Imaging features of unusual intracranial cystic meningiomas

To describe the imaging features of unusual intracranial cystic meningiomas in infants and adults.

We retrospectively reviewed the magnetic resonance and computed tomography findings for 2 female patients and 3 male patients, ranging in age from 1 to 73 years (median 41 years), with histopathologically proven cystic meningioma.

Although cystic meningiomas usually appear as solid and cystic masses, they may present as a mainly multicystic lesion. The wall of a cystic part of the meningioma may include both enhancing and unenhancing areas at imaging. The cystic portion of a meningioma is hypointense on diffusion-weighted images and markedly hyperintense on corresponding apparent diffusion coefficient maps.

Cystic meningiomas may vary in appearance at imaging. They can be very challenging when present in infants. Knowledge of imaging findings and awareness of variability in the differential diagnosis can help to avoid preoperative diagnostic pitfalls.