Can CT and MRI Features Differentiate Benign from Malignant Meningiomas?

Aim: To highlight magnetic resonance imaging (MRI) and computed tomography (CT) characteristics in distinguishing benign from high-grade meningiomas (World Health Organization [WHO] grade II and III) preoperatively.

Materials And Methods: Seventy-one patient who underwent surgical resection of intracranial meningiomas at American University of Beirut Medical Center between 2008 and 2017 were evaluated for various CT and MRI features. The correlation between imaging findings, histopathological grading, and operative reports was analysed via univariate and multivariate logistic regression analysis. MRI specificity and sensitivity in detecting meningioma brain invasion as compared to operative reports post-resection was detected.

Results: Univariate analysis results showed a significant correlation between high-grade meningiomas and several MRI features including tumour size and volume (p=0.002,0.02), heterogeneous enhancement (p<0.0001), presence of intra-tumoural necrosis (p<0.0001), ill-defined margin (p=0.003), bone erosion (p=0.004), brain invasion (p=0.001), and a higher rate of recurrence (p=0.007) Only brain invasion and presence of intra-tumoural necrosis were significantly correlated with the high-grade meningioma in multivariate analysis. Hyperostosis of the adjacent skull was the only significant CT feature predicting the presence of low-grade meningioma. MRI showed 79% specificity and 20% sensitivity, 92% negative predictive value and 7% positive predictive value in detecting meningioma brain invasion.

Conclusion: MRI has a promising role in predicting meningioma grade prior to resection, which can directly impact patients' management protocols regarding surgical planning and complications.