MRI predictive score of pial vascularization of supratentorial intracranial meningioma.

OBJECTIVE

Meningiomas are highly vascularized tumors which may recruit pial blood supply. Pial supply complicates tumor treatment in numerous ways. The objective of this study was to establish a reliable MRI-based diagnostic score to predict the existence of pial blood supply in supratentorial intracranial meningiomas and then correlate the score with clinical and surgical outcomes and histopathological findings.

METHODS

We performed a retrospective analysis of supratentorial histologically proven meningiomas in our institution from 2010 to 2018. A score was built based on MRI criteria and correlated with digital subtraction angiography (DSA) pial vascularization assessment. The score was then validated on a second independent population recruited with the same modalities.

RESULTS

Logistic regression identified four parameters related to pial blood supply which were used to build the score: skull base location, tumor size > 45 mm, peritumoral flow voids, and incomplete cerebrospinal fluid rim. The overall diagnostic performance in predicting pial blood supply was as follows: sensitivity 97.8%, specificity 76.9%, predictive positive value 88.2%, negative predictive value 95.2%, and accuracy 90.3%. Inter-reader agreement and Cohen's kappa were good, respectively, of 90.7% and 0.69. A high score was associated with aggressive meningioma (World Health Organization II-III) (p = 0.04) and with greater importance of pial supply relative to dural supply.

CONCLUSIONS

We have identified a reliable way to use MRI to predict the existence of pial blood supply in supratentorial intracranial meningiomas. A higher score also predicted higher grade meningioma.

KEY POINTS: • Accurate and reproducible MRI score composed of four items to predict the existence of pial blood supply in supratentorial meningioma. • High score is associated with high-grade meningioma (WHO II-III) but also with greater importance of pial supply relative to dural supply.