Establishing criteria for pediatric epilepsy surgery center levels of care: Report from the ILAE Pediatric Epilepsy Surgery Task Force.

Presurgical evaluation and surgery in the pediatric age group are unique in challenges related to caring for the very young, range of etiologies, choice of appropriate investigations, and surgical procedures. Accepted standards that define the criteria for levels of presurgical evaluation and epilepsy surgery care do not exist. Through a modified Delphi process involving 61 centers with experience in pediatric epilepsy surgery across 20 countries, including low-middle- to high-income countries, we established consensus for two levels of care. Levels were based on age, etiology, complexity of presurgical evaluation, and surgical procedure. Competencies were assigned to the levels of care relating to personnel, technology, and facilities. Criteria were established when consensus was reached (≥75% agreement). Level 1 care consists of children age 9 years and older, with discrete lesions including hippocampal sclerosis, undergoing lobectomy or lesionectomy, preferably on the cerebral convexity and not close to eloquent cortex, by a team including a pediatric epileptologist, pediatric neurosurgeon, and pediatric neuroradiologist with access to video-electroencephalography and 1.5-T magnetic resonance imaging (MRI). Level 2 care, also encompassing Level 1 care, occurs across the age span and range of etiologies (including tuberous sclerosis complex, Sturge-Weber syndrome, hypothalamic hamartoma) associated with MRI lesions that may be ill-defined, multilobar, hemispheric, or multifocal, and includes children with normal MRI or foci in/abutting eloquent cortex. Available Level 2 technologies includes 3-T MRI, other advanced magnetic resonance technology including functional MRI and diffusion tensor imaging (tractography), positron emission tomography and/or single photon emission computed tomography, source localization with electroencephalography or magnetoencephalography, and the ability to perform intra- or extraoperative invasive monitoring and functional mapping, by a large multidisciplinary team with pediatric expertise in epilepsy, neurophysiology, neuroradiology, epilepsy neurosurgery, neuropsychology, anesthesia, neurocritical care, psychiatry, and nursing. Levels of care will improve safety and outcomes for pediatric epilepsy surgery and provide standards for personnel and technology to achieve these levels.

Management of Adult Onset Seizures.

Epilepsy is a common yet heterogeneous disease. As a result, management often requires complex decision making. The ultimate goal of seizure management is for the patient to have no seizures and no considerable adverse effects from the treatment. Antiepileptic drugs are the mainstay of therapy, with more than 20 medications currently approved in the United States. Antiepileptic drug selection requires an understanding of the patient's epilepsy, along with consideration of comorbidities and potential for adverse events. After a patient has failed at least 2 appropriate antiepileptic drugs, they are determined to be medically refractory. At this time, additional therapy, including dietary, device, or surgical treatments, need to be considered, typically at a certified epilepsy center. All these treatments require consideration of the potential for seizure freedom, balanced against potential adverse effects, and can have a positive effect on seizure control and quality of life. This review article discussed the treatment options available for adults with epilepsy, including medical, surgical, dietary, and device therapies.

Modified Anterior Temporal Lobectomy: Anatomical Landmarks and Operative Technique.

There is great controversy about which surgical approach is the most selective and efficient for resection of mesial structures of the temporal lobe for treatment of mesial temporal lobe epilepsy. Selective approaches have been described in an attempt to preserve the neocortex and the temporal stem. Nonselective approaches, such as anterior temporal lobectomy (ATL), result in injuries in these structures. We describe a modified selective technique for resection of the amygdala and hippocampus with resection of the temporal pole performed through the Sylvian fissure based on anatomical landmarks and diligent microsurgical techniques. Briefly, after opening the Sylvian fissure, the temporal pole is resected and the temporal horn is directly accessed through the uncus, in an anteroposterior direction, preserving the temporal stem and the neocortex of the temporal lobe. The surgical technique used by our group is described in detail with illustrations. Precise microsurgical techniques associated with knowledge of microsurgical anatomy are of paramount importance for temporal lobe epilepsy surgery. According to our analysis, the modified ATL approach to the temporal mesial structures is a feasible selective technique that can be used as an alternative to traditional surgical procedures.

Clinical curative effect analysis and predictors of prognosis in patients with temporal lobe epilepsy after anterior temporal lobectomy: results after five years.

BACKGROUND: Anterior temporal lobectomy (ATL) is the most common surgical treatment for temporal lobe epilepsy (TLE), although long-term prognosis is often less favorable than short-term outcomes. This study aimed to examine the outcomes of patients with TLE 5 years after undergoing ATL, and to seek possible predictors of prognosis. METHODS: We examined the clinical records of 121 patients with TLE who underwent ATL in our institution between January 2005 and December 2008. The Engel seizure classification was used to divide patients into "seizure free" and "non-seizure free" groups. Univariate and multivariate Logistic regression analyses were used to identify potential prognostic indicators, including history, clinical features of seizures, and magnetic resonance imaging (MRI) and video-electroencephalography (EEG) findings. RESULTS: The majority of patients were seizure free during the follow-up period: 71.9% 1 year after surgery; 71.6% after 2 years; 75.8% after 3 years; 78.8% after 4 years after surgery and 68.8% after 5 years. There were significant differences between seizure-free and non-seizure-free groups in terms of preoperative seizure duration, history of febrile seizures, type of seizure, and MRI and video-EEG findings (P < 0.05), but not in terms of sex, age at seizure onset, age at surgery, side of surgery, auras, family history of seizure, or history of traumatic brain injury, perinatal anoxia or intracranial infection history (P > 0.05). Multivariate Logistic regression analysis showed that a preoperative seizure duration <10 years, a history of febrile seizures, simple complex partial seizures, positive MRI findings, hippocampal sclerosis and unilateral localized video-EEG spikes predicted better outcome (P < 0.05). CONCLUSIONS: ATL appears to be an effective means of treating TLE. Patients undergoing ATL for TLE require careful and comprehensive assessment to ensure optimal outcomes and to allow patients to make informed decisions about their treatment.

Selective amygdalohippocampectomy versus anterior temporal lobectomy in the management of mesial temporal lobe epilepsy: a meta-analysis of comparative studies.

OBJECT: Whether selective amygdalohippocampectomy (SelAH) has similar seizure outcomes and better neuropsychological outcomes compared with anterior temporal lobectomy (ATL) is a matter of debate. The aim of this study was to compare the 2 types of surgery with respect to seizure outcomes and changes in IQ scores. METHODS: PubMed, Embase, and the Cochrane Library were searched for relevant studies published between January 1990 and September 2012. Studies comparing SelAH and ATL with respect to seizure and intelligence outcomes were included. Two reviewers assessed the quality of the included studies and independently extracted the data. Odds ratios and standardized mean deviations with 95% confidence intervals were used to compare pooled proportions of freedom from seizures and changes in IQ scores between the SelAH and ATL groups. RESULTS: Three prospective and 10 retrospective studies were identified involving 745 and 766 patients who underwent SelAH and ATL, respectively. The meta-analysis demonstrated a statistically significant reduction in the odds of seizure freedom for patients who underwent SelAH compared with those who underwent ATL (OR 0.65 [95% CI 0.51-0.82], p = 0.0005). The differences between the changes in all IQ scores after the 2 types of surgery were not statistically significant, regardless of the side of resection. CONCLUSIONS: Selective amygdalohippocampectomy statistically reduced the odds of being seizure free compared with ATL, but the clinical significance of this reduction needs to be further validated by well-designed randomized trials. Selective amygdalohippocampectomy did not have better outcomes than ATL with respect to intelligence.

Seizure types and frequency in patients who "fail" temporal lobectomy for intractable epilepsy.

BACKGROUND: Temporal lobectomy can lead to favorable seizure outcomes in medically-refractory temporal lobe epilepsy (TLE). Although most studies focus on seizure freedom after temporal lobectomy, less is known about seizure semiology in patients who "fail" surgery. Morbidity differs between seizure types that impair or spare consciousness. Among TLE patients with seizures after surgery, how does temporal lobectomy influence seizure type and frequency? OBJECTIVE: To characterize seizure types and frequencies before and after temporal lobectomy for TLE, including consciousness-sparing or consciousness-impairing seizures. METHODS: We performed a retrospective longitudinal cohort study examining patients undergoing temporal lobectomy for epilepsy at our institution from January 1995 to August 2010. RESULTS: Among 241 TLE patients who received temporal lobectomy, 174 (72.2%) patients achieved Engel class I outcome (free of disabling seizures), including 141 (58.5%) with complete seizure freedom. Overall seizure frequency in patients with persistent postoperative seizures decreased by 70% (P < .01), with larger reductions in consciousness-impairing seizures. While the number of patients experiencing consciousness-sparing simple partial seizures decreased by only 19% after surgery, the number of individuals having consciousness-impairing complex partial seizures and generalized tonic-clonic seizures diminished by 70% and 68%, respectively (P < .001). Simple partial seizure was the predominant seizure type in 19.1% vs 37.0% of patients preoperatively and postoperatively, respectively (P < .001). Favorable seizure outcome was predicted by a lack of generalized seizures preoperatively (odds ratio 1.74, 95% confidence interval 1.06-2.86, P < .5). CONCLUSION: Given important clinical and mechanistic differences between seizures with or without impairment of consciousness, seizure type and frequency remain important considerations in epilepsy surgery.

Epilepsy surgery in patients with unilateral mesial temporal sclerosis and contralateral scalp ictal onset.

AIM: Concordance of EEG findings and MRI is best correlated with favored surgical outcome in patients with unilateral mesial temporal sclerosis (MTS). If there is no evidence for unilateral focus with scalp EEG, invasive recordings are undertaken. In this report we describe the investigation process for epilepsy surgery in patients with unilateral MTS and contralateral ictal scalp EEG findings. MATERIAL AND METHODS: The data of all adult patients who had undergone videoEEG recording with subdural and/or depth electrodes at our center in almost 7.5 years, were reviewed. Four patients with unilateral MTS and contralateral ictal onset on scalp EEG were included. Their invasive EEG recordings and surgical outcomes were examined. RESULTS: Four patients met the inclusion criteria. Invasive recordings demonstrated ictal onset in the mesial temporal lobe ipsilateral to MRI findings. In one patient we have also proven the false lateralization of scalp EEG simultaneously during the recordings with depth electrodes. All operated cases are seizure free during follow-up. CONCLUSION: Before the decision of epilepsy surgery we have to identify the semiology and ictal EEG findings in patients with unilateral MTS and concordant IEDs. Bilateral depth recordings must be considered to show the ipsilateral hippocampal epileptogenic focus.

Prognostic value of concordant seizure focus localizing data in the selection of temporal lobectomy candidates.

This study was performed to test the hypotheses that (a) resection of the temporal lobe epileptic focus, amenable to noninvasive as opposed to invasive localization, is associated with superior seizure outcome and (b) that quadruple (versus lesser degrees of) concordance of seizure focus localizing data predicts superior seizure-free outcome. Eighty-three patients underwent invasive (subdural-EEG) and/or noninvasive (video/scalp-EEG, SPECT, PET, MRI, neuropsychological testing) evaluation. All patients underwent anterior temporal lobectomy and amygdalohippocampectomy (ATL/AH) and seizure outcome was assessed at minimum one-year follow-up. At 34.8 +/- 2.5 months following ATL/AH, outcome was superior for patients in whom the seizure focus was amenable to noninvasive compared to invasive localization (80% versus 40% seizure-free, X2 = 14.03, p < 0.05). Seizure outcome was superior for patients with quadruple, compared to all lesser degrees of, concordance of seizure focus localizing data (85% versus 51% seizure-free, X2 = 7.34, p < 0.05). Post-ATL/AH, seizure outcome is superior in patients (1) harboring an epileptic focus amenable to noninvasive localization and (2) with quadruple concordance of seizure focus localizing data. These findings support the development of temporal lobectomy selection criteria including up to four invasive and/or noninvasive concordant seizure focus localizing techniques.