Pure amnestic seizure: A clinico-intracranial EEG study.

OBJECTIVE: Enduring anterograde amnesia is caused by lesions in bilateral mesial temporal lobes. However, whether transient dysfunction of bilateral mesial temporal regions induces reversible amnesia has not been proven. We investigated this association in patients with epilepsy and analyzed the electroclinical correlation during pure amnestic seizures (PAS). PAS are defined as seizures with anterograde amnesia as the only ictal manifestation, accompanied by preserved responsiveness and other cognitive functions. METHODS: We retrospectively searched our intracranial EEG database to find PAS. Pure ictal amnesia was confirmed by immediate and comprehensive ictal examinations. RESULTS: Among 401 patients who underwent intracranial EEG recording, three patients with temporal lobe epilepsy (TLE) manifesting PAS were identified. The patients talked and behaved normally during seizure but did not remember the episodes afterwards. Ictal discharges were confined to bilateral mesial temporal regions, with no or mild involvement of surrounding structures. Spread of low-voltage fast activities to bilateral mesial temporal regions corresponded to onset of ictal anterograde amnesia. Two patients underwent unilateral mesial temporal resection and became seizure-free with improvement in cognitive functions. SIGNIFICANCE: PAS is a rare ictal semiology in TLE. Bilateral mesial temporal regions that play a critical role in memory encoding are presumably the symptomatogenic zones for PAS.

Status of epilepsy care delivery and referral in clinics, hospitals, and epilepsy centers in Japan: A nationwide survey.

OBJECTIVE: Collaboration among medical facilities is crucial to deliver comprehensive epilepsy care to a diverse and large population of people with epilepsy. We conducted a survey among medical facilities of various sizes throughout Japan to investigate the status of epilepsy care delivery, functioning, and referral. METHODS: With the cooperation of the Japan Neurological Society (1428 facilities), Japanese Neurosurgical Society (3489 specialists), and Epilepsy Care Network (948 facilities), a questionnaire was mailed to 5865 locations that provide epilepsy care in Japan. The facilities were classified into clinics (19 beds or less), small hospitals (SH, 20-199 beds), large hospitals (LH, 200 beds or more), and epilepsy centers (EC). The status of epilepsy care delivery, functioning, and referral was compared among the four groups. RESULTS: Responses were received from 1014 facilities (17.3% response rate). After excluding duplicate responses, 957 facilities were analyzed (394 clinics, 149 SH, 388 LH, 26 EC). EC responded "manageable" in more items of epilepsy care functions in general, especially those related to epilepsy surgery, compared to LH with similar facility size. However, EC responded being less manageable in psychiatric service (61.5%), dietary therapy (46.2%), rehabilitation (53.8%), and patient employment support (61.5%). The percentage of facilities that responded "always able to refer" was highest in clinics (67.6%) and the lowest in EC (40%). Referral difficulties were more commonly encountered in EC, and less common in clinics. In EC, the most common reason for inability to refer was patient or family refusal (64%). SIGNIFICANCE: We have clarified the epilepsy care delivery, functioning, and referral in facilities of various sizes in Japan. This study highlights the issues of downward referral and patient stagnation in EC, which have not received much attention. PLAIN LANGUAGE SUMMARY: A nationwide survey of healthcare facilities ranging in size from small clinics to large hospitals in Japan examined medical care delivery and patient referrals related to epilepsy. Compared to other facilities, epilepsy centers provided a variety of medical services to people with epilepsy but were inadequate in addressing psychiatric symptoms, providing dietary therapy, rehabilitation, and patient employment support. Referrals from epilepsy centers to other medical facilities were often refused by patients and their families. This results in patient crowding at epilepsy centers.

Efficacy and tolerability of lacosamide and controlled-release carbamazepine monotherapy in patients with newly diagnosed temporal lobe epilepsy: Post hoc analysis of a randomized, double-blind trial.

PURPOSE: Temporal lobe epilepsy (TLE) is often associated with drug-resistant seizures. We evaluated the efficacy and tolerability of lacosamide (LCM) versus controlled-release carbamazepine (CBZ-CR) monotherapy in adults with newly diagnosed TLE. METHODS: Exploratory post hoc analysis of patients with temporal focus of localization (indicated as the only localization focus) in a double-blind, noninferiority, phase 3 trial (SP0993; NCT01243177) in patients aged ≥ 16 years with newly diagnosed epilepsy randomized 1:1 to LCM or CBZ-CR monotherapy. RESULTS: Of 886 treated patients in this trial, temporal lobe focus of localization (TLE) was reported as the single focus for 287 (32.4%) patients (LCM 134, CBZ-CR 153). A similar proportion of patients with TLE on LCM (82  [61.2%]) and CBZ-CR (99  [64.7%]) completed the trial. Kaplan-Meier estimates for 6- and 12-month seizure freedom at the last evaluated dose level (stratified by number of seizures in the 3 months before screening  [≤2 or >2 seizures]) were similar with LCM and CBZ-CR (6 months overall: 88.7% and 89.7%; 12 months overall: 78.3% and 81.7%). Treatment-emergent adverse events (TEAEs) were reported by fewer patients on LCM (73.9%) than CBZ-CR (81.0%). Drug-related TEAEs (assessed by the investigator) were reported in 41.8% of patients on LCM and 52.3% of patients on CBZ-CR; 11.2% of patients on LCM and 15.0% on CBZ-CR discontinued due to TEAEs. CONCLUSION: Lacosamide was efficacious and generally well tolerated as monotherapy in patients with TLE with efficacy outcomes comparable with CBZ-CR, and fewer patients on LCM reported any TEAEs, drug-related TEAEs, or discontinued due to TEAEs.

Mesial temporal lobe epilepsy with amygdalar hamartoma-like lesion: Is it a distinct syndrome?

INTRODUCTION: We examined the clinical, semiological, scalp electroencephalographic (EEG), and neuropsychological features of patients with amygdalar hamartoma-like lesion (AHL) without hippocampal sclerosis (HS). METHODS: This retrospective study included 9 patients with mesial temporal lobe epilepsy (MTLE) who had an amygdalar lesion on preoperative MRI; underwent mesial temporal resection; were diagnosed with amygdalar hamartoma-like lesion (AHL) without hippocampal sclerosis (HS); were followed up for at least 2 years after surgery; and had a favourable postoperative seizure outcome (Engel Class I). There were 5 women and 4 men, and age at surgery ranged from 19 to 54 (mean, 36.6) years. Clinical characteristics, auras, video-recorded seizure semiology, interictal and ictal EEG, and preoperative neuropsychological data were reviewed. Twenty patients with MTLE with HS who had favourable postoperative seizure outcomes (Engel Class I) were selected as controls. RESULTS: Age at seizure onset was significantly higher in patients with AHL without HS than in those with HS. Fear was more frequently seen in patients with AHL (44 %) than in those with HS (5 %) (P = 0.022). There were no significant differences in interictal epileptiform discharges or ictal EEG pattern. Preoperative full-scale IQ score was significantly higher in the AHL group than in the HS group (mean, 92.9 v. 74.8, P = 0.004), as was preoperative memory quotient score (mean 100.7 v. 85.1, P = 0.028). CONCLUSION: We clarified the clinical, semiological, and neuropsychological features of patients with MTLE-AHL. These findings may be useful for preoperative evaluation, especially of patients with suspected MTLE but without apparent HS on preoperative MRI.

[Diagnosis and Classification of Epilepsy: Clinical Reasoning].

Epilepsy is defined as a chronic disorder that presents with recurrent episodes of unprovoked seizures. Epileptic seizures are caused by excessive excitation of cortical neurons. The condition has various etiologies and comorbidities. Here, we introduce the definition of epilepsy and classify it based on the newly proposed ILAE (International League Against Epilepsy) classification. In addition, we explain the process of diagnosing epilepsy and delineating the epileptic focus by presenting a case description. Transient functional alterations occur in an epileptic focus only during seizures. Thus, epileptologists are required to record a detailed history and examine its semiology to determine the epileptic focus based on knowledge in neuroscience and epileptology.

Bilateral tonic-clonic seizure and focal cortical hyperexcitability in familial Creutzfeldt-Jakob disease with E200K mutation of the prion protein.

Convulsive epileptic seizures are rare in Creutzfeldt-Jakob disease (CJD), and their clinical and EEG features have not been reported in detail. We describe a case of familial CJD with an E200K mutation of the prion protein who presented with bilateral tonic-clonic seizures (BTCS) during long-term video-EEG monitoring. Semiologically, BTCS showed focal clinical signs such as head turning and eye deviation to the left. The ictal EEG started with generalized polyspikes. Interictal EEG showed generalized periodic discharges with right fronto-temporal predominance (larger amplitude and earlier onset compared with other regions). MRI showed high-intensity signals persistently in the right temporo-parietal region on diffusion-weighted images (DWI). Interictal single-photon emission computed tomography (SPECT) showed hyperperfusion in the same region. Brain pathology revealed typical spongiform changes in CJD without other pathological findings of rapidly progressive dementia. Our case demonstrates that CJD can cause BTCS with generalized EEG changes and focal semiological/imaging abnormalities, suggesting that diffuse and inhomogeneous cortical and subcortical epileptic networks may develop in familial CJD.

PRRT2 mutation in a Japanese woman: Adult-onset focal epilepsy coexisting with movement disorders and cerebellar atrophy.

Proline-rich transmembrane protein 2 (PRRT2) was confirmed as the causative gene of paroxysmal kinesigenic dyskinesia (PKD) as shown by genome-wide linkage analyses. PRRT2 mutations are also associated with benign familial infantile seizures, infantile convulsions and choreoathetosis, and childhood absence epilepsy, but few reports have investigated adult-onset epilepsy. We describe here a rare presentation of adult-onset focal epilepsy with a PRRT2 mutation in a 31-year-old woman who showed cerebellar atrophy, familial paroxysmal kinesigenic dyskinesia, and paroxysmal non-kinesigenic dystonia. Video-electroencephalography (EEG) demonstrated focal impaired awareness seizures, in which ictal EEG changes showed left temporal onset with rhythmic theta activity over the left temporal region. Magnetic resonance imaging showed mild cerebellar atrophy. The administration of lamotrigine 50 mg/day resulted in freedom from her seizures and lamotrigine 150 mg/day reduced paroxysmal non-kinesigenic dystonia. Furthermore, she had a rare frameshift mutation, c.604_607del, p.Ser202fs of which the pathogenicity has been reported in ClinVar, but it has not been reported in Japan. Mutation of the PRRT2 gene can cause adult-onset epilepsy, paroxysmal non-kinesigenic movement disorder, and cerebellar atrophy, suggesting an expanding clinical phenotypic spectrum associated with PRRT2 mutations.

Impact of COVID-19 pandemic on epilepsy care in Japan: A national-level multicenter retrospective cohort study.

OBJECTIVE: The impact of the coronavirus disease 2019 (COVID-19) pandemic on epilepsy care across Japan was investigated by conducting a multicenter retrospective cohort study. METHODS: This study included monthly data on the frequency of (1) visits by outpatients with epilepsy, (2) outpatient electroencephalography (EEG) studies, (3) telemedicine for epilepsy, (4) admissions for epilepsy, (5) EEG monitoring, and (6) epilepsy surgery in epilepsy centers and clinics across Japan between January 2019 and December 2020. We defined the primary outcome as epilepsy-center-specific monthly data divided by the 12-month average in 2019 for each facility. We determined whether the COVID-19 pandemic-related factors (such as year [2019 or 2020], COVID-19 cases in each prefecture in the previous month, and the state of emergency) were independently associated with these outcomes. RESULTS: In 2020, the frequency of outpatient EEG studies (-10.7%, p<0.001) and cases with telemedicine (+2,608%, p=0.031) were affected. The number of COVID-19 cases was an independent associated factor for epilepsy admission (-3.75*10-3 % per case, p<0.001) and EEG monitoring (-3.81*10-3 % per case, p = 0.004). Further, the state of emergency was an independent factor associated with outpatient with epilepsy (-11.9%, p<0.001), outpatient EEG (-32.3%, p<0.001), telemedicine for epilepsy (+12,915%, p<0.001), epilepsy admissions (-35.3%; p<0.001), EEG monitoring (-24.7%: p<0.001), and epilepsy surgery (-50.3%, p<0.001). SIGNIFICANCE: We demonstrated the significant impact that the COVID-19 pandemic had on epilepsy care. These results support those of previous studies and clarify the effect size of each pandemic-related factor on epilepsy care.

Neuropsychological outcomes after frontal lobectomy to treat intractable epilepsy.

OBJECTIVE: Frontal lobectomy is often used as a surgical treatment for frontal lobe epilepsy, especially when a large epileptogenic zone in the frontal lobe is inferred from preoperative evaluation. The frontal lobe is important for cognitive functions such as executive functions and verbal fluency, but the neuropsychological outcome after a frontal or prefrontal lobectomy that includes both the dorsolateral prefrontal cortex and ventral prefrontal cortex has not been studied thoroughly. In the present study, we evaluated neuropsychological outcomes after patients with frontal lobe epilepsy received a frontal or prefrontal lobectomy. METHODS: We retrospectively reviewed the data of patients with frontal lobe epilepsy who underwent a frontal or prefrontal lobectomy that includes both the dorsolateral prefrontal cortex and ventral prefrontal cortex at 16 years or older from October 2004 to December 2014, with a minimum postoperative follow-up of 24 months. We analyzed and compared neuropsychological outcomes, including executive functions, verbal fluency, intelligence, and memory, before and after the operation. RESULTS: Eighteen patients were 16 years or older and underwent pre- and postoperative (2 years after the operation) neuropsychological evaluations. Patients showed significant deterioration only on the Benton Visual Retention Test. Performance on tests of frontal lobe functions, such as executive function and verbal fluency, showed no significant deterioration. CONCLUSIONS: Overall cognitive performance, including functions widely thought to depend on the frontal lobe, is stable after a frontal or prefrontal lobectomy to treat frontal lobe epilepsy.

Semiological differences of focal onset bilateral motor (convulsive) seizure between mesial temporal lobe epilepsy and neocortical epilepsy.

OBJECTIVE: We investigated the semiology of focal onset bilateral motor (convulsive) seizure (FBMS) in patients with intractable focal epilepsy who underwent epilepsy surgery to understand its value in localizing the origin of the seizure. METHODS: The study included 20 patients who underwent resective surgery after intracranial video-EEG monitoring (iEEG) with a favorable seizure outcome (Engel class I), and had at least one FBMS during iEEG. The diagnosis was mesial temporal lobe epilepsy (MTLE) for 7 patients and neocortical epilepsy (NE) for 13 patients (lateral temporal lobe, 3; posterior cortex, 6; frontal lobe, 3; perirolandic, 1). Videotaped FBMSs were carefully analyzed. RESULTS: A generalized tonic phase appeared in all 7 patients with MTLE, but was absent in 6 of the 13 patients with NE (P = .044). Tonic cry was more frequently observed in MTLE than in NE (P = .012). Facial tonicity preceding limb tonicity was more frequently seen in patients with MTLE (P = .001). CONCLUSION: Notably, patients with MTLE and those with NE showed semiological differences during bilateralization. FBMS includes not only focal to bilateral tonic-clonic seizure but also focal to bilateral clonic seizure.

[GABAB receptor autoimmune encephalitis presenting as transient epileptic amnesia].

This case was a 50-year-old healthy woman. After repeated transient amnesia, she developed tonic-clonic seizures and was admitted to our hospital. The brain MRI showed FLAIR hyperintensities in the left temporal lobe and EEG showed an epileptic discharge starting from the left temporal region. Based on these findings, we diagnosed temporal lobe epilepsy associated with acute limbic encephalitis. While she experienced recurrent transient amnesia, her cognitive functions were preserved except for her memory. These symptoms and EEG findings were consistent with transient epileptic amnesia (TEA). Acute limbic encephalitis that occurred in a healthy middle-aged woman may be antibody-mediated encephalitis, requiring immediate immunotherapies. In this case, GABAB receptor antibodies in cerebrospinal fluid were found positive. This is the first report showing that TEA was caused by GABAB receptor autoimmune encephalitis.

Retained absolute pitch after selective amygdalohippocampectomy.

This study assessed the pre-operative chronic condition and effect of epilepsy surgery in a 21-year-old Japanese woman with drug-resistant right temporal lobe epilepsy (TLE). For this patient, it was crucially important to preserve language and her music capabilities, including absolute pitch (AP), which is found in the general population at less than 0.1%. The patient became seizure free, and her AP capability was preserved after selective amygdalohippocampectomy in the non-dominant right hemisphere. Most of the neuropsychological test (WAIS-III and WMS-R) scores remained in the normal range, except for low scores in verbal memory and markedly improved attention/concentration index. The patient's pre- and postoperative brain function related to language and music capabilities were investigated using functional magnetic resonance imaging (fMRI) based on two language tasks and a music task (listening to melodies). While task performance was similar in pre- and postoperative examinations, her brain activation patterns markedly differed. The most striking difference was during the music task: areas with significant activation existed in the bilateral frontal and temporal lobes before surgery, whereas postoperative activation was confined to a very limited region in the left angular gyrus. The authors speculate that the surgery triggered some change in functional organization in the brain, which contributed to preserving her capabilities.

Therapeutic Monitoring of Lacosamide in Japanese Patients With Epilepsy: Clinical Response, Tolerability, and Optimal Therapeutic Range.

BACKGROUND: Lacosamide is a novel anticonvulsant that acts by enhancing sodium channel slow inactivation. The aims of this study were to evaluate the influence of concomitant antiepileptic drugs (AEDs) on serum lacosamide concentration and explore the relationship between lacosamide serum concentration and both clinical response and adverse effects. METHODS: The authors analyzed 649 serum samples from 426 Japanese patients with epilepsy. The concentration-to-dose (CD) ratio of lacosamide was compared among patients on various AED regimens. Clinical information about seizure frequency and adverse events was obtained from clinical records. RESULTS: In patients who did not receive enzyme-inducing AEDs, the CD ratio (mean ± SD) of lacosamide was 1.84 ± 0.68. By contrast, the CD ratio in patients who received phenytoin, carbamazepine, and phenobarbital was 1.42 ± 0.66 (22.8% lower), 1.46 ± 0.40 (20.7% lower), and 1.36 ± 0.38 (26.1% lower), respectively. Seventy-four patients (17.3%) achieved >50% seizure reduction. The median lacosamide concentration in patients who received and did not receive a sodium channel blocker was 6.6 mcg/mL (26.4 µmol/L) and 8.4 mcg/mL (33.6 µmol/L), respectively. Adverse events, including dizziness, somnolence, diplopia, and anorexia, were reported by 70 patients (16.4%). The incidence rate in patients treated with sodium channel blockers was significantly higher than that in patients not treated with these drugs (21.1% vs. 10.3%; P < 0.005), and the median lacosamide concentration in these patient groups was 5.1 (20.4 µmol/L) and 7.5 mcg/mL (30 µmol/L), respectively. CONCLUSIONS: Therapeutic drug monitoring of lacosamide is clinically useful because it allows physicians to estimate the extent of drug interactions and adjust the dose in individual AED regimens.

Changes in serum perampanel concentration profile after discontinuation of carbamazepine.

To evaluate changes in the pharmacokinetics of perampanel after discontinuation of carbamazepine. We enrolled 13 patients receiving perampanel who discontinued carbamazepine therapy between June 2016 and December 2018. Data on serum concentrations were obtained from the therapeutic drug monitoring database of the National Epilepsy Center (Shizuoka, Japan). To compare the pharmacokinetics of perampanel before and after discontinuation of carbamazepine, we determined the concentration/dose (CD) ratio of perampanel (serum level [ng/mL] divided by the dose [mg/kg]). The follow-up period was set to eight weeks following the discontinuation of carbamazepine therapy. The mean baseline CD ratio of perampanel was 1,247 ng/mL/mg/kg which increased markedly over time after discontinuation of carbamazepine, with a mean CD ratio at Weeks 1-2, Weeks 3-4, and Weeks 5-8 of 2,683, 3,914, and 4,220, respectively. At eight weeks, the mean CD ratio of perampanel had increased by 276%. Eleven patients developed adverse events, including dizziness, somnolence, irritability, and ataxia. Five of these 11 patients required perampanel dose reduction within eight weeks after discontinuation of carbamazepine. Two patients achieved seizure-free status at Weeks 5-8. The serum perampanel concentration began to increase from one week after discontinuation of carbamazepine, and continued to rise for eight weeks. Based on these findings, we recommend frequent monitoring of serum perampanel concentration for at least eight weeks after stopping carbamazepine therapy. Monitoring is required as a guide for dose adjustment in order to achieve a safe and effective therapeutic dose of perampanel.

Nurse teachers' knowledge about epilepsy and communication issues between schools and medical institutions: A nationwide questionnaire survey in Japan.

OBJECTIVE: The importance of school teachers' knowledge of and attitudes toward epilepsy and the communication between educational and medical systems is widely appreciated, but exploration of these factors in Japan has been extremely limited. In order to identify issues in support systems for students with epilepsy and bridge the gaps in communication between schools and medical institutions in Japan, we performed a nationwide questionnaire survey of nurse teachers (nurses in charge of health education/care at schools). METHODS: We mailed a questionnaire to 900 nurse teachers all over Japan. It included six items on general epilepsy knowledge and 15 items on information about each student with epilepsy in their schools. We used a modified grounded theory approach (M-GTA) to analyze open-ended questions. RESULTS: We received responses from 640 (71.1%) nurse teachers. In their schools, there were 237 253 students, of whom 1565 had epilepsy. Most nurse teachers (84.7%) understood that epilepsy is a neurological disease. When performing first aid for a seizure, they would observe the seizure calmly (85.9%) and/or secure the airway (75.3%). There were 1398 responses about individual students with epilepsy (89.3%). Nurse teachers knew the seizure type in 70.0% of these students, seizure frequency in 76.8%, triggers in 38.9%, and appropriate first aid for 79.0%. Some nurse teachers (30.2%) obtained information on students with epilepsy from medical institutions. They knew more about their students' seizures than those without medical information. Existing forms for communicating information on students with epilepsy between schools and physicians were not actively utilized. Responses to open questions converged on safety at school. SIGNIFICANCE: Japanese nurse teachers understand epilepsy relatively well, but do not fully grasp the condition of each student with epilepsy. Better information flow from medical institutions is needed. Active communication is necessary to support the safety of students with epilepsy at school.

Seizures, accidental injuries at work, and reasons for resignation in people with epilepsy.

OBJECTIVE: Few studies have examined seizures, accidental injuries at work, and reasons for resignation in people with epilepsy (PWE). We performed a questionnaire survey of PWE to identify the risk of injury at work, its relationship to different seizure characteristics, and reasons for resignation. METHODS: We distributed a questionnaire survey in the outpatient clinic of a single epilepsy center. Medical information was obtained retrospectively from medical records. RESULTS: Of 200 patients who received the questionnaire, 172 responded. Two-fifths of PWE had experienced seizures at work, but the risk of accidental injuries due to epileptic seizures was only 0.01 person/year (1.0%) and 0.018 injuries/year, whereas the risk of accidental injuries not related to seizures was 0.039 person/year (3.9%) and 0.083 injuries/year. All accidental injuries due to seizures at work were caused by seizures characterized by a fall and inappropriate behavior with impaired awareness. Most accidental injuries due to seizures at work were caused by seizures that occurred at least once a year. The types of injuries reported were bruising, abrasion, laceration, fracture, burn, and submersion injuries. A quarter of PWE had left previous jobs because of epilepsy, of these, about four-fifths reported that seizures at the workplace had interfered with their own or others' tasks. SIGNIFICANCE: The risk of seizure-related injury is not high compared to the risk of injury not related to seizures, and most injuries due to seizures are not severe. The features of seizures with a fall, impaired awareness, and inappropriate behavior, as well as seizure frequency, should be considered when evaluating the risks associated with seizures in the workplace. Most PWE who had left their previous job because of epilepsy had experienced seizures at the workplace interfering with their own or others' tasks.

Alice in wonderland syndrome in an elderly patient with focal onset epilepsy.

Alice in wonderland syndrome (AIWS) is a rare perceptual disorder characterized by subjective distortions of visual and somatosensory perception. Symptoms of AIWS are attributable to functional and structural changes of the visual and somatosensory perceptual system; however, few reports have investigated the pathophysiology of AIWS with regard to epilepsy, especially ictal electroencephalogram (EEG) changes. Herein, we describe the case of an 82-year-old woman with focal onset epilepsy presenting with AIWS, whose seizures were documented by video-EEG monitoring. Video-EEG revealed multiple focal impaired awareness seizures, and ictal EEG changes arose from the right occipital region with small periodic positive discharges with evolution towards the right centro-parietal regions. Our case highlights not only a relationship between epileptic seizures and AIWS but also provides pathological insight into AIWS.

Clinical, semiological, electroencephalographic, and neuropsychological features of "pure" neocortical temporal lobe epilepsy.

We examined the clinical, semiological, scalp EEG, and neuropsychological features of patients with "pure" neocortical temporal lobe epilepsy (NTLE) who were successfully treated by neocortical temporal resection sparing the mesial temporal structures. This retrospective study included 17 patients with lesional NTLE who satisfied the following criteria: presence of a discrete structural lesion in the lateral temporal lobe on preoperative MRI; lateral temporal resection sparing the mesial temporal structures; follow-up for at least two years after surgery; and favourable postoperative seizure outcome (Engel Class I). The study included 10 females and seven males, and the age at surgery ranged from 15 to 48 years (mean: 30.7 years). Auras, video-recorded seizure semiology, interictal and ictal EEG, and pre- and post-operative neuropsychological data were reviewed. Twenty patients with mesial temporal lobe epilepsy (MTLE) with hippocampal sclerosis, who had a favourable postoperative seizure outcome (Engel Class I), were selected as a control group. Age at seizure onset was significantly greater in patients with NTLE than in controls. A history of febrile convulsion was significantly less frequent in NTLE patients. Epigastric ascending sensation (6% versus 40%; p=0.017), oral automatisms (29% versus 80%; p=0.003), gestural automatisms (47% versus 80%; p=0.047), and dystonic posturing (0% versus 40%; p=0.003) were significantly less frequent in NTLE than controls. Ictal unitemporal rhythmic theta activity was also significantly less frequent in NTLE than controls (35.3% versus 75%; p=0.015). Preoperative IQ score (range: 68 to 114; mean: 88.9) and preoperative memory quotient score (range: 56-122; mean: 98.1) were significantly higher in NTLE (p=0.003 and p=0.048, respectively). There were notable differences in clinical, semiological, EEG, and neuropsychological features between "pure" NTLE and MTLE. These findings may be useful to identify the epileptogenic zone.