Intramedullary Spinal Cord Cavernous Malformations: Clinical Features and Surgical Management

Cavernous malformations (CMs) are thin dilated capillary-type, sinusoidal low-flow vascular malformations, without intervening neural tissue, which are prone to repeated hemorrhage and growth over time. Intramedullary spinal CMs (ISCMs) constitute a rare pathology, accounting for 5–12% of all intraspinal vascular malformations. Intramedullary spinal cord cavernous malformations tend to be clinically progressive. The incidence of initial intramedullary hemorrhage is estimated to be 2.1% patient/year, increasing to 66% in those with a previous history of hemorrhage. The annual hemorrhage and rehemorrhage rates in children are higher than in adults. It has become a reasonable consensus on early microsurgical resection, usually within 3 months, as the primary option in symptomatic patients of SCCMs that can provide good outcomes, in spite of the existing potential risk of operative neurological complication. Continuous multimodal intraoperative neurophysiological monitoring (IONM) of somatosensory evoked potentials (SSEP), motor-evoked potentials (MEP), and D-wave recording is essential to reduce the risk of surgery-related deficits by providing real-time feedback about the degree of spinal cord manipulation. An individualized surgical approach to achieve complete resection in carefully selected symptomatic patients is required to prevent further neurological decline from rebleeding.