Assessment of language lateralization in epilepsy patients using the super-selective Wada test.

BACKGROUND: The classical Wada test (cWada), performed by injecting a short-acting anesthetic through the intracarotid route, helps determine language dominance. In the cWada, adverse effects are observed in 10-30% of trials, hindering accurate assessments. In this study, we assessed the effectiveness of the super-selective Wada test (ssWada), a more selective approach for anesthetic infusion into the middle cerebral artery (MCA). METHODS: We retrospectively examined the data of 17 patients with epilepsy who underwent ssWada via anesthetic injection into one M1 segment of the MCA and at least one contralateral trial. RESULTS: The ssWada identified 12 patients with left language dominance, 3 with right language dominance, and 2 with bilateral language distribution. Nine trials on the language dominant side resulted in global aphasia for patients with left- or right language dominance. Of the 13 trials conducted on the non-dominant language side, 12 revealed intact language function and one resulted in confusion. Among these, the outcomes of global aphasia or no language impairment were confirmed in the contralateral trials. Among the 22 trials of unilateral M1 injections in patients with unilateral language dominance, 21 (95.5%) showed either global aphasia or no language impairment, indicating language dominance. CONCLUSIONS: The ssWada yields clear results, with a high rate of over 90% in determining the language dominant hemisphere with few side effects.

Network analysis of the relationship between social support and quality of life in patients with epilepsy.

BACKGROUND: Identifying important types of social support for patients with epilepsy is valuable to construct an effective system for support in daily life. However, previous studies have been inconsistent in identifying the most important types of social support for better quality of life (QOL) due to the high correlations between the social support factors. The present study employed network visualization analysis to identify the relationships between QOL and types of social support. METHODS: Two hundred and eighty-three patients with epilepsy (age range: 18 to 75 years) completed questionnaires of the Medical Outcomes Study Social Support Survey (MOS-SSS) and the Quality of Life in Epilepsy Inventory-31-Problems in the epilepsy monitoring unit at Tohoku University. The MOS-SSS was established to measure the four types of social support including emotional/informational support, tangible support, affectionate support, and positive social interaction. Our network visualization analysis represented the entire structure of the interrelationships between the four functions of social support and QOL. In addition, the relative importance of each function of social support were estimated by the centrality indices using three commonly used centrality indices: strength, betweenness, and closeness. RESULTS: The visualized network showed that positive social interaction and emotional/informational support were directly associated with QOL, whereas tangible support and affectionate support were not. Positive social interaction had the highest value for all three centrality indices and affectionate support had the second highest. Therefore, positive social interaction had the strongest connection to the other functions of support. DISCUSSION: Our network analysis and centrality indices findings showed that positive social interaction is the most important within the network of four types of social support and QOL. The emotional informational function is also important for directly improving QOL but is less related to the other functions. The affectionate function might be an indicator of whether a patient has a foundational relationship that leads to other functions of support. CONCLUSION: These results showed the importance of increasing positive social interaction in the social environment of patients with epilepsy. Therefore, practitioners need to encourage patients with epilepsy to increase their positive social interactions such as doing something enjoyable with others or someone to associate for relaxation to ensure high QOL. Connections outside the epilepsy support are important, such as having fun regardless of epilepsy, rather than only providing emotional or tangible support for epilepsy.

Referral odyssey plot to visualize causes of surgical delay in mesial temporal lobe epilepsy with hippocampal sclerosis.

The "odyssey plot" was used to visualize referral delays in epilepsy surgery. Participants were 36 patients (19 males; 13-67 years, median 27 years) with mesial temporal lobe epilepsy with hippocampal sclerosis (HS) who underwent resection surgery. The "referral odyssey plot" included five clinical episodes: seizure onset (T1), first visits to a non-epileptologist (T2) and to an epileptologist (T3), first admission to our epilepsy monitoring unit (EMU) (T4), and resection surgery (T5). For each patient, we identified the first seizure type: the physician who first diagnosed focal aware seizure (FAS), focal impaired awareness seizure (FIAS), focal to bilateral tonic-clonic seizure (FBTCS), and radiologically suspected HS. Within the overall delay (T1-T5, median 18 years; interquartile range [IQR] 14), non-epileptologist's delay (T2-T3, 11.5 years; IQR 12.25) was far (p < 0.0001) longer than patient's (T1-T2, 0 year; IQR 2.25), epileptologist's (T3-T4, 1 year; IQR 4), or after-EMU delay (T4-T5, 1 year; IQR 1). FAS onset cases had significantly longer T1-T2 (N = 5, median 7 years; IQR 6) than FIAS (N = 22, 0 year; IQR 1, p < 0.005) or FBTCS onset cases (N = 9, 0 year; IQR 0, p < 0.001). FAS was correctly diagnosed first by non-epileptologists in 17.9%, by out-patient epileptologists in 35.7%, and at the EMU in 46.4%. FIAS was correctly diagnosed first by non-epileptologists in 94.4% and by out-patient epileptologists in 5.6%. Non-epileptologists diagnosed FBTCS in all cases. HS was diagnosed by non-epileptologists in 13.9%, by out-patient epileptologists in 47.2%, and at the EMU in 38.9%. Early referral to epileptologists is most critical for early surgery. Early utilization of the EMU is highly recommended because FAS is often overlooked by outpatient epileptologists. The odyssey plot will be useful to improve the healthcare system for other types of epilepsy.

Effects of pain associated with orthodontic tooth movement on tactile sensation of periodontal ligaments.

OBJECTIVES: Pain associated with orthodontic tooth movement reportedly reduces periodontal ligament tactile sensation. However, the mechanism associated with the central nervous system remains unclear. This study was conducted by measuring somatosensory evoked magnetic fields (SEFs) during mechanical stimulation of teeth as they were being moved by separator elastics. Findings clarified the effects of pain on periodontal ligament tactile sensation during orthodontic tooth movement. MATERIALS AND METHODS: Using magnetoencephalography, SEFs were measured during the application of mechanical stimuli to the mandibular right first molars of 23 right-handed healthy participants (0 h). Separator elastics were subsequently inserted into the mesial and distal interdental portions of the mandibular right first molars. The same mechanical stimuli were applied again 24 h later while the SEFs were measured (24 h). After each SEF measurements, pain was also evaluated using the Visual Analog Scale (VAS). RESULTS: The VAS values were significantly higher at 24 h than at 0 h (p < 0.05). No significant difference in the peak latencies was found between those obtained at 0 h and 24 h, but the intensities around 40.0 ms in the contralateral hemisphere were significantly lower at 24 h than at 0 h (p < 0.01). CONCLUSIONS: Pain associated with orthodontic tooth movement might suppress periodontal ligament tactile sensation in the primary somatosensory cortex. CLINICAL RELEVANCE: Pain associated with orthodontic tooth movement might affect periodontal ligament sensation, consequently causing discomfort during occlusion.

Optogenetic stimulus-triggered acquisition of seizure resistance.

Unlike an electrical circuit, the hardware of the brain is susceptible to change. Repeated electrical brain stimulation mimics epileptogenesis. After such "kindling" process, a moderate stimulus would become sufficient in triggering a severe seizure. Here, we report that optogenetic neuronal stimulation can also convert the rat brain to a hyperexcitable state. However, continued stimulation once again converted the brain to a state that was strongly resistant to seizure induction. Histochemical examinations showed that moderate astrocyte activation was coincident with resilience acquisition. Administration of an adenosine A1 receptor antagonist instantly reverted the brain back to a hyperexcitable state, suggesting that hyperexcitability was suppressed by adenosine. Furthermore, an increase in basal adenosine was confirmed using in vivo microdialysis. Daily neuron-to-astrocyte signaling likely prompted a homeostatic increase in the endogenous actions of adenosine. Our data suggest that a certain stimulation paradigm could convert the brain circuit resilient to epilepsy without exogenous drug administration.

Development and validation of the Japanese version of the Epilepsy Stigma Scale in adults with epilepsy.

BACKGROUND: Self-stigma is considered to have immensely negative influences on the living and psychological states in patients with epilepsy. Understanding the stigma experienced by patients with epilepsy is essential considering its negative impact on their treatment and quality of life (QOL). However, few sufficiently validated self-report instruments are available to evaluate self-stigma in patients with epilepsy. The Epilepsy Stigma Scale (ESS) is one of the most commonly used self-reported questionnaires available to evaluate self-stigma in patients with epilepsy. The present study translated the ESS into Japanese to validate the Japanese version of the ESS (ESS-J) in Japanese adults with epilepsy. METHODS: The study included 338 patients with epilepsy (166 men, aged 18-75 years) who underwent comprehensive assessment including long-term video-electroencephalography monitoring, neuroimaging studies, and neuropsychological and psychosocial assessments in the Tohoku University Hospital Epilepsy Monitoring Unit. This study consisted of two phases: (1) translation of the ESS into Japanese using the back-translation technique; and (2) statistical analysis of the ESS-J to evaluate the factor structure, reliability, and validity. RESULTS: The 2-factor model achieved acceptable fit to the data: χ2 = 161.27, df = 34, p < 0.01, comparative fit index = 0.929, root mean square error of approximation = 0.105, standardized root mean squared residual = 0.047, Akaike's information criterion = 203.27 and, Bayesian information criterion = 283.56. These two subscales were named enacted stigma and felt stigma based on the theoretical model of self-stigma. We found the ESS-J to have acceptable internal consistency as follows: enacted (7 items; α = 0.88) and felt stigma subscale (3 items; α = 0.82). The concurrent validity was confirmed by adequate correlation with other related instruments. Both enacted and felt stigma had positive and moderate correlations with depression as measured by the Neurological Disorders Depression Inventory for Epilepsy (r = 0.44, p < 0.01; r = 0.41, p < 0.01, respectively) and with anxiety as measured by the Generalized Anxiety Disorder -7 (r = 0.48, p < 0.01; r = 0.38, p < 0.01, respectively). CONCLUSION: The ESS-J demonstrated acceptable validity and reliability. The present study provided preliminary evidence about the psychometric properties of the ESS-J, indicating the reliable factorial structure, adequate internal consistency, and satisfactory construct and concurrent validity. Measurement of the two types of self-stigma may offer a useful tool for clinical interpretation of patients' psychological state throughout epilepsy care, and as one of the patient-reported outcomes in QOL research.

Prescription trends in anti-seizure medications for adult patients with epilepsy in Japan: A retrospective cohort study using the database of health insurance claims between 2015 and 2019.

OBJECTIVE: To investigate whether newer anti-seizure medications (ASMs) are widely prescribed for a range of adult patients in Japan, including patients with previously and newly diagnosed epilepsy, or with focal and generalized epilepsies. METHODS: A retrospective cohort study was conducted using the Japanese insurance claims database including 8.4 million people to identify adults (≥16 years of age) with epilepsy diagnosis code identified between January 2015 and December 2018. Patients were included in the prevalent population if epilepsy was already diagnosed at baseline, and in the incident population if prior baseline data for at least 12 months included no epilepsy diagnosis code or ASM prescription. Patients were followed up from the month when the initial oral ASM was prescribed for up to 4 years until the end of 2019 as long as at least one ASM was prescribed. Proportions of prescribed oral ASMs were analyzed by population with epilepsy (prevalent vs. incident) and classification (focal vs. generalized). Anti-seizure medications were classified into older vs. newer ASMs according to the date of approval before and after 1990, respectively. RESULTS: A total of 24,691 patients fulfilled the eligibility criteria for the analysis. Of these, 21,046 and 3,645 were included in the prevalent and incident populations, respectively. The proportion of older ASMs significantly decreased, whereas the proportion of newer ASMs significantly increased (p < 0.0001) during the study period. This trend was more apparent in the population with incident epilepsy than in that with prevalent epilepsy, and was also apparent in the subgroup of focal epilepsy, but not in that of generalized epilepsy. Levetiracetam was the most frequently prescribed of the newer ASMs. CONCLUSION: Newer ASMs became more widely prescribed throughout the study period in populations with both prevalent and incident epilepsies, as well as the subpopulation with focal epilepsy. The advantages of newer ASMs such as better safety profiles may have led to the increasing proportions of prescriptions and newer ASMs may increase the treatment options for patients.

Acceptance of disability predicts quality of life in patients with epilepsy.

BACKGROUND: Acceptance of disability (AOD) is a key concept in rehabilitation psychology that enhances psychosocial adjustment of individuals with disability. However, the impact of AOD on well-being has never been examined for patients with epilepsy. The present study investigated whether AOD affects quality of life (QOL) in patients with epilepsy in the presence of other multiple aspects of epilepsy based on the biopsychosocial model. METHODS: We retrospectively reviewed 151 consecutive patients with epilepsy (77 men, aged 18-74 years) who underwent comprehensive assessment including long-term video-EEG monitoring, neuroimaging studies, and neuropsychological and psychosocial assessment in our epilepsy monitoring unit. Data were obtained from medical records and self-reported questionnaires. The outcome variable was QOL. Predictive variables included demographic characteristics, seizure-related variables (i.e., duration of epilepsy, seizure frequency, and number of antiepileptic drugs), psychological factors (i.e., AOD, depression, and self-stigma), and social factors (i.e., social support and education level). Acceptance of disability was measured by the Adaptation of Disability Scale-Revised (ADS-R), which we translated into Japanese with the original author's approval, and examined its internal consistency reliability. Data were analyzed using four hierarchical multiple regression analysis models. RESULTS: The mean ADS-R score was 80 (range 45-115). The predictors accounted for 42% of the variance in QOL (R2 = 0.45, ΔR2 = 0.42, F[8, 141] = 14.47, p = 0.00). Higher AOD (p < 0.01), higher social support (p < 0.01), and lower depression scores (p = 0.02) were found to contribute significantly to higher overall QOL. CONCLUSION: The present study revealed AOD as an important psychological concept, in addition to social support and depression as previously reported, to improve the QOL of patients with epilepsy. Acceptance of disability should be incorporated in the intervention to increase QOL of patients with epilepsy.

Diagnostic yield of seizure recordings and neuroimaging in patients with focal epilepsy without interictal epileptiform discharges.

OBJECTIVE: Repeated routine electroencephalography (EEG) or even long-term video-EEG monitoring (VEM) does not always record interictal epileptiform discharges (IEDs) in some patients with epilepsy. The present study investigated whether focal seizures detected by VEM and focal abnormalities on neuroimaging are useful for the diagnosis of patients with focal epilepsy without IEDs. METHODS: We retrospectively reviewed 409 consecutive patients with focal epilepsy (207 men, aged 9 to 76 years) who underwent 4- or 5-day VEM, magnetic resonance imaging (MRI), and fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) for diagnosis to identify patients without IEDs. The occurrence of focal seizures during VEM and the presence of focal abnormalities on neuroimaging were investigated in those patients. The occurrence rate of seizures during VEM was investigated in patients with daily, weekly, monthly, and yearly seizure frequency based on history-taking. RESULTS: Ninety-five (23.2%) of 409 patients with focal epilepsy did not have IEDs. Fifty-five (57.9%) of the 95 patients had focal seizures during VEM. Fifty-four patients (56.8%) showed focal abnormalities compatible with seizure semiology on neuroimaging investigations. Neither seizure recordings nor neuroimaging abnormalities were seen in 16 (16.8%) of the 95 patients. The occurrence rate of seizures during VEM depended on the seizure frequency at history-taking. However, 28 (45.9%) of 61 patients with monthly and yearly seizure frequency had focal seizures during 4- or 5-day VEM with seizure induction. CONCLUSIONS: Video-EEG monitoring can detect focal seizures in patients with focal epilepsy but no IEDs. Comprehensive assessment including VEM and neuroimaging study is important for the diagnosis.

Multiplex ligation-dependent probe amplification analysis is useful for detecting a copy number gain of the FGFR1 tyrosine kinase domain in dysembryoplastic neuroepithelial tumors.

PURPOSE: Dysembryoplastic neuroepithelial tumors (DNTs) are slow-growing glioneuronal tumors, and their genetic backgrounds are getting unveiled. Recently, fibroblast growth factor receptor 1 internal tandem duplication (FGFR1-ITD) of the tyrosine kinase domain (TKD) has been demonstrated by whole-genome sequencing. METHODS AND RESULTS: Here, we analyzed 22 DNTs using multiplex ligation-dependent probe amplification (MLPA) with formalin-fixed paraffin-embedded specimens and found a copy number gain in TKD of FGFR1 (13 cases, 59%), which suggested the presence of FGFR1-ITD. Another 5 DNTs harbored FGFR1 hot spot mutations including a double mutant case, and FGFR1 alterations were detected in 18 DNTs (82%). The BRAF V600E mutation, another important mutation in DNTs, was not observed. CONCLUSIONS: With recent findings of less frequent or absent FGFR1-ITD in pilocytic astrocytomas or rosette-forming glioneuronal tumors, the analysis of FGFR1 aberrations, especially FGFR1-ITD, was suggested to be helpful to discriminate DNTs from their histological mimics.

Atrophy of the ipsilateral mammillary body in unilateral hippocampal sclerosis shown by thin-slice-reconstructed volumetric analysis.

PURPOSE: Conventional volumetric analysis could not detect ipsilateral atrophy of the mammillary body in patients with unilateral hippocampal sclerosis. By using thin-slice-reconstructed volumetric analysis, we investigated whether the mammillary body volume is smaller on the hippocampal sclerosis side than in healthy subjects or the non-hippocampal sclerosis side. METHODS: This retrospective study included 45 patients with unilateral hippocampal sclerosis and 30 healthy subjects. Three-dimensional T1WI of 1 mm thicknesses were oversampled to a thickness of 0.2 mm (thin-slice-reconstructed images), and the mammillary bodies were segmented manually to determine mammillary body volume on each side. Mammillary body volumes on the hippocampal sclerosis side were compared with those in healthy subjects or the non-hippocampal sclerosis side. RESULTS: In patients with right hippocampal sclerosis, right mammillary body volume was both significantly smaller than that in healthy subjects (30.3 ± 10.3 vs. 43.3 ± 8.07 mm3, P < 0.001) and significantly smaller than the left mammillary body volume in each patient (30.3 ± 10.3 vs. 41.4 ± 10.1 mm3, P < 0.001). Similarly, in patients with left hippocampal sclerosis, left mammillary body volume was both significantly smaller than that in healthy subjects (37.7 ± 11.2 vs. 47.0 ± 8.65 mm3, P < 0.001) and significantly smaller than right mammillary body volume in each patient (37.7 ± 11.2 vs. 42.5 ± 7.78 mm3, P = 0.044). CONCLUSIONS: In this study, thin-slice-reconstructed volumetric analysis showed that, in patients with unilateral hippocampal sclerosis, mammillary body volume on the hippocampal sclerosis side is smaller than that in healthy subjects and the non-hippocampal sclerosis side.

Examination of the prescription of antiepileptic drugs to prenatal and postpartum women in Japan from a health administrative database.

PURPOSE: To evaluate the prevalence and patterns of prescriptions of antiepileptic drugs (AEDs) to prenatal and postpartum women in Japan using a large administrative database. METHODS: The dates of pregnancy onset and delivery were estimated using published algorithms and infant birth months. The prevalence of prescribed AEDs, the maximum dose of some AEDs, and the frequency of potential combination therapy with AEDs were evaluated for the 180 days before pregnancy onset, during pregnancy, and at 180-day postpartum. RESULTS: In total, 33 941 pregnant women were eligible for analysis. At least one AED was prescribed to 225 women (66 per 10 000 deliveries) between 180 days before pregnancy and 180-day postpartum and for 135 women (40 per 10 000 deliveries) during pregnancy. The prevalence of AED prescription declined during the first and second trimesters and increased in the third trimester and postpartum. Valproate was the most frequently prescribed drug, followed by clonazepam, lamotrigine, and carbamazepine. Nine (18.4%) of the 49 women with at least one prescription record of valproate in the first trimester were prescribed more than 600 mg/day of valproate. Concerning potential combination therapy, 40 (12 per 10 000 deliveries) concurrently received two or more AEDs between 180 days before pregnancy and 180-day postpartum, respectively, 31 (9 per 10 000 deliveries) women received these drugs during pregnancy. CONCLUSIONS: Various AEDs were prescribed to pregnant Japanese women. Women of reproductive age should select the appropriate AED before becoming pregnant, depending on the risk benefit profile.

Topiramate-induced weight loss depends on level of intellectual disability in patients with epilepsy.

OBJECTIVE: Intellectual disability (ID) is associated with weight gain caused by antiepileptic drugs such as valproic acid. The present study analyzed the relationship between ID and weight loss caused by topiramate (TPM). METHODS: Seventy-eight patients with epilepsy (35 women, aged 18 to 70years) were enrolled in this prospective study. Body weight was measured before and 1, 6, 12, and 18months after initiation of TPM treatment. Both patients and caregivers were provided information about TPM-related weight loss. The patients were divided into the group with no or mild ID (intelligence quotient >50) and the group with moderate to profound ID (intelligence quotient ≤50). RESULTS: Body weight of both groups significantly decreased until 6months but stabilized after 12months. Weight loss at 6, 12, and 18months was significantly greater in the group with no or mild ID than in the group with moderate to profound ID. Body weight change at 18months was correlated with intellectual levels (ß=0.274, p=0.011) and baseline body mass index (ß=-0.322, p=0.002) by multiple linear regression analysis. CONCLUSIONS: The present study suggests that the pattern of weight loss during TPM administration differs according to intellectual levels. Patients with ID maintained their body weight. Weight loss due to TPM might be weakened by caregiver control of food intake or inactivity.

Differences in sleep architecture between left and right temporal lobe epilepsy.

To investigate whether seizure lateralization affects sleep macrostructure in patients with left and right temporal lobe epilepsy (TLE), as rapid eye movement (REM) sleep is shorter in patients with right hemispheric cerebral infarction than with left. We retrospectively analyzed data from 16 patients with TLE (6 men and 10 women aged 34.9 ± 11.4 years) who underwent polysomnography as well as long-term video electroencephalography. Ten patients were diagnosed with left TLE and six patients with right TLE. Sleep stages and respiratory events were scored based on the American Academy of Sleep Medicine criteria. Sleep and respiratory parameters were compared between the patient groups. Percentage of REM stage sleep was significantly (p < 0.05) lower in patients with left TLE (median 8.8 %, interquartile range 5.5-13.8 %) than in patients with right TLE (median 17.0 %, interquartile range 14.1-18.3 %). The other parameters showed no significant differences. Shorter REM sleep in patients with left TLE sharply contrasts with the previous report of shorter REM sleep in patients with right cerebral infarction. Laterality of the irritative epileptic focus versus destructive lesion may have different effects on the sleep macrostructures.

The current state of epilepsy guidelines: A systematic review.

OBJECTIVE: The International League Against Epilepsy (ILAE) Epilepsy Guidelines Task Force, composed of 14 international members, was established in 2011 to identify, using systematic review methodology, international epilepsy clinical care guidelines, assess their quality, and determine gaps in areas of need of development. METHODS: A systematic review of the literature (1985-2014) was performed in six electronic databases (e.g. Medline, Embase) using a broad search strategy without initial limits to language or study design. Six gray literature databases (e.g., American Academy of Neurology [AAN], ILAE) were also searched to minimize publication bias. Two independent reviewers screened abstracts, reviewed full text articles, and performed data abstraction. Descriptive statistics and a meta-analysis were generated. RESULTS: The search identified 10,926 abstracts. Of the 410 articles selected for full text review, 63 met our eligibility criteria for a guideline. Of those included, 54 were in English and 9 were in other languages (French, Spanish, and Italian). Of all guidelines, 29% did not specify the target age groups, 27% were focused on adults, 22% included only children, and 6% specifically addressed issues related to women with epilepsy. Guidelines included in the review were most often aimed at guiding clinical practice for status epilepticus (n = 7), first seizure (n = 6), drug-resistant epilepsy (n = 5), and febrile seizures (n = 4), among others. Most of the guidelines were therapeutic (n = 35) or diagnostic (n = 16) in nature. The quality of the guidelines using a 1-7 point scale (7 = highest) varied and was moderate overall (mean = 4.99 ± 1.05 [SD]). SIGNIFICANCE: We identified substantial gaps in topics (e.g., epilepsy in the elderly) and there was considerable heterogeneity in methodologic quality. The findings should offer a valuable resource for health professionals caring for people with epilepsy, since they will help guide the prioritization, development, and dissemination of future epilepsy-related guidelines.

Interhemispheric Vertical Hemispherotomy: A Single Center Experience.

PURPOSE: Hemispheric epileptogenic lesions such as hemimegalencephaly often manifest as intractable epilepsy in early infancy. Hemispherotomy is the treatment of choice for controlling intractable hemispheric epilepsy. Less invasive procedures are desirable for surgery on infants with low body weight. This study compared our experience with interhemispheric vertical hemispherotomy (IVH) and peri-insular lateral hemispherotomy (PIH). METHODS: Thirteen consecutive patients underwent hemispherotomy for treatment of intractable epilepsy in our institution between 2001 and 2012. The etiology of epilepsy included hemimegalencephaly in 7 patients and cortical dysplasia in 3. PIH was performed on the first 5 patients and IVH on the last 8 patients. In the latter procedure, complete section of the corpus callosum was first performed via the interhemispheric approach. After removing part of the cingulate gyrus, section of the descending fibers was performed anterolaterally to the thalamus. Clinical characteristics, duration of operation and amount of blood transfusion were compared between the PIH and IVH groups. RESULTS: There was no difference in age at surgery, body weight and age of epilepsy onset between the two groups. No surgery-related death was observed. No patients required shunt operation. One patient who underwent IVH required reoperation for incomplete disconnection. The amount of intraoperative blood transfusion was smaller and the total duration of operation was shorter in the IVH group than in the PIH group. CONCLUSION: The interhemispheric approach minimizes cortical resection and may be less invasive than PIH. IVH is advantageous for treating infants with low body weight.

Somatosensory evoked spikes in normal adults detected by magnetoencephalography.

OBJECTIVE: Somatosensory evoked spikes (SESs) have been reported only in children aged under 14 years and are considered as an age-dependent phenomenon. However, we detected SESs in adult patients with epilepsy using magnetoencephalography (MEG). The present study investigated whether MEG can detect SESs in normal adults. METHODS: Spontaneous MEG was recorded during measurement of somatosensory evoked fields (SEFs) for bilateral electrical median nerve stimuli in 30 healthy adults. RESULTS: Bilateral SESs were observed in 10 adults but none in the other 20 subjects. SESs consisted of one or two peaks, and the first peak latency corresponded to that of the second peak (M2) of SEFs. The first SES peak was identical to the M2 in isofield map pattern, as well as location and orientation of the equivalent current dipole (ECD). M2 ECD strength in the 10 subjects with SESs was larger (p <0.0001) than in 20 without SESs. CONCLUSIONS: All-or-nothing detection of bilateral SESs by MEG in normal adults must depend on the signal-to-noise issue of symmetrical SEFs and background brain activity. SIGNIFICANCE: Our results further confirm the higher sensitivity of MEG compared to scalp EEG for the detection of focal cortical sources tangential to the scalp such as SESs.

Remission of startle epilepsy provoked by acoustic stimuli following complete callosotomy: A case study.

Herein, we present the case of a 21-year-old man with a history of generalized tonic seizures since the age of 4 years. These seizures occurred either spontaneously or could be provoked by auditory stimuli such as the sounds of a vacuum cleaner or an electric shaver. Despite trials with 10 different anti-seizure medications, his seizures remained refractory. Interictal electroencephalography (EEG) revealed generalized epileptiform activity, whereas ictal EEG showed a generalized attenuation pattern. Magnetic resonance imaging revealed extensive chronic infarctions, predominantly in the bilateral cerebral watershed areas. At the age of 17, the patient underwent a one-stage complete callosotomy, which only achieved remission of auditory-provoked seizures. Based on this experience and published reports, we propose that the posterior corpus callosum, particularly the isthmus and anterior splenium, may be involved in seizures caused by unexpected sound stimuli.

Complete Corpus Callosotomy Brings Worthwhile Seizure Reduction in Both Pediatric and Adult Patients.

BACKGROUND AND OBJECTIVES: The influence of the age at which complete corpus callosotomy (CC) surgery is performed on seizure outcomes remains unclear. This study aimed to evaluate the age-dependent aspects of long-term seizure outcomes after complete CC. METHODS: We reviewed 41 patients who underwent one-stage complete CC. Seizure outcomes were analyzed for age at epilepsy onset and at complete CC, focal MRI abnormality, and etiology. RESULTS: The median age was 7 months at epilepsy onset and 93 months at complete CC. The median follow-up duration was 67 months. Sixteen patients had focal MRI lesions and 4 had only general atrophy. Etiology was identified in 20 patients. For overall seizure outcomes (N = 41), complete seizure freedom was achieved in 5 patients, excellent seizure reduction (>80%) in 11, good (50%-80%) in 5, and poor (<50%) in 20. Freedom was correlated with younger age at complete CC and unknown etiology (P ≤ .05). Freedom was only achieved in patients aged younger than 7 years. Worthwhile (≥50%, freedom, excellent, and good) and not worthwhile (<50%, poor) overall seizure reduction showed no statistical difference in age at complete CC. No related factor was found for worthwhile overall seizure reduction. For drop attack outcomes (N = 31), freedom was achieved in 22 cases, excellent in 5, and poor in 4. Freedom was correlated with younger age at complete CC (P < .05) although freedom was achieved in 4 of 7 patients older than 20 years. Age at complete CC showed no statistical difference between worthwhile (≥50%) and not worthwhile (<50%) drop attack reduction. Worthwhile drop attack reduction was correlated with unknown etiology (P < .05). Complications were mild and transient. CONCLUSION: Complete CC is an excellent surgical option based on favorable seizure outcomes and acceptable complications in our present study.

"Caterpillar sign" in corpus callosum associated with curvilinear pericallosal lipoma in MRI: A case report.

Lipoma of the corpus callosum, also known as pericallosal lipoma, is a rare congenital brain abnormality associated with corpus callosum dysgenesis or agenesis. Two morphological types are described: tubulonodular and curvilinear, with the latter being mostly asymptomatic. We present the case of a 30-year-old woman with epilepsy, whose magnetic resonance imaging revealed a "caterpillar sign" in the corpus callosum associated with a curvilinear pericallosal lipoma. The "caterpillar sign" in the corpus callosum showed low signal intensity on magnetization prepared rapid acquisition with gradient echo, high signal on fluid-attenuated inversion recovery, and low on susceptibility-weighted imaging, possibly indicating abnormal blood vessels penetrating from the ventricle to the posterior callosal vein. We need to be conscious of this unusual finding, particularly when considering surgical intervention in the corpus callosum in cases of pericallosal lipoma, to avoid vascular complications.