gms | German Medical Science

70. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Skandinavischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

12.05. - 15.05.2019, Würzburg

Integrity of (b)lood-(o)xygen-(l)evel)-(d)ependent signal of language associated brain activation depending on tumour proximity and radiological tumour growth patterns in patients with glioblastoma

Die Integrität von sprachassoziiertem (b)lood-(o)xygen-(l)evel)-(d)ependent-Signal in Abhängigkeit von Tumornähe und radiolgischem Tumor-Wachstumsmuster bei Patienten mit Glioblastomen

Meeting Abstract

  • presenting/speaker Katharina Rosengarth - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Katharina Hense - Universität Regensburg, Experimentelle Psychologie, Regensburg, Deutschland
  • Isabel Wiesinger - Universität Regensburg, Radiologie, Regensburg, Deutschland
  • Christian Ott - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Christian Doenitz - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Alexander Brawanski - Universitätsklinikum Regensburg, Klinik und Poliklinik für Neurochirurgie, Regensburg, Deutschland
  • Christina Wendl - Universität Regensburg, Radiologie, Regensburg, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 70. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Skandinavischen Gesellschaft für Neurochirurgie. Würzburg, 12.-15.05.2019. Düsseldorf: German Medical Science GMS Publishing House; 2019. DocP050

doi: 10.3205/19dgnc388, urn:nbn:de:0183-19dgnc3881

Published: May 8, 2019

© 2019 Rosengarth et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Text

Objective: Functional magnetic resonance imaging (fMRI) in glioblastoma (GBM) is challenging because these tumors exhibit an impaired neurovascular coupling which decreases fMRI signal and may lead to misinterpretations of fMRI signals. In this study we wanted to investigate if a radiologically defined tumor growth pattern may influence the integrity of the fMRI signal and interact with tumor proximity in patients suffering from GBM.

Methods: 30 patients with primary GBM were included. Patients were stratified in 2 groups according to their radiologically defined tumor growth pattern. Tumors were either displacing (D-GBM; 11 patients) or infiltrating (I-GBM; 19 patients). Functional imaging was performed at a 3T Siemens Scanner. During the fMRI paradigm subjects had to perform covertly a verb generation task. Data analysis was done by using SPM 12 including the Marsbar toolbox for region of interest (ROI) definition and analysis. To assess the influence of tumor proximity and growth pattern on (language associated) fMRI-signal integrity percent signal change and finite impulse response functions in four ROIs were defined located one proximate, one peripheral and two distal (one tumor ipsilateral and one tumor contralateral) to the tumor. Results were adjusted for tumor size, necrosis size and age.

Results: Qualitatively, percent signal changes showed reasonable values in all ROIS independently of their location (min=0.3% max=1.7%) but appearing generally lower proximal to a tumor. Similarly, the integrals of the FIR-functions were lower in ROIs close to a tumor compared to ROIs distal to a tumor. Independently of tumor growth pattern fMRI signal was significantly lower in ROIs which were proximate and peripheral to a tumor compared to ROIs located distal to a tumor. The comparison of tumor proximate and tumor peripheral fMRI- signal revealed that only D-GBM patients showed significant higher fMRI-signals in the peripheral ROI. This was not significantly apparent in patients with I-GBMs. According to FIR-signals there were significantly lower integrals for ROIs close to a tumor than in ROIs distal to a tumor in the group with I-GBMs which was not present in the group with D-GBMs presumably reflecting a higher fMRI signal integrity in this group.

Conclusion: Preliminary results suggest that fMRI signal is still valid in proximity of a tumor but is among other factors influenced by radiologically defined tumor growth pattern.