Remote epileptogenic focus detected by electrocorticogram in a case of cavernous angioma

Abstract

In a case of cavernous angioma, a remote gyrus, which was found to contain an epileptogenic focus by intraoperative electrocorticography (ECoG), was resected simultaneously with lesionectomy. The patient was a 27-year-old male who was referred to our hospital because of frequent systemic tonic-clonic convulsions. ECoG revealed an epileptogenic focus not only in the cortex around the angioma-affected tissue of the left frontal lobe but also in an angioma-free remote gyrus. These epileptogenic foci were removed in addition to lesionectomy. The postoperative course was uneventful. Now (two years after surgery), the patient is seizure-free without any anti-convulsive agent. In the surgical treatment of convulsions-accompanied by cavernous angioma, it is essential not only to detect epileptogenic foci by intraoperative ECoG but also to remove these foci together with the angioma.

Cavernomas of the central nervous system in children

“…Otherwise we have observed a complete remission of seizure disorders also when surgery was limited to the removal of the cavernous angioma because of the absence of any follow-up MRI T2 image (8 months after surgery) confirming the complete excision of the cavernous angioma, with a hypo-intensity signal surrounding the residual cavity, referable to methaemoglobin and gliotic tissue well-defined encapsulation. Further, cortical resection was never necessary to control seizure disturbances in our patients: the removal of cavernomas was always sufficient to resolve patients convulsive problems; our observations disagree with the opinion of some authors who suggest the removal of remote epileptogenic areas simultaneously with the exstirpation of the cavernous angioma [13]; we think that, in these cases, seizures may be adequately treated by the resection of the cavernous angioma only, as it has been confirmed by other authors [12,23,24]. The postoperative disappearance of epileptic fits is probably due to a loss of hyperexcitability of the neuronal epileptogenic tissue around the cavernous angioma after its surgical removal (Fig.…”

De Novo Formation of Cerebral Cavernous Malformation in a Patient with Intractable Epilepsy: Case Report and Review

“…Surgical removal of CCMs is recommended in patients with progressive neurological symptomatology, recurrent bleeding, and intractable seizures 3,4,6 . In cases where cavernomas are encountered in patients with intractable epilepsy, delineation of the epileptogenic brain tissue is a key component of the decision‐making process for selection of optimal surgical approach 27,28 . Thorough neurophysiological assessment usually provides sufficient data for targeting the epileptogenic foci.…”

“…3,4,6 In cases where cavernomas are encountered in patients with intractable epilepsy, delineation of the epileptogenic brain tissue is a key component of the decision-making process for selection of optimal surgical approach. 27,28 Thorough neurophysiological assessment usually provides sufficient data for targeting the epileptogenic foci. At the same time, the risk of bleeding from CCM should also be taken into consideration, with current literature supporting the idea of surgical resection of CCMs as a way to reduce the risk of hemorrhage and seizures associated with them.…”

Utility of electrocorticography in the surgical treatment of cavernomas presenting with pharmacoresistant epilepsy

“…Patients with drug-resistant epilepsy secondary to CA show highly epileptiform discharge patterns on ECoG recordings, which include continuous spikes, bursts, and recruiting discharges similar to those observed in patients with neurodevelopmental lesions. ECoG recordings during CA surgery detect additional epileptiform discharges in perilesional tissues or more remotely located areas (Kamada et al, 1994), making it a very useful tool to guide the resection (Van Gompel et al, 2009). This indicates that the presence of continuous spikes in ECoG recordings of CA is associated with a long history of epilepsy before surgery.…”

“…No association between the degree of haemosiderin deposits and the ECoG patterns has been reported (Baumann et al, 2006). ECoG recordings during CA surgery detect additional epileptiform discharges in perilesional tissues or more remotely located areas (Kamada et al, 1994), making it a very useful tool to guide the resection (Van Gompel et al, 2009). The postsurgical ECoG recordings in CA surgery can guide the careful removal of any residual epileptic foci and predict the outcome (Cho et al, 2005;Sun et al, 2011); however, the value of post-resection ECoG is controversial (Sugano et al, 2007).…”