Vascular Malformations and Epilepsy: Clinical Considerations and Basic Mechanisms

Abstract

Vascular malformations (VMs) are associated with epilepsy. The natural history of the various VMs, clinical presentation, and tendency to provoke epilepsy determine treatment strategies. Investigations have probed the mechanisms of epileptogenesis associated with these lesions. Electrophysiologic changes are associated with epileptogenic cortex adjacent to VMs. Putative pathophysiologic mechanisms of epileptogenesis include neuronal cell loss, glial proliferation and abnormal glial physiology, altered neurotransmitter levels, free radical formation, and aberrant second messenger physiology.

Surgical management and long-term outcome of pediatric patients with different subtypes of epilepsy associated with cerebral cavernous malformations

“…4 Patients with longstanding epilepsy in particular may benefit from detailed epileptological evaluation, since in those cases it is known that remote epileptogenic foci can develop. 15,28 It has been shown in adult patients that virtually all patients who experience a first seizure associated with a CCM will develop epilepsy in a 5-year follow-up period.…”

Cerebral cavernous malformations and epilepsy

“…Of patients who harbor a single CCM, undergo lesionectomy for treatment of recent-onset, localization-related seizures, and are seizure free postoperatively, up to half may successfully taper off all anticonvulsant medications. 21,35,64,69 This promising outcome, and its associated positive impact on quality of life, may play a role in the decision to excise a solitary accessible cortical CCM, even when seizures are not truly intractable to medical therapy.…”

“…26 Morphological changes have also been identified, including alterations in vascular supply, neuronal cell loss, glial proliferation, and subtle subcortical disconnections. 35 It is commonly believed that the breakdown products caused by repeated microhemorrhages deposit ferric ions, which are known to be highly epileptogenic, into the cortex around the lesion. In animals, the injection of ferric ions into the cortex and subcortical regions creates a potent and reproducible model of recurrent and intractable seizures.…”

Epileptogenicity of a patient with the association of medullary venous malformation and cavernous malformation

“…Among vascular malformations, AVM and CM are well known to be highly epileptogenic [2], but the epileptogenicity of MVM remains controversial [3,4,5,6]. The reason for this may be attributed to the complicated pathology of MVM, because MVM is sometimes associated with other epileptogenic vascular malformations [7].…”