Discussion the WHO grading of brain invasion otherwise benign meningiomas (BIOB) from the MR images perspective of 675 meningiomas

Should the BIOB meningiomas be classified as WHO grade 1 or WHO grade 2 atypical meningiomas, the core issue that scholars have questioned about the guidelines from an imaging perspective. In this study, we used BIOB as the entry point to comprehensively compare and analyze the MRI imaging characteristics of BIOB between WHO grade 1 and 2 meningiomas. Comparative analysis of multiple groups of MRI characteristics showed that BIOB and WHO grade 2 meningiomas were more similar in clinical and imaging features than grade 1 meningiomas. Therefore, it is reasonable to classify BIOB as WHO grade 2 meningiomas in the guidelines.