Haemangioma, an uncommon cause of an extradural or intradural extramedullary mass: case series with radiological pathological correlation

UNLABELLED Haemangiomas of the vertebrae, usually regarded as having little or no consequence, may display aggressive features, including extension into the extradural space, and cause significant neurological symptoms and signs necessitating treatment. Extraosseous haemangiomas in an extradural or intradural extramedullary location are a rare entity. Here we review our radiologic and pathologic experience of osseous haemangiomas with extradural extension and primary extradural and intradural extramedullary haemangiomas. Magnetic resonance imaging plays a pivotal role in the characterisation of spinal haemangiomas, with typical imaging features including T1 and T2 signal hyperintensity. Atypical and aggressive imaging features are also described. Spinal angiography may be required to differentiate haemangiomas from non-vascular lesions. This is a rare and unusual entity, and should be considered as a differential diagnosis for some extramedullary masses. TEACHING POINTS • Osseous haemangiomas can display aggressive features and cause neurologic symptoms needing treatment. • Haemangioma extension into the extradural space is an imaging feature of aggressiveness. • Extraosseous haemangiomas are a rare but important differential diagnosis for extramedullary masses. • Extraosseous extramedullary haemangiomas most frequently present with progressive myelopathy. • MRI is pivitol in characterising spinal haemangiomas; imaging characteristics can vary.