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Published in: European Radiology 4/2017

Open Access 01-04-2017 | Magnetic Resonance

Local image variance of 7 Tesla SWI is a new technique for preoperative characterization of diffusely infiltrating gliomas: correlation with tumour grade and IDH1 mutational status

Authors: Günther Grabner, Barbara Kiesel, Adelheid Wöhrer, Matthias Millesi, Aygül Wurzer, Sabine Göd, Ammar Mallouhi, Engelbert Knosp, Christine Marosi, Siegfried Trattnig, Stefan Wolfsberger, Matthias Preusser, Georg Widhalm

Published in: European Radiology | Issue 4/2017

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Abstract

Objectives

To investigate the value of local image variance (LIV) as a new technique for quantification of hypointense microvascular susceptibility-weighted imaging (SWI) structures at 7 Tesla for preoperative glioma characterization.

Methods

Adult patients with neuroradiologically suspected diffusely infiltrating gliomas were prospectively recruited and 7 Tesla SWI was performed in addition to standard imaging. After tumour segmentation, quantification of intratumoural SWI hypointensities was conducted by the SWI-LIV technique. Following surgery, the histopathological tumour grade and isocitrate dehydrogenase 1 (IDH1)-R132H mutational status was determined and SWI-LIV values were compared between low-grade gliomas (LGG) and high-grade gliomas (HGG), IDH1-R132H negative and positive tumours, as well as gliomas with significant and non-significant contrast-enhancement (CE) on MRI.

Results

In 30 patients, 9 LGG and 21 HGG were diagnosed. The calculation of SWI-LIV values was feasible in all tumours. Significantly higher mean SWI-LIV values were found in HGG compared to LGG (92.7 versus 30.8; p < 0.0001), IDH1-R132H negative compared to IDH1-R132H positive gliomas (109.9 versus 38.3; p < 0.0001) and tumours with significant CE compared to non-significant CE (120.1 versus 39.0; p < 0.0001).

Conclusions

Our data indicate that 7 Tesla SWI-LIV might improve preoperative characterization of diffusely infiltrating gliomas and thus optimize patient management by quantification of hypointense microvascular structures.

Key Points

7 Tesla local image variance helps to quantify hypointense susceptibility-weighted imaging structures.
SWI-LIV is significantly increased in high-grade and IDH1-R132H negative gliomas.
SWI-LIV is a promising technique for improved preoperative glioma characterization.
Preoperative management of diffusely infiltrating gliomas will be optimized.
Appendix
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Metadata
Title
Local image variance of 7 Tesla SWI is a new technique for preoperative characterization of diffusely infiltrating gliomas: correlation with tumour grade and IDH1 mutational status
Authors
Günther Grabner
Barbara Kiesel
Adelheid Wöhrer
Matthias Millesi
Aygül Wurzer
Sabine Göd
Ammar Mallouhi
Engelbert Knosp
Christine Marosi
Siegfried Trattnig
Stefan Wolfsberger
Matthias Preusser
Georg Widhalm
Publication date
01-04-2017
Publisher
Springer Berlin Heidelberg
Published in
European Radiology / Issue 4/2017
Print ISSN: 0938-7994
Electronic ISSN: 1432-1084
DOI
https://doi.org/10.1007/s00330-016-4451-y

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