Intractable Partial Epilepsy Research Articles

Effect of magnetoencephalography on intracranial electrode placement strategy in intractable partial epilepsy

Objective To study whether magnetoencephalography (MEG) could indicate intracranial electroencephalography(icEEG) by affecting electrode placement and localization of the seizure onset zone,and then improve the curative effect of the surgical patients of refractory partial epilepsy.Methods Of all consecutive epilepsy surgery candidates between 2009 -2010,83 cases who meet the refractory partial epilepsy diagnostic criteria were prospectively enrolled in this research.The 83 patients were randomly divided into two groups.In one group (MEG + icEEG group),including 43 patients,the MEG results were provided to affect the initial intracranial electrodes placement decision which was based on case -history,semilogy,EEG,MRI.By contrast,for the other group(icEEG group),including 40 patients,the MEG localization results were not provided.All patients underwent epileptogenic foci surgical resection.The follow-up was performed at least 12 months after the operation.The surgical outcome was evaluated by Engel curative effect grading.Engel Ⅰ,Ⅱ,Ⅲ was defined as effectiv whereas Engel Ⅳ was recognized as invalid.Results According to the surgical outcome of icEEG group,23 patients (54％) obtained good postsurgical seizure outcome.While in MEG + icEEG group,the rate was 78％ (31/40).There was statistically significant difference between the two groups(x2 =5.256,P =0.022).Conclusions MEG spike localization could affect icEEG by indicating the electrodes placement,increasing the chance that the seizure onset zone is sampled and improving diagnostic yield of icEEG when patients undergo icEEG for presurgical epilepsy evaluations,finally promote the effectiveness of the surgical resection. Key words: Magnetoencephalography; Intracranial electroencephalography; Epilepsy; Surgery

Improvements in Quality of Life and Mood with Treatment of Medically Intractable Partial Epilepsy with a Responsive Neurostimulator (P01.046)

Improvements in Quality of Life and Mood with Treatment of Medically Intractable Partial Epilepsy with a Responsive Neurostimulator (P01.046)

Vagus nerve stimulation after lead revision

Vagus nerve stimulation (VNS) has demonstrated benefit in patients with medically intractable partial epilepsy. As in other therapies with mechanical devices, hardware failure occurs, most notably within the VNS lead, requiring replacement. However, the spiral-designed lead electrodes wrapped around the vagus nerve are often encased in dense scar tissue hampering dissection and removal. The objective in this study was to characterize VNS lead failure and lead revision surgery and to examine VNS efficacy after placement of a new electrode on the previously used segment of vagus nerve. The authors reviewed all VNS lead revisions performed between October 2001 and August 2011 at the University of Iowa Hospitals and Clinics. Twenty-four patients underwent 25 lead revisions. In all cases, the helical electrodes were removed, and a new lead was placed on the previously used segment of vagus nerve. All inpatient and outpatient records of the 25 lead revisions were retrospectively reviewed. Four cases were second lead revisions, and 21 cases were first lead revisions. The average time to any revision was 5 years (range 1.8-11.1 years), with essentially no difference between a first and second lead revision. The most common reason for a revision was intrinsic lead failure resulting in high impedance (64%), and the most common symptom was increased seizure frequency (72%). The average duration of surgery for the initial implantation in the 15 patients whose VNS system was initially implanted at the authors' institution was much shorter (94 minutes) than the average duration of lead revision surgery (173 minutes). However, there was a significant trend toward shorter surgical times as more revision surgeries were performed. Sixteen of the 25 cases of lead revision were followed up for more than 3 months. In 15 of these 16 cases, the revision was as effective as the previous VNS lead. In most of these cases, both the severity and frequency of seizures were decreased to levels similar to those following the previous implantation procedure. Only 1 complication occurred, and there were no postoperative infections. Lead revision surgery involving the placement of a new electrode at the previously used segment of vagus nerve is effective at decreasing the seizure burden to an extent similar to that obtained following the initial VNS implantation. Even with multiple lead revisions, patients can obtain VNS efficacy similar to that following the initial lead implantation. There is a learning curve with revision surgery, and overall the duration of surgery is longer than for the initial implantation. Note, however, that complications and infection are rare.

Neuropsychological Outcome After Temporal Lobe Epilepsy Surgery in Patients With Postoperative Seizures following Unsuccessful Surgical Therapy

Background: About 20-30% of patients with intractable partial epilepsy have less than favorable outcome after temporal lobectomy. This study explored the neuropsychological outcome of such surgery in this group of patients. Methods: The Medical records of patients with intractable temporal lobe epilepsy who underwent temporal lobectomy were reviewed. All patients had detailed phase I presurgical evaluation and subsequently had surgery. Detailed neuropsychology assessment was carried out in all patients pre-operatively as well as between 3 and 12 months following surgery, 13 patients with Engel class 3 outcome were included in the study. Results: There was no significant difference in the pre and post surgical IQ, verbal and visual-spatial memory performance. However, 76.9% of the patients improved in attention/executive function, 62.6% improved in language function and 88.6% improved in psycho-emotional function. Conclusions: Despite suboptimal epilepsy surgery outcome, this study demonstrates that attention /executive function, language, and psycho-emotional function improved substantially in this sample of patients. J Neurol Res. 2012;2(5):198-203 doi: https://doi.org/10.4021/jnr149w

Responsive cortical stimulation for the treatment of medically intractable partial epilepsy

Responsive cortical stimulation for the treatment of medically intractable partial epilepsy

Ictal MEG onset source localization compared to intracranial EEG and outcome: Improved epilepsy presurgical evaluation in pediatrics

Magnetoencephalography (MEG) has been shown a useful diagnostic tool for presurgical evaluation of pediatric medically intractable partial epilepsy as MEG source localization has been shown to improve the likelihood of seizure onset zone (SOZ) sampling during subsequent evaluation with intracranial EEG (ICEEG). We investigated whether ictal MEG onset source localization further improves results of interictal MEG in defining the SOZ. We identified 20 pediatric patients with one habitual seizure during MEG recordings between October 2007 and April 2011. MEG was recorded with sampling rates of 600Hz and 4000Hz for 10 and 2min respectively. Continuous head localization (CHL) was applied. Source localization analyses were applied using multiple algorithms, both at the beginning of ictal onset and for interictal MEG discharges. Ictal MEG onsets were identified by visual inspection and power spectrum using short-time Fourier transform (STFT). Source localizations were compared with ICEEG, surgical procedure and outcome. Eight patients met all inclusion criteria. Five of the 8 patients (63%) had concordant ictal MEG onset source localization and interictal MEG discharge source localizations in the same lobe, but the source of ictal MEG onset was closer to the SOZ defined by ICEEG. Although the capture of seizures during MEG recording is challenging, the source localization for ictal MEG onset proved to be a useful tool for presurgical evaluation in our pediatric population with medically intractable epilepsy.

Seizure source imaging by means of FINE spatio-temporal dipole localization and directed transfer function in partial epilepsy patients

ObjectiveTo investigate the usage of a high-density EEG recording system and source imaging technique for localizing seizure activity in patients with medically intractable partial epilepsy. MethodsHigh-density, 76-channel scalp EEG signals were recorded in 10 patients with partial epilepsy. The patients underwent routine clinical pre-surgical evaluation and all had resective surgery with seizure free outcome. After applying a FINE (first principle vectors) spatio–temporal source localization and DTF (directed transfer function) connectivity analysis approach, ictal sources were imaged. Effects of number of scalp EEG electrodes on the seizure localization were also assessed using 76, 64, 48, 32, and 21 electrodes, respectively. ResultsSurgical resections were used to assess the source imaging results. Results from the 76-channel EEG in the 10 patients showed high correlation with the surgically resected brain regions. The localization of seizure onset zone from 76-channel EEG showed improved source detection accuracy compared to other EEG configurations with fewer electrodes. ConclusionsFINE together with DTF was able to localize seizure onset zones of partial epilepsy patients. High-density EEG recording can help achieve improved seizure source imaging. SignificanceThe present results suggest the promise of high-density EEG and electrical source imaging for noninvasively localizing seizure onset zones.

Vagus Nerve Stimulation for Epilepsy: The Notre-Dame Hospital Experience

Retrospective study assessing the efficacy and tolerability of vagus nerve stimulation (VNS) for the treatment of refractory epilepsy at Notre-Dame Hospital. Chart review of all adult epileptic patients treated by VNS with ≥ 1 year follow-up. Responders were defined as patients with ≥ 50% reduction of baseline seizure frequency. Thirty-four patients (14M; mean age = 29.9 yrs) received a VNS. Sub-pectoralis implantation (n = 25) was more frequent than subcutaneous (n = 9). Most patients suffered from intractable partial epilepsy. After 6 months, 12 months, 24 months, and 36 months, 14/34 patients (41%), 16/34 patients (47%), 17/30 patients (57%) and 12/20 patients (60%) respectively were responders. Two patients (6%) became seizure-free. Complications related to implantation were minor: eight cases of limited cervical hypoesthesia, two minor scar infections and one Horner syndrome. Adverse events (voice hoarseness, throat paresthesia, coughing) related to stimulation were generally mild and tended to wane over time. However, a reduction in seizure frequency did not translate into a reduction in medication, as only 9% of responders had less antiepileptic medication at last follow-up compared to baseline. VNS as practiced at Notre-Dame hospital is an efficacious and safe treatment for refractory epilepsy. Quotas allotted to epilepsy centers in the province of Quebec should be lifted or increased to allow more patients to benefit from this therapeutic device.

Responsive neurostimulation for the treatment of seizures that do not respond to medication

In the last 18 years, 12 new antiseizure medications have been discovered. Although there are more medications, there have been no medicines that are clearly better than the older ones. To be clear, the newer medicines do not seem to be any more effective at stopping seizures than the older ones. Studies have shown that about one-third of people with epilepsy have seizures that do not respond to antiseizure medication. A doctor will call the person's seizures refractory if they have tried 2 or more antiseizure medications, and their seizures have not stopped. Although the newer medicines do not seem to be more effective than the older ones, generally speaking, they seem to cause fewer side effects. Despite this, many patients have difficulty tolerating the high doses that are needed to control their seizures. Because of this, there has been increasing interest in devices that can help to control seizures. One device, the vagus nerve stimulator (VNS), is already available. It was approved for use by the US Food and Drug Administration (FDA) in 1997 for the treatment of refractory epilepsy. Other devices are being studied now, including the responsive cortical stimulator (also known as the responsive neurostimulator or RNS), as discussed in this Patient Page. In their study, “Responsive cortical stimulation for the treatment of medically intractable partial epilepsy,” Dr. Morrell et al.1 studied a new kind of brain stimulator for the treatment of refractory seizures. Their idea was simple: to study a device that would respond to a person's seizures. In other words, is it possible to develop a device that works only when needed? If so, is the implantable neurostimulator both safe and effective? In order to do this, the study was carried out at 32 epilepsy centers around the country. It took 3 years to …

Responsive Cortical Stimulation Found Effective for Intractable Partial Epilepsy

Responsive Cortical Stimulation Found Effective for Intractable Partial Epilepsy

Responsive cortical stimulation for the treatment of medically intractable partial epilepsy

This multicenter, double-blind, randomized controlled trial assessed the safety and effectiveness of responsive cortical stimulation as an adjunctive therapy for partial onset seizures in adults with medically refractory epilepsy. A total of 191 adults with medically intractable partial epilepsy were implanted with a responsive neurostimulator connected to depth or subdural leads placed at 1 or 2 predetermined seizure foci. The neurostimulator was programmed to detect abnormal electrocorticographic activity. One month after implantation, subjects were randomized 1:1 to receive stimulation in response to detections (treatment) or to receive no stimulation (sham). Efficacy and safety were assessed over a 12-week blinded period and a subsequent 84-week open-label period during which all subjects received responsive stimulation. Seizures were significantly reduced in the treatment (-37.9%, n = 97) compared to the sham group (-17.3%, n = 94; p = 0.012) during the blinded period and there was no difference between the treatment and sham groups in adverse events. During the open-label period, the seizure reduction was sustained in the treatment group and seizures were significantly reduced in the sham group when stimulation began. There were significant improvements in overall quality of life (p < 0.02) and no deterioration in mood or neuropsychological function. Responsive cortical stimulation reduces the frequency of disabling partial seizures, is associated with improvements in quality of life, and is well-tolerated with no mood or cognitive effects. Responsive stimulation may provide another adjunctive treatment option for adults with medically intractable partial seizures. This study provides Class I evidence that responsive cortical stimulation is effective in significantly reducing seizure frequency for 12 weeks in adults who have failed 2 or more antiepileptic medication trials, 3 or more seizures per month, and 1 or 2 seizure foci.

Effects of Propofol on Electrocorticography in Patients With Intractable Partial Epilepsy

Propofol's potential to trigger generalized tonic-clonic seizures and epileptic discharges is still controversial. The aim of this study was to investigate the incidence of epileptic discharges and epileptic seizures in epilepsy patients anesthetized with propofol. Thirty three patients with intractable partial epilepsy selected for video electrocorticography-monitoring were studied. Twenty-three of them had epilepsy surgery with at least one year of followup. Subdural electrodes were surgically removed under propofol anesthesia. Video electrocorticography recordings were classified into two phases (Phase-A, ≥2 min without propofol, followed by Phase-P, starting 20 s after propofol injection) and visually analyzed concerning the occurrence of spikes, and spike-burst-suppression-patterns. No seizures were detected. Spikes were recorded in Phase-P, but without a significant change in frequency compared to Phase-A. Spike-burst-suppression-patterns occurred in 8 of the 33 patients (24.2%). Five of those patients (62.5%) had epilepsy surgery, 3 (60%) became seizure-free. Our results do not contraindicate the use of propofol in patients with partial epilepsy. While spike-burst-suppression-patterns were recorded under propofol, the small number of surgically treated patients limits conclusions concerning their predictive value for improved epilepsy surgery outcome.

PRE-SURGICAL EVALUATION OF INTRACTABLE EPILEPSY IN CHILDREN

Corresponding Author: A. Gorji MD Institute of Physiology I, Munster Universitat, Robert-Koch-Strasse 27a D-48149 Munster, Germany Tel: +49-251-8355564 Fax: +49-251-8355551 E-mail: gorjial@uni-muenster.de Abstract Objective This review summarizes some patterns of pre-surgical evaluation of epilepsy in children with medically refractory seizures. Epilepsy surgery is a valuable therapeutic option for many children with intractable epilepsy. The most effective treatment for intractable partial epilepsy is a focal cortical resection with excision of the area of ictal onset and initial seizure propagation (the epileptogenic zone). EEG monitoring continues to prove indispensable in pre-surgical planning of refractory epileptic patients by defining the epileptogenic zone. Technological progresses in both structural and functional neuroimaging techniques have led many medical centers to consider surgical treatment of epilepsy. In children undergoing pre-surgical evaluation, the goals of neuroimaging studies include the identification of structural abnormalities in the brain, eloquent regions of the brain including language, memory, and sensorimotor functions, and the relation of these regions to the potential epileptogenic region. Neuropsychological testing plays a crucial role in assessing the potential impact of surgery on cognitive function of the patients and helps in lateralizing the cerebral hemisphere dominant for verbal and nonverbal function in older children. The Wada test is an invasive procedure to determine language dominance and can be used to assess the risk of postoperative memory deficits in children with temporal lobe epilepsy. Some children scheduled for resection still need to undergo further precise localization of the epileptogenic zone and functional mapping with invasive EEG monitoring through intracranial subdural grid and/or depth electrodes. Epilepsy surgery has the potential of changing the life quality of children by improving or eliminating seizures in carefully selected patients.

FDG-PET improves surgical outcome in negative MRI Taylor-type focal cortical dysplasias

To determine the diagnostic accuracy and prognostic value of ¹⁸FDG-PET in a recent series of patients operated for intractable partial epilepsy associated with histologically proven Taylor-type focal cortical dysplasia (TTFCD) and negative MRI. Of 23 consecutive patients (12 male, 7-38 years old) with negative 1.5-Tesla MRI, 10 exhibited subtle nonspecific abnormalities (e.g., unusual sulcus depth or gyral pattern) and the 13 others had strictly normal MRI. FDG-PET was analyzed both visually after coregistration on MRI and using SPM5 software. Metabolic data were compared with the epileptogenic zone (EZ) determined by stereo-EEG (SEEG) and surgical outcome. Visual PET analysis disclosed a focal or regional hypometabolism in 18 cases (78%) corresponding to a single gyrus (n = 9) or a larger cortical region (n = 9). PET/MRI coregistration detected a partially hypometabolic gyrus in 4 additional cases. SPM5 PET analysis (n = 18) was concordant with visual analysis in 13 cases. Location of PET abnormalities was extratemporal in all cases, involving eloquent cortex in 15 (65%). Correlations between SEEG, PET/MRI, and histologic findings (n = 20) demonstrated that single hypometabolic gyri (n = 11) corresponded to EZ and TTFCD, which was localized at the bottom of the sulcus. Larger hypometabolic areas (n = 9) also included the EZ and the dysplastic cortex but were more extensive. Following limited cortical resection (mean follow-up 4 years), seizure freedom without permanent motor deficit was obtained in 20/23 patients (87%). ¹⁸FDG-PET coregistered with MRI is highly sensitive to detect TTFCD and greatly improves diagnosis and surgical prognosis of patients with negative MRI.

Effectiveness and safety of non-intravenous high-dose phenobarbital therapy for intractable epilepsy during childhood

High-dose phenobarbital (PB) therapy is effective for refractory status epilepticus. We reviewed medical records of patients with intractable partial epilepsies on whom performed non-intravenous high-dose PB therapy. Thirteen patients received PB rectally or orally at a dosage of 20–30 mg/kg/day initially, and the PB dosage was gradually reduced to a maintenance dosage of 5–10 mg/kg/day orally. We evaluated the effectiveness and safety of this procedure after 14 days at the maintenance dosage level. Twelve patients had partial seizures and one had secondary generalized seizures. In six of 13 patients (46%), seizure frequencies decreased more than 50%, and two of 13 patients (15%) became seizure free. In five of seven patients who were treated by continuous midazolam infusion therapy, we were able to discontinue the midazolam therapy. Adverse effects were found in seven of 13 patients. We were able to continue high-dose PB therapy in six patients because their adverse effects were transient and improved after a decrease in PB concentration, but we discontinued this therapy in the patient who developed Stevens–Johnson syndrome. Respiratory depression and hypotension were not found in our study. We conclude that high-dose PB therapy is effective and may be considered as an additional treatment for intractable partial epilepsy in childhood.

Noninvasive cortical imaging of epileptiform activities from interictal spikes in pediatric patients

Improved non-invasive localization of the epileptogenic foci prior to epilepsy surgery would improve surgical outcome in patients with partial seizure disorders. A critical component for the identification of the epileptogenic brain is the analysis of electrophysiological data obtained during ictal activity from prolonged intracranial recordings. The development of a noninvasive means to identify the seizure onset zone (SOZ) would thus play an important role in treating patients with intractable epilepsy. In the present study, we have investigated non-invasive imaging of epileptiform activity in patients with medically intractable epilepsy by means of a cortical potential imaging (CPI) technique. Eight pediatric patients (1M/7F, ages 4–14years) with intractable partial epilepsy were studied. Each patient had multiple (6 to 14) interictal spikes (IIS) subjected to the CPI analysis. Realistic geometry boundary element head models were built using each individual's MRI in order to maximize the imaging precision. CPI analysis was performed on the IISs, and extrema in the estimated CPI images were compared with SOZs as determined from the ictal electrocorticogram (ECoG) recordings, as well as the resected areas in the patients and surgical outcomes. The distances between the maximum cortical activities of the IISs reflected by the estimated cortical potential distributions and the SOZs were determined to quantitatively evaluate the performance of the CPI in localizing the epileptogenic zone. Ictal ECoG recordings revealed that six patients exhibited a single epileptogenic focus while two patients had multiple foci. In each patient, the CPI results revealed an area of activity overlapping with the SOZs as identified by ictal ECoG. The distance from the extreme of the CPI images at the peak of IIS to the nearest intracranial electrode associated with the onset of the ictal activity was evaluated for each patient and the averaged distance was 4.6mm. In the group of patients studied, the CPI imaged epileptogenic foci were within the resected areas. According to the follow-up of the eight patients included, two were seizure free and six had substantial reduction in seizure frequency. These promising results demonstrate the potential for noninvasive localization of the epileptogenic focus from interictal scalp EEG recordings. Confirmation of our results may have a significant impact on the process of presurgical planning in pediatric patients with intractable epilepsy by dramatically reducing or potentially eliminating the use of intracranial recording.

Reasons for reoperation after epilepsy surgery: a review based on a complex clinical case with three operations

The results of surgical treatment of epileptic seizures have gradually improved in the past decade, approaching 60% to 90% seizure-free outcome in temporal lobe epilepsy and 45% to 66% in extratemporal lobe epilepsy. Unfortunately some patients continue with seizures after epilepsy surgery and the studies have shown that approximately the 3% to 15% of patients with a previous failed surgical procedure are reoperated. Selected patients may be candidates for further surgery, potentially leading to a significant decrease in the frequency and severity of seizures. In patients with intractable partial epilepsy there are many possible factors, alone or in combination, that could be related to the failure of resection. Some of the factors could be genetic or acquired predisposition to epileptogenicity. In this article we report a case with intractable epilepsy that required three interventions to render seizure free. We analyzed our specific case in the light of previous reports on reoperation and enumerate the potential reasons for reoperation that could apply to all patients with failure of an initial procedure.

Delayed Compressive Angiomatous Degeneration in a Case of Mesial Temporal Lobe Epilepsy Treated by Gamma Knife Radiosurgery

Mesial temporal lobe epilepsy (MTLE) is one of the most common causes of intractable partial epilepsy. The conventional treatment of patients with MTLE is surgical excision. Currently, gamma knife (GK) radiosurgery is being explored as an alternative treatment. We report the first delayed major complication related to this treatment. A 54-year-old woman with a medical history of a post-viral encephalitis in childhood was treated in April 2001 by GK radiosurgery for a medically refractory MTLE. Her right temporomesial area received a dose of 20 Gy at the 50% marginal isodose line. Unfortunately, the patient continued to experience seizures, although they were of shorter duration and occurred less frequently. She was seen in our department on November 8, 2007, for an intracranial hypertensive syndrome. The imaging work-up showed an expansive hemorrhagic lesion in the right mesiotemporal area. Despite corticosteroid treatment, the patient still complained about headaches on November 13, and surgery was scheduled for November 22. However, the patient returned to the emergency department on November 16 with a temporal herniation syndrome requiring an urgent surgical procedure. The expansive lesion was completely removed. Histologic examination revealed lesions of the gray and white matter consisting of severe gliosis, hemorrhagic foci, hyalinized vessels, and neovascularization, giving the brain parenchyma an angiomatous aspect. Although reports on GK radiosurgical treatment of MTLE are encouraging, this case stresses the risk of developing 6 years later an angiomatous degeneration of the targeted brain with life-threatening intracranial hypertension.

Quality of life after surgery for intractable partial epilepsy in children: A cohort study with controls

Investigate if quality of life (QOL) normalizes on long-term follow-up after surgery for partial epilepsy in children. This is a cohort study with controls in which a consecutive cohort of nineteen 2-14-year-old children who underwent focal resections for intractable partial seizures between 1996 and 2006, were matched with 19 non-surgery intractable partial epilepsy patients, and with 19 healthy subjects. The two epilepsy groups were matched for age, sex, socio-economic status (SES), cognitive level, seizure type, and seizure frequency. The healthy group was matched with the two epilepsy groups for age, sex, SES, and cognitive level. QOL was assessed using the QOLCE (Quality of Life in Childhood Epilepsy Questionnaire). In the surgery group (follow-up 3.84+/-2.26 years), 78.9% had Engel class-I versus 21.1% in non-surgery (p=0.01) (follow-up 3.44+/-2.95 years). Surgery patients were similar to healthy subjects in the social, emotional, cognitive, behavioral, and overall QOL (p>0.05) but had lower scores in the total QOL, physical, and health domains (p<0.05). Surgery patients scored better than non-surgery in the behavioral domain and the HASES (Hague Side Effects Scale) score (p<0.05). Non-surgery patients scored worse than healthy in total QOL, physical, behavioral, health, and overall QOL (p<0.05). IQ, HASS (Hague Seizure Severity Scale), and HASES scores were positively associated with total QOL score (p<0.05). Subgroup analysis on seizure-free surgery patients showed that they did not differ from healthy subjects in any of QOL domains (p>0.05, power>0.8). Our data indicate that epilepsy surgery for partial seizures in children is associated with better QOL as compared to children with intractable epilepsy who are not operated on, and suggest that in those who achieve seizure freedom normal QOL may at least potentially be possible.

EPILEPSY SURGERY AND ELECTRONIC DEVICES

Epilepsy is a chronic disorder characterized by recurrent and unprovoked seizures. The lifetime risk of developing epilepsy is 4%. Approximately 90% of the incident cases in adults have partial epilepsy. The initial response to medication is of prognostic importance. Patients with symptomatic neurologic disease, foreign-tissue lesion, or developmental delay are less likely to be rendered seizure free. The goal of treatment is to render the individual seizure free. Many patients with partial epilepsy will not attain a seizure remission with antiepileptic drug therapy. Epilepsy surgery is an effective and safe alternative form of therapy for selected patients with intractable partial epilepsy. Electronic stimulation is being considered for patients with partial seizures who are not candidates for a focal cortical resection.