Computed tomography and magnetic resonance appearance of sporadic meningioangiomatosis correlated with pathological findings.

PURPOSE: Meningioangiomatosis (MA) is a rare benign localized lesion of leptomeninges and underlying cerebral cortex. Preoperative diagnosis is difficult and challenging because of its diverse clinical, pathological, and imaging features. We retrospectively analyzed 7 cases of MA to explore their imaging features and correlate with pathological findings.

MATERIALS AND

METHODS

Imaging studies including computed tomography (CT) and magnetic resonance imaging (MRI) were retrospectively reviewed in 7 patients with surgically and pathologically verified intracranial MA (not associated with neurofibromatosis). Computed tomography studies were performed in axial plane without iodinated contrast-material administration; magnetic resonance studies consisted of axial T1-weighted, T2-weighted, Fluid attenuated Inversion Recovery (FLAIR), and postcontrast T1-weighted sequences and coronal or sagittal precontrast and postcontrast T1-weighted sequences.

RESULTS

Computed tomography showed focal extensively calcified lesions in 3 cases, lesions with patchy calcification in 2 cases, and no apparent calcification in 2 cases. Magnetic resonance imaging demonstrated predominantly hypointensity on T1-weighted images and hyperintensity on T2-weighted images. Six of 7 cases exhibited gyriform hyperintensity on FLAIR sequences, which correlated with proliferating microvessels with perivascular cuffs of spindle-cell proliferation within the cortex on histopathological analysis. After contrast-material administration, all but 1 showed heterogeneous enhancement. The nonenhancing lesion on MRI was completely calcified on CT.

CONCLUSION

Gyriform hyperintensity on FLAIR sequence is the main MRI feature of MA, which correlates with proliferating microvessels with perivascular cuffs of spindle-cell proliferation within the cortex on pathological analysis. Plain CT scan is essential to demonstrate the extent of calcification of these lesions.