Appearance of a cavernous hemangioma in the cerebral cortex after a biopsy of a deeper lesion.

Cavernous hemangiomas are vascular malformations that can occur throughout the central nervous system. In certain patients, multiple lesions are known to occur. We present a patient with multiple cavernous hemangiomas who had a computed tomography-guided biopsy of a deep parieto-occipital lesion through a burr hole. Several passes of a biopsy needle were used. During a 5-year interval, the patient developed a new lesion directly under the burr hole on the cortical surface. The new lesion appears to have occurred from the implantation and growth of a cavernous hemangioma secondary to the biopsy.