Practice Parameter: Temporal Lobe and Localized Neocortical Resections for Epilepsy

Abstract

Summary:Purpose: To examine evidence for effectiveness of anteromesial temporal lobe and localized neocortical resections for disabling complex partial seizures.Methods: Systemic review and analysis of the literature since 1990.Results: One intention-to-treat Class I randomized controlled trial of surgery for mesial temporal lobe epilepsy found that 58% of patients randomized to be evaluated for surgical therapy (64% of those who received surgery) were free of disabling seizures and 10 to 15% were unimproved at the end of 1 year, compared with 8% free of disabling seizures in the group randomized to continued medical therapy. There was a significant improvement in quantitative quality-of-life scores and a trend toward better social function at the end of 1 year for patients in the surgical group, no surgical mortality, and infrequent morbidity.Twenty-four Class IV series of temporal lobe resections yielded essentially identical results. There are similar Class IV results for localized neocortical resections; no Class I or II studies are available.Conclusions: A single Class I study and 24 Class IV studies indicate that the benefits of anteromesial temporal lobe resection for disabling complex partial seizures is greater than continued treatment with antiepileptic drugs, and the risks are at least comparable. For patients who are compromised by such seizures, referral to an epilepsy surgery center should be strongly considered. Further studies are needed to determine if neocortical seizures benefit from surgery, and whether early surgical intervention should be the treatment of choice for certain surgically remediable epileptic syndromes.

Excessively elevated C-reactive protein after surgery for temporal lobe epilepsy

“…Surgical complications in our series including neurological morbidity and perioperative surgical complications were comparable to the literature review by Engel et al [15].…”

“…In the surgery group of this trial, 58% of the patients were free of disabling seizures at the end of 1 year, 38% were free of all seizures including auras, 10%-15% had little or no improvement compared to 8% being free of disabling seizures in the medical group [1]. Clinical outcome after surgery for temporal lobe epilepsy has also been extensively reviewed by Engel et al [15]. Seizure outcome after anteromesial temporal lobe resections (not differentiating between SAH and tailored anterior temporal lobe resections) of 21 retrospective analyses yielded 1769 patients of whom 1150 (65%) were free of disabling seizures, 372 (21%) were improved, and 347 (14%) were not improved.…”

Epileptiform synchronization in the rat insular and perirhinal cortices in vitro

“…(Engel, 2001;Engel et al, 2003). Surgical intervention is becoming the best alternative for these patients, since up to 80%…”

“…of TLE patients become seizure-free with resection of temporal structures (Engel, 2001;Wiebe et al, 2001;Engel et al, 2003;Cohen-Gadol et aL, 2006). While unilateral removal of hippocampal and amygdalar structures is often sufficient and successful, there is evidence that seizures originating within extrahippocampal structures may account for the lack of success in the remaining 20% that do not respond to surgery (Ryvlin and Kahane, 2005).…”

Cortical abnormalities in epilepsy revealed by local EEG synchrony

“…Resective epilepsy surgery for refractory seizures targets the epileptogenic zone, the minimum region of cortex whose removal is both necessary and sufficient to abolish seizures (Luders and Awad 1991;Engel 2003). Analysis of intracranial EEG (ICEEG) ictal recordings to identify the epileptogenic zone is generally more specific than information provided by seizure semiology, neuroimaging or neuropsychological testing (Engel, Henry et al 1990).…”