ESTRO 2025 - Abstract Book

S767

Clinical - CNS

ESTRO 2025

4507

Digital Poster QSM Mapping Reveals Unique Vascular Signatures in Different Glioma Subtypes

Najmus S Iqbal 1 , Eleonora Patitucci 2 , Stefano Zappala 2 , James Powell 1 , Richard Wise 3,4 , Michael Germuska 5,6 1 Clinical Oncology, Velindre University NHS Trust, Cardiff, United Kingdom. 2 Cardiff University Brain Research Imaging Centre, Cardiff University, Cardiff, United Kingdom. 3 Department of Neurosciences, Imaging, and Clinical Sciences, University ‘G. D’Annunzio’ of Chieti-Pescara, Chieti, Italy. 4 Institute for Advanced Biomedical Technologies, University ‘G. D'Annunzio’ of Chieti-Pescara, Chieti, Italy. 5 CUBRIC & School of Physics and Astronomy, Cardiff University, Cardiff, United Kingdom. 6 Department of Radiology, University of California Davis Medical Centre, Sarcramento, USA Purpose/Objective: The brain’s normal vasculature is affected in gliomas due to the need for an increased blood supply to provide additional nutrients and oxygen required for tumour growth. Vascular proliferation is a pathological hallmark of gliomas, and heterogeneity of vascular morphology is present in gliomas, with astrocytic gliomas presenting high micro vessel density and high-grade tumours exhibiting a significant degree of neovascularization. Here, we used quantitative susceptibility mapping(QSM) to detect differential vascular characteristics in glioma subtypes. QSM images magnetic susceptibility variations quickly without the need for administration of a contrast agent. QSM maps estimates quantitative measures of oxygen extraction fraction (OEF), vascular density, and vessel diameter. We hypothesise that QSM maps will be sensitive to detect alterations in vascular parameters between tumour subtypes. Material/Methods: Patients with a diagnosis of glioma underwent MRI scanning including and pre-/post-contrast T1-weighted, T2 weighted, and T2FLAIR images. HD-Glio automated segmentation tool was used for identifying tumour and oedema. Vessels were segmented on QSM; and vessel diameter, density and OEF were calculated. ANOVA was used to assess differences in OEF, vessel diameter, and vascular density in oedema and residual healthy grey matter among glioma subtype and WHO grade.

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