mapping, eligible for patients with brain lesions in or close to eloquent brain areas. In a subsequent study, brain mapping data derived from direct cortical electrical stimulation, will be correlated to the preoperative fMRI for verification of the fMRI data.