gms | German Medical Science

55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e. V. (DGNC)
1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

25. bis 28.04.2004, Köln

Diffusion tensor imaging for preoperative planning of neurosurgical procedures: Preliminary results

Diffusions-Tensor-Bildgebung zur präoperativen Planung neurochirurgischer Eingriffe: vorläufige Ergebnisse

Meeting Abstract

  • corresponding author Ralf Steinmeier - Department of Neurosurgery, University Hospital "Carl Gustav Carus", Dresden
  • H. Kitzler - Department of Neuroradiology, University Hospital "Carl Gustav Carus", Dresden
  • A. Werner - Department of Neuroradiology, University Hospital "Carl Gustav Carus", Dresden
  • M. Dymora - Department of Neurosurgery, University Hospital "Carl Gustav Carus", Dresden
  • R. von Kummer - Department of Neuroradiology, University Hospital "Carl Gustav Carus", Dresden

Deutsche Gesellschaft für Neurochirurgie. Ungarische Gesellschaft für Neurochirurgie. 55. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), 1. Joint Meeting mit der Ungarischen Gesellschaft für Neurochirurgie. Köln, 25.-28.04.2004. Düsseldorf, Köln: German Medical Science; 2004. DocMO.09.03

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/dgnc2004/04dgnc0091.shtml

Veröffentlicht: 23. April 2004

© 2004 Steinmeier et al.
Dieser Artikel ist ein Open Access-Artikel und steht unter den Creative Commons Lizenzbedingungen (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.de). Er darf vervielf&aauml;ltigt, verbreitet und &oauml;ffentlich zug&aauml;nglich gemacht werden, vorausgesetzt dass Autor und Quelle genannt werden.


Gliederung

Text

Objective

Preoperative planning is an important issue in the resection of brain tumors located in the vicinity of the motor strip or corticospinal tract. Low grade gliomas are known to infiltrate these structures still not disturbing their functional integrity. Thus, the preoperative visualization of these highly eloquent structures in relation to the tumor plays a key role in preventing additional postoperative morbidity. Whereas the motor strip may be localized using fMRI, diffusion tensor imaging offers new possibilities of visualizing deeply located fiber tracts. The aim of the present work is to show the usefulness of integrating preoperatively measured Diffusion Tensor Imaging (DTI) data into neurosurgical planning in so far as DTI provides information about orientation, shape and connectivity of neuronal fiber pathways.

Methods

All measurements were performed on a 1.5 Tesla whole body scanner (MAGNETOM Sonata, Siemens Medizintechnik AG, Erlangen), using a circular polarized head coil. We used a conventional diffusion weighted echo planar imaging sequence (dti_ep2d_diff) with the following parameters: TR/TE: 4000/129 ms; FOV: 230x230 mm; slice thickness: 2 mm; matrix: 1282; EPI-factor: 128; 6 directions of diffusion; single b-value (750; 1000). Postprocessing was performed with the "DTI-Task-Card" (Version 1.63, MGH-NMR-Center, Boston, USA) on a „Leonardo" workstation (Siemens Medizintechnik AG, Erlangen). This tool enables the calculation and visualization of diffusion tensor maps as well as a white matter fiber tracking from the original diffusion data. An independent (blinded) observer classified the anisotropic maps and results of fiber tracking according to the following criteria: edema, infiltration, displacement, and disruption of the corticospinal tract.

Results

18 patients with tumors located near the presumed corticospinal tract underwent preoperative DTI-neuroimaging: 8 patients with a glioblastoma, 2 patients with an astrocytoma WHO grade III, 2 with an oligoastrocytoma, 3 with a grade II astrocytoma, one with a pilocytic astrocytoma, and two with a meningeoma. We found a disruption of the corticospinal tract in 4 patients with a glioblastoma and one patient with a grade III astrocytoma, all of them having a severe hemiparesis. Two additional patients (one patient with a grade III astrocytoma, one with a meningeoma) had a displacement and also showed a paresis. One patient had no pathological findings, but had a hemiparesis.

Conclusions

Our results indicate a clinically reliable visualization of fiber tracts by DTI-imaging. The visualization of fiber tracts neighboring or passing through tumor tissue was estimated to be helpful for presurgical planning in most cases. Although diffusion tensor imaging and diffusion tensor maps for visualization of fiber tracts still requires final clinical validation, and the influence of tumor infiltration and edema is still unknown, DTI potentially offers an important clinical tool for presurgical visualization of eloquent brain structures.

We would like to thank G. Sorensen, M.D., NMR-Center, Massachusetts General Hospital, Boston, USA, and Siemens Medizintechnik AG, Erlangen, for providing the DTI-Task-Card.