NIMG-02. STRAIN ELASTOGRAPHY: INTRA-OPERATIVE BRAIN TUMOUR CARACHTERIZATION

Abstract

BACKGROUND: Sonoelastography is an ultrasound imaging technique able to assess mechanical properties of tissues. Strain elastography (SE) is qualitative sonoelastographic modality with a wide range of clinical applications, but its use in brain tumor surgery is very limited. OBJECTIVE: We describe the first large-scale implementation of SE in oncological neurosurgery for lesions discrimination and characterization. METHODS: We analyzed retrospective data from 64 patients aiming at (i) evaluating the stiffness of the lesion and of the surrounding brain, (ii) assessing the correspondence between B- mode and SE, and (iii) performing subgroup analysis for gliomas characterization RESULTS: i) In all cases we visualized the lesion and the surrounding brain with SE, permitting a qualitative stiffness assessment. ii) In 90% of cases, lesion representations in B-mode and SE were superimposable with identical morphology and margins. In 64% of cases lesion margins were sharper in SE than in B-mode. iii) In 76% of cases, glioma margins were sharper in SE than in B-mode. Lesions morphology/ dimensions in SE and in B-mode were superimposable in 89%. Low grade (LGG) and high grade (HGG) gliomas were significantly different in terms of lesion stiffness, stiffness of the surrounding brain, and stiffness contrast between tumours and brain, LGG appearing stiffer while HGG softer than brain (all p CONCLUSION: SE allows to understand mechanical properties of the brain and lesions in exam and permits a better discrimination between different tissues compared to B-mode. Additionally, SE can differentiate between LGG and HGG.