Seizure focus in the frontal interhemispheric fissure leads to ipsilateral isolated eye deviation.

OBJECTIVE: Few studies have examined the localization of seizures presenting with ictal eye deviation (ED) in the absence of other motor symptoms. We aimed to investigate differences in the localization of the ictal onset zone (IOZ) between patients with isolated ED and those with ED plus head turning (HT) during focal seizures. METHODS: We reviewed intracranial video-EEG data for 931 seizures in 80 patients with focal onset epilepsy in whom the IOZ could be confirmed. The 233 seizures in 49 patients with ED were classified into two semiological groups based on initial ED and the presence/absence of HT: (1) isolated ED (i.e., ED without HT), and (2) ED + HT (i.e., ED with HT). We analyzed the localization and lateralization of IOZs in each semiological group. We performed multivariate logistic regression analysis using a mixed-effects to determine the associations between IOZs and isolated ED/ED + HT. RESULTS: A total of 183 IOZs in 24 patients were included in the isolated ED group, while a total of 143 IOZs in 31 patients were included in the ED + HT group. Sixty-eight IOZs of eight patients in the isolated ED group were located in the ipsilateral frontal interhemispheric fissure (F-IHF). Only ipsilateral F-IHF was significantly associated with isolated ED (odds ratio [OR], 2.43; 95% confidence interval [CI], 0.37-4.49; P = 0.021). The contralateral lateral frontal cortex (latF) (P = 0.007) and ipsilateral mesial temporal region (mT) (P = 0.029) were significantly associated with ED + HT. CONCLUSION: The present study is the first to demonstrate that seizures with an F-IHF focus tend to present with initial ipsilateral isolated ED. This finding may aid in identifying the seizure focus in patients with isolated ED prior to resection.

Activities of daily living are associated with outcomes of epilepsy treatment in elderly patients.

AIM: Controlling epileptic seizures in elderly populations is widely considered to be relatively easy, but we hypothesized that the lifestyles of elderly individuals may affect the outcomes of epilepsy treatment. The purpose of this study was to review the activities of daily living (ADL) of elderly individuals with epilepsy and compare them with the outcomes of epilepsy treatment. METHODS: Of the 177 patients ≥65 years old who were referred to our epilepsy centre, epilepsy was diagnosed in 84. ADL and treatment outcomes were then reviewed, with ADL classified into three levels: ADL I, without disability; ADL II, disabled only in some instrumental ADL; and ADL III, disabled in some basic ADL. Epilepsy syndromes and use of anti-seizure drugs were also evaluated. RESULTS: Forty-five patients (53.6%) achieved freedom from seizures, 23 (27.4%) achieved ≥80% but <100% reduction in seizures, 5 (6%) achieved ≥50% but <80% reduction in seizures, and 11 (13.1%) achieved <50% reduction in seizures. Thirty-five patients (81.4%) with ADL I achieved freedom from seizures, compared with seven patients with ADL II (28.0%) and three patients with ADL III (19.0%). A significant difference was evident among the three groups (F = 6.145, P = 0.003). CONCLUSIONS: ADL should be taken into account when an epilepsy treatment is being selected.

Potential use of prostate specific membrane antigen (PSMA) for detecting the tumor neovasculature of brain tumors by PET imaging with 89Zr-Df-IAB2M anti-PSMA minibody.

Tumor angiogenesis has attracted increasing attention because of its potential as a valuable marker in the differential diagnosis of brain tumors as well as a novel therapeutic target. Prostate-specific membrane antigen (PSMA) is expressed by the neovasculature endothelium of some tumors, with little to no expression by the tumor cells or normal vasculature endothelium. The aim of this study was to investigate the potential of PSMA for the evaluation of the tumor neovasculature of various brain tumors and the possibility of detecting PSMA expression in brain tumors using PET imaging with 89Zr-Df-IAB2M (anti-PSMA minibody). Eighty-three tissue specimens including gliomas, metastatic brain tumors, primary central nervous system lymphomas (PCNSL), or radiation necroses were analyzed by immunohistochemical staining with PSMA antibody. 89Zr-Df-IAB2M PET scans were performed in three patients with recurrent high-grade gliomas or metastatic brain tumor. PSMA was highly expressed in the vascular endothelium of high-grade glioma and metastatic brain tumor, whereas PSMA was poorly expressed in the vascular endothelium of PCNSL and radiation necrosis. PSMA expression in high-grade gliomas and a metastatic brain tumor was clearly visualized by PET imaging with 89Zr-Df-IAB2M. Furthermore, a trend toward a positive correlation between the degree of 89Zr-Df-IAB2M uptake and PSMA expression levels in tumor specimens was observed. PET imaging of PSMA using 89Zr-Df-IAB2M may have potential value in the differential diagnosis of high-grade glioma from PCNSL or radiation necrosis as well as in the prediction of treatment efficacy and assessment of treatment response to bevacizumab therapy for high-grade glioma.

Linear Discriminant Analysis for the in Silico Discovery of Mechanism-Based Reversible Covalent Inhibitors of a Serine Protease: Application of Hydration Thermodynamics Analysis and Semi-empirical Molecular Orbital Calculation.

We recently reported that the Gibbs free energy of hydrolytic water molecules (ΔGwat) in acyl-trypsin intermediates calculated by hydration thermodynamics analysis could be a useful metric for estimating the catalytic rate constants (kcat) of mechanism-based reversible covalent inhibitors. For thorough evaluation, the proposed method was tested with an increased number of covalent ligands that have no corresponding crystal structures. After modeling acyl-trypsin intermediate structures using flexible molecular superposition, ΔGwat values were calculated according to the proposed method. The orbital energies of antibonding π* molecular orbitals (MOs) of carbonyl C=O in covalently modified catalytic serine (Eorb) were also calculated by semi-empirical MO calculations. Then, linear discriminant analysis (LDA) was performed to build a model that can discriminate covalent inhibitor candidates from substrate-like ligands using ΔGwat and Eorb. The model was built using a training set (10 compounds) and then validated by a test set (4 compounds). As a result, the training set and test set ligands were perfectly discriminated by the model. Hydrolysis was slower when (1) the hydrolytic water molecule has lower ΔGwat; (2) the covalent ligand presents higher Eorb (higher reaction barrier). Results also showed that the entropic term of hydrolytic water molecule (-TΔSwat) could be used for estimating kcat and for covalent inhibitor optimization; when the rotational freedom of the hydrolytic water molecule is limited, the chance for favorable interaction with the electrophilic acyl group would also be limited. The method proposed in this study would be useful for screening and optimizing the mechanism-based reversible covalent inhibitors.

Gibbs Free Energy of Hydrolytic Water Molecule in Acyl-Enzyme Intermediates of a Serine Protease: A Potential Application for Computer-Aided Discovery of Mechanism-Based Reversible Covalent Inhibitors.

In order to predict the potencies of mechanism-based reversible covalent inhibitors, the relationships between calculated Gibbs free energy of hydrolytic water molecule in acyl-trypsin intermediates and experimentally measured catalytic rate constants (kcat) were investigated. After obtaining representative solution structures by molecular dynamics (MD) simulations, hydration thermodynamics analyses using WaterMap™ were conducted. Consequently, we found for the first time that when Gibbs free energy of the hydrolytic water molecule was lower, logarithms of kcat were also lower. The hydrolytic water molecule with favorable Gibbs free energy may hydrolyze acylated serine slowly. Gibbs free energy of hydrolytic water molecule might be a useful descriptor for computer-aided discovery of mechanism-based reversible covalent inhibitors of hydrolytic enzymes.

[Endoscopic Endonasal Transethmoidal Biopsy for IgG4-Related Intraorbital Pseudotumor:A Case Report].

BACKGROUND: We experienced a case of intraorbital pseudotumor associated with IgG4-related disease, for which we successfully performed an endoscopic endonasal transethmoidal biopsy for the intraorbital pseudotumor as well as endoscopic sinus surgery for a refractory pansinusitis at the same time. CASE REPORT: A 59-year-old man was referred to our hospital because of an intraorbital mass lesion. MRI showed 2 mass lesions:a large intraconal lesion encasing the left optic nerve on the orbital apex, and a small extraconal lesion medial to the left medial rectus muscle extending into the anterior ethmoid canal. In addition, CT showed severe pansinusitis. A blood test showed a marked elevation of IgG4. IgG4-related pseudotumor was suspected, but IgG4-related MALT lymphoma was an alternative diagnosis, and a biopsy of the mass lesion was required. We successfully performed both, an endoscopic endonasal transethmoidal biopsy for the mass lesion and endoscopic sinus surgery for the refractory pansinusitis at the same time. The pathological diagnosis was an IgG4-related pseudotumor. CONCLUSION: Endoscopic endonasal transethmoidal biopsy is an effective and minimally invasive method for making a definitive diagnosis of IgG4-related intraorbital pseudotumor. Using this method, refractory pansinusitis frequently associated with this disease can be treated. For successful treatment, interdisciplinary decision making and collaborative team surgery are crucial.

[A case of bilateral chronic subdural hematoma due to spontaneous intracranial hypotension without orthostatic headache].

We herein present a case of bilateral chronic subdural hematoma(bilateral CSDH)caused by spontaneous intracranial hypotension(SIH)without orthostatic headache. A 67-year-old male patient with mild head injury suffered from a chronic, non-postural headache. Computed tomography of the brain showed bilateral CSDH. The hematomas were surgically evacuated using a closed drainage method. His headache immediately disappeared, but it recurred after 2 weeks. We further performed hematoma irrigation;however, his neurological status deteriorated with the development of pneumocephalus. Magnetic resonance imaging with gadolinium-DTPA showed diffuse pachymeningeal enhancement. His cerebrospinal fluid pressure was 3cmH2O, and radioisotope cisternography revealed cerebrospinal fluid leakage at the level of the cervicothoracic transition. No recurrence was found after 6 weeks of horizontal bed rest. The possibility of SIH should be considered in patients with CSDH, especially bilateral CSDH, even in elderly patients with a history of mild head trauma, and absence of orthostatic headache. Closed drainage method may be preferable in cases where surgical treatment is used.

A Case of Anorexia Nervosa with Focal Cortical Dysplasia.

Anorexia nervosa (AN) is a fatal condition associated with extreme underweight and undernutrition. It is more common in young females, with a female-to-male ratio of 10 : 1. Focal cortical dysplasia (FCD) is characterized by dysplasia of the cerebral cortex and is a common cause of pharmacoresistant epilepsy. However, FCD associated with AN has never been reported. We report the first case of AN in a 12-year-old male diagnosed with FCD-type 2 on head magnetic resonance imaging (MRI). He became concerned about lower abdominal distention and began reducing his food intake. He was admitted to our hospital after weight loss of 10 kg in a 1 year. Head MRI showed a localized high-signal area from the cortex to the white matter of the fusiform gyrus near the left hippocampus, with no associated decreased blood flow or electroencephalography (EEG) abnormalities. These findings were characteristic of FCD type II. In males with AN, the search for underlying disease is particularly important. The pathophysiology of the association between AN and FCD is unclear. However, both conditions are reportedly associated with autism spectrum disorder. Further cases are needed to clarify whether FCD is associated with eating disorders.

Endovascular electroencephalography (eEEG) can detect the laterality of epileptogenic foci as accurately as subdural electrodes.

Background: Traditional brain activity monitoring via scalp electroencephalography (EEG) offers limited resolution and is susceptible to artifacts. Endovascular electroencephalography (eEEG) emerged in the 1990s. Despite early successes and potential for detecting epileptiform activity, eEEG has remained clinically unutilized. This study aimed to further test the capabilities of eEEG in detecting lateralized epileptic discharges in animal models. We hypothesized that eEEG would be able to detect lateralization. The purpose of this study was to measure epileptiform discharges with eEEG in animal models with lateralization in epileptogenicity. Materials and methods: We inserted eEEG electrodes into the transverse sinuses of three pigs, and subdural electrodes (SDs) on the surfaces of the left and right hemispheres. We induced epileptogenicity with penicillin in the left brain of pigs F00001 and F00003, and in the right brain of pig F00002. The resulting epileptiform discharges were measured by eEEG electrodes placed in the left and right transverse sinuses, and conducted comparisons with epileptiform discharges from SDs. We also had 12 neurological physicians interpret measurement results from eEEG alone and determine the side (left or right) of epileptogenicity. Results: Three pigs were evaluated for epileptiform discharge detection using eEEG: F00001 (7 months old, 14.0 kg), F00002 (8 months old, 15.6 kg), and F00003 (8 months old, 14.4 kg). The eEEG readings were compared with results from SDs, showing significant alignment across all subjects (p < 0.001). The sensitivity and positive predictive values (PPV) were as follows: F00001 had 0.93 and 0.96, F00002 had 0.99 and 1.00, and F00003 had 0.98 and 0.99. Even though one of the neurological physicians got all sides incorrect, all other assessments were correct. Upon post-experimental dissection, no abnormalities were observed in the brain tissue or in the vascular damage at the site where the eEEG was placed, based on pathological evaluation. Conclusion: With eEEG, lateralization can be determined with high sensitivity (>0.93) and PPV (>0.95) that appear equivalent to those of subdural EEG in the three pigs. This lateralization was also discernible by neurological physicians on visual inspection.

Crystal structure of 6-guanidinohexanoyl trypsin near the optimum pH reveals the acyl-enzyme intermediate to be deacylated.

The force driving the conversion from the acyl intermediate to the tetrahedral intermediate in the deacylation reaction of serine proteases remains unclear. The crystal structure of 6-guanidinohexanoyl trypsin was determined at pH 7.0, near the optimum reaction pH, at 1.94 Å resolution. In this structure, three water molecules are observed around the catalytic site. One acts as a nucleophile to attack the acyl carbonyl carbon while the other two waters fix the position of the catalytic water through a hydrogen bond. When the acyl carbonyl oxygen oscillates thermally, the water assumes an appropriate angle to catalyze the deacylation.

Endovascular Electroencephalogram Records Simultaneous Subdural Electrode-Detectable, Scalp Electrode-Undetectable Interictal Epileptiform Discharges.

INTRODUCTION: We hypothesized that an endovascular electroencephalogram (eEEG) can detect subdural electrode (SDE)-detectable, scalp EEG-undetectable epileptiform discharges. The purpose of this study is, therefore, to measure SDE-detectable, scalp EEG-undetectable epileptiform discharges by an eEEG on a pig. METHODS: A pig under general anesthesia was utilized to measure an artificially generated epileptic field by an eEEG that was able to be detected by an SDE, but not a scalp EEG as a primary outcome. We also compared the phase lag of each epileptiform discharge that was detected by the eEEG and SDE as a secondary outcome. RESULTS: The eEEG electrode detected 113 (97%) epileptiform discharges (97% sensitivity). Epileptiform discharges that were localized within the three contacts (contacts two, three and four), but not spread to other parts, were detected by the eEEG with a 92% sensitivity. The latency between peaks of the eEEG and right SDE earliest epileptiform discharge ranged from 0 to 48 ms (mean, 13.3 ms; median, 11 ms; standard deviation, 9.0 ms). CONCLUSION: In a pig, an eEEG could detect epileptiform discharges that an SDE could detect, but that a scalp EEG could not.

Levetiracetam Versus Levetiracetam Plus Sodium Channel Blockers for Postoperative Epileptic Seizure Prevention in Brain Tumor Patients.

Background Brain tumor patients tend to develop postoperative epileptic seizures, which can lead to an unfavorable outcome. Although the incidence of postoperative epileptic seizures and adverse events are improved with the advent of levetiracetam (LEV), postoperative epilepsy occurs at a frequency of 4.6% or higher. In brain tumor patients, the addition of sodium channel blockers (SCBs) to LEV significantly reduces seizures, though confirmed in a non-postoperative study. Thus, the combination of SCBs with LEV might be promising. Objective In this prospective randomized controlled trial we investigated the safety, evaluated by adverse events during one and two weeks after surgery, and the efficacy, evaluated by the incidence of early epilepsy, including non-convulsive status epilepticus (NCSE), of using LEV alone or SCBs added to LEV in patients who underwent craniotomy or biopsy for brain tumors or brain mass lesions. Methods Patients with brain tumors or brain mass lesions undergoing surgical interventions, excluding endoscopic endonasal surgery (EES), with a diagnosis of epilepsy were eligible for this study. Patients are randomized into either Group A or B (B1 or B2) after the informed consents are taken; LEV alone in Group A patients, while LEV and SCBs in Group B patients (GroupB1, intravenous fosphenytoin plus oral lacosamide (LCM) and GroupB2, intravenous LCM plus oral LCM) were administered postoperatively. Fifty-three patients were enrolled during the first two and a half years of the study and four of them were excluded, resulting in the accumulation of 49 patients' data. Results Postoperative epileptic seizures occurred only in three out of 49 patients during the first week (6.1%) and in seven patients within two weeks after surgery (14.3%, including the three patients during the first week). In Group A, epileptic seizures occurred in two out of 26 patients during the first week (7.7%) and in five patients within two weeks (19.2%) after surgery. In Group B, epileptic seizures occurred in one out of 23 patients during the first week (4.3%) and in two patients during the first two weeks (8.7%). Low complication grade of epileptic seizures was observed in Group B rather than in Group A, however, without significant difference (p=0.256). There was no difference in the frequency of adverse effects in each group. Conclusion Although not statistically significant, the incidence of epileptic seizures within one week after surgery was lesser in LEV+SCBs groups than in LEV alone. No hepatic damage or renal function worsening occurred with the addition of LCM, suggesting the safety of LEV+SCBs therapy.

Hemispherotomy can cause post-operative strabismus.

BACKGROUND: Hemispherotomy, which involves disconnecting hemispherical fibers, is a treatment option for medically intractable epilepsy. As various neurological disorders can cause strabismus, we hypothesized that hemispherotomy can cause post-operative strabismus in patients with medically intractable epilepsy. METHODS: Nineteen patients underwent the Hirschberg test before and after hemispherical disconnection surgery. Among the 19 patients, 16 patients (six females and 10 males; mean age, 12.2 years; range, 0.17-43 years) who underwent hemispherotomy were included in this study. RESULTS: The difference in the angle between the left and right eyes was significantly widened (p = 0.025). Nine (56%) of 16 patients exhibited post-operative chronic strabismus as evaluated with the Hirschberg test. Intermittent strabismus was noticed by family members or caregivers in 10 (63%) of 16 patients. Patients older than 12 years did not show post-operative strabismus as evaluated by the Hirschberg test. CONCLUSION: Hemispherotomy can cause or worsen post-operative strabismus in pediatric patients.

The fence post depth electrode technique to control both brain tumors and epileptic seizures in patients with brain tumor-related epilepsy.

BACKGROUND: To control brain tumor-related epilepsy (BTRE), both epileptological and neuro-oncological approaches are required. We hypothesized that using depth electrodes (DEs) as fence post catheters, we could detect the area of epileptic seizure onset and achieve both brain tumor removal and epileptic seizure control. METHODS: Between August 2009 and April 2018, we performed brain tumor removal for 27 patients with BTRE. Patients who underwent lesionectomy without DEs were classified into Group 1 (13 patients) and patients who underwent the fence post DE technique were classified into Group 2 (14 patients). RESULTS: The patients were 15 women and 12 men (mean age, 28.1 years; median age 21 years; range, 5-68 years). The brain tumor was resected to a greater extent in Group 2 than Group 1 (P < 0.001). Shallower contacts showed more epileptogenicity than deeper contacts (P < 0.001). Group 2 showed better epilepsy surgical outcomes than Group 1 (P = 0.041). CONCLUSION: Using DEs as fence post catheters, we detected the area of epileptic seizure onset and controlled epileptic seizures. Simultaneously, we removed the brain tumor to a greater extent with fence post DEs than without.

Analysis for the Association Between Corpus Callosum Thickness and Corpus Callosotomy Outcomes for Patients With Epileptic Spasms or Tonic Spasms.

BACKGROUND: This retrospective study is designed to determine whether the thickness of the corpus callosum can predict corpus callosotomy outcome in pediatric patients with epileptic or tonic spasms. METHODS: We retrospectively studied 25 patients (18 boys) with intractable childhood-onset epileptic or tonic spasms who underwent corpus callosotomy between March 2008 and January 2017. Seizure outcomes were classified as favorable (class I and II of Engel's outcome classification) or unfavorable (class III and IV of Engel's outcome classification) at 12 months postoperatively. We measured the corpus callosum area on the midline and maximum cerebral area on the para-midline in sagittal magnetic resonance images just before surgery. We statistically analyzed the associations between surgical outcomes and corpus callosum area, corpus callosum area/maximum cerebral area (corpus callosum/cerebrum ratio), or age at magnetic resonance imaging just before surgery, using univariate and multivariate logistic regression analyses. RESULTS: Age at surgery ranged from six to 237 months (mean: 119). Main seizure types were epileptic spasms in 17 patients and tonic spasms in eight. Favorable outcomes occurred in 10 (40%) patients and unfavorable outcomes in 15 (60%). Both corpus callosum area and corpus callosum/cerebrum ratio did not show significant associations with the outcomes in the univariate and multivariate analyses. The 95% confidence intervals of corpus callosum/cerebrum ratio strongly overlapped between the favorable and unfavorable outcome groups. CONCLUSIONS: Our data failed to support that corpus callosum thickness on the sagittal image is associated with corpus callosotomy outcomes in pediatric patients with epileptic spasms or tonic spasms.

Side Slit Guide Pipe for Precise Placement of Depth Electrodes.

BACKGROUND: Using a stereotactic technique, surgeons can accurately place a depth electrode (DE), but sometimes the DE deviates from the intended target due to movement of the electrode or leakage of cerebrospinal fluid when placing the electrode. If DEs can be anchored before removing the catheter insertion guide pipe, more accurate placement may be possible. METHODS: We made a side slit guide pipe. When the DEs were anchored to the dura or the edge of the burr hole, the DE did not move when the guide pipe was removed. We measured the distance between the planned target and the tip of the electrode in 13 patients (3 female and 10 male patients; age range, 7-43 years; mean age 23.0 years; median age 27 years) with medically intractable epilepsy who underwent DE placement with stereotactic neuronavigation guidance. RESULTS: There were 30 DEs implanted. The mean distance from the planned target to the tip of the DE was 0.570 mm (range, 0.3-1.2 mm; median 0.5 mm; SD 0.212). The mean distance from the planned target to the tip of the DE with dural anchoring was 0.467 mm (range, 0.3-0.6 mm; median 0.45 mm; SD 0.121) and with burr hole edge anchoring was 0.596 mm (range, 0.3-1.2 mm; median 0.50 mm; SD 0.224; P = 0.205). CONCLUSIONS: DEs can be anchored using the side slit guide pipe for more precise placement.

Short duration of focal onset awareness and impaired awareness seizure are characteristic features of epilepsy in elderly patients.

PURPOSE: Diagnosing epilepsy in the elderly population can be difficult due to mimicking symptoms. Furthermore, epileptic symptoms can also be masked by various symptoms. We hypothesized that elderly patients with epilepsy exhibit specific clinical features among the various symptoms. PATIENTS AND METHODS: From 2009 to 2017, 177 patients who were older than 65 years were referred to our epilepsy center. Out of this group, the onset of symptoms occurred after reaching the age of 50 years in 152 of the patients, who were additionally being treated at our clinic. We divided their symptoms in accordance with their consciousness levels, which were defined as follows: full wakefulness level I, impaired awareness level II, and loss of consciousness level III. We also classified the duration of the symptoms as <10 seconds, ≥10 seconds but <1 minute, ≥1 minute but <5 minutes, ≥5 minutes but <10 minutes, ≥10 minutes but <1 hour, and ≥1 hour. RESULTS: Among the 152 patients analyzed (mean age 72.9 years, standard deviation 6.71, range 65-92), 84 patients had epilepsy (epilepsy group) while 68 did not exhibit epilepsy (nonepilepsy group). For the consciousness levels, there were more level I patients in the nonepilepsy vs epilepsy group (P<0.028), with symptom duration lasting <1 minute (sensitivity 0.857, specificity 1) in the epilepsy group. In contrast, there were more level II patients in the epilepsy vs the nonepilepsy group (P=0.015), with the duration of symptoms lasting <1 minute (sensitivity 0.8125, specificity 0.930) in the epilepsy group. For the level III consciousness, convulsions were more commonly seen in the epilepsy group (P=0.044). CONCLUSION: Symptoms that last <1 minute with awareness and impaired awareness might be epileptic in the elderly population.

Effectiveness of total corpus callosotomy for diffuse bilateral polymicrogyria: Report of three pediatric cases.

PURPOSE: Polymicrogyria, a malformation of the cerebral cortex, frequently causes epilepsy. Diffuse bilateral polymicrogyria (DBP) is related to poor epilepsy prognosis, but most patients with DBP are not good candidates for resective epilepsy surgery and effectiveness of corpus callosotomy (CC), a palliative surgery, for patients without resective epileptogenic cortices, has not been established in DBP. Because CC might be effective against DBP-related epilepsy, we conducted total CC in three pediatric DBP cases. METHODS: Case 1. A girl developed epilepsy at 3 months of age, with focal versive seizures and epileptic spasms. The electroencephalogram (EEG) showed a suppression-burst pattern. Total CC was performed at 6 months of age. Case 2. A female infant developed epilepsy on the day of birth, exhibiting epileptic spasms, generalized tonic-clonic seizures, and eye-deviating seizures. She had a history of clusters of tonic seizures. Total CC was performed at 1 year and 2 months of age. After CC, the epileptic focus of the tonic seizures was identified; a secondary resective surgery was conducted. Case 3. A girl developed multiple types of seizures at 3 years of age. Frequent atypical absence status was refractory to antiepileptic drugs. Total CC was conducted at 8 years of age. RESULTS: Case 1: Frequencies of both seizure types decreased. The background EEG changed to continuous high-voltage slow waves. Case 2: Clusters of tonic seizures were well-controlled. Case 3: Atypical absence seizures completely disappeared. CONCLUSION: CC could be effective for patients with DBP, whose habitual seizures include epileptic spasms and absence seizures.

Evaluation of the extent of resection and detection of ischemic lesions with intraoperative MRI in glioma surgery: is intraoperative MRI superior to early postoperative MRI?

OBJECTIVE: MRI scans obtained within 48-72 hours (early postoperative MRI [epMRI]), prior to any postoperative reactive changes, are recommended for the accurate assessment of the extent of resection (EOR) after glioma surgery. Diffusion-weighted imaging (DWI) enables ischemic lesions to be detected and distinguished from the residual tumor. Prior studies, however, revealed that postoperative reactive changes were often present, even in epMRI. Although intraoperative MRI (iMRI) is widely used to maximize safe resection during glioma surgery, it is unclear whether iMRI is superior to epMRI when evaluating the EOR, because it theoretically shows fewer postoperative reactive changes. In addition, the ability to detect ischemic lesions using iMRI has not been investigated. METHODS: The authors retrospectively analyzed prospectively collected data in 30 patients with glioma (22 and 8 patients with enhancing and nonenhancing lesions, respectively) who underwent tumor resection. These patients had received preoperative MRI within 24 hours prior to surgery, postresection radiological evaluation with iMRI during surgery, and epMRI within 24 hours after surgery, with all neuroimaging performed using identical 1.5T MRI scanners. The authors compared iMRI or epMRI with preoperative MRI, and defined a postoperative reactive change as a new postoperative enhancement or T2 high-intensity area (HIA), if this lesion was outside of the preoperative original tumor location. In addition, postoperative ischemia was evaluated on DWI. The iMRI and epMRI findings were compared in terms of 1) postoperative reactive changes, 2) evaluation of the EOR, and 3) presence of ischemic lesion on DWI. RESULTS: In patients with enhancing lesions, a new enhancement was seen in 8 of 22 patients (36.4%) on iMRI and in 12 of 22 patients (54.5%) on epMRI. In patients with nonenhancing lesions, a new T2 HIA was seen in 4 of 8 patients (50.0%) on iMRI and in 7 of 8 patients (87.5%) on epMRI. A discrepancy between the EOR measured on iMRI and epMRI was noted in 5 of the 22 patients (22.7%) with enhancing lesions, and in 3 of the 8 patients (37.5%) with nonenhancing lesions. The occurrence of ischemic lesions on DWI was found in 5 of 30 patients (16.7%) on iMRI, whereas it was found in 16 of 30 patients (53.3%) on epMRI (p = 0.003); ischemic lesions were underestimated on iMRI in 11 patients. CONCLUSIONS: Overall, given the lower incidence of postoperative reactive changes on iMRI, it was superior to epMRI in evaluating the EOR in patients with glioma, both with enhancing and nonenhancing lesions. However, because ischemic lesions can be overlooked on iMRI, the authors recommend only the additional DWI scan during the early postoperative period. Clinicians need to be mindful about not overestimating the presence of residual tumor on epMRI due to the high incidence of postoperative reactive changes.

Early Postoperative Expansion of Parenchymal High-intensity Areas on T2-weighted Imaging Predicts Delayed Cerebral Edema Caused by Carmustine Wafer Implantation in Patients with High-grade Glioma.

BACKGROUND: Carmustine (BCNU) wafer (Gliadel(®) Wafer) implantation after tumor resection is an approved treatment for high-grade glioma (HGG). These wafers change various characteristics on early postoperative magnetic resonance imaging (ep-MRI) including slight expansion of high-intensity areas on T2-weighted imaging (ep-T2-HIAs) into adjacent parenchyma without restricted diffusivity. We assessed the frequency of the ep-T2-HIAs after BCNU wafer implantation in HGG patients. Moreover, we focused on ep-T2-HIA expansion and its relation to delayed cerebral edema. METHODS: Twenty-five consecutive HGG patients who underwent BCNU wafer implantation were assessed. First, patients were divided into ep-T2-HIA and non-ep-T2-HIA groups, and the incidence of delayed adverse effects was compared between the two groups. Subsequently, the patients were divided into delayed edema and non-delayed edema groups, and pre-, intra-, and postoperative data were compared between the two groups. RESULTS: The ep-T2-HIA expansion and the delayed edema were evident in 9 cases (36%) and 12 cases (48%), respectively. In comparison of the ep-T2-HIA and non-ep-T2-HIA groups, delayed edema was the only delayed adverse effect associated with ep-T2-HIA expansion (P = 0.004). Univariate analysis showed a significantly higher ratio of delayed edema in the subgroups with maximal diameter of removed cavity ≤40 mm (P = 0.047) and the ep-T2-HIA expansion in comparison of the delayed edema and non-delayed edema groups. Multivariate analysis showed that the ep-T2-HIA expansion was the only independent factor associated with delayed edema (P = 0.021). CONCLUSION: In BCNU wafer implantation cases, ep-T2-HIA expansion was a predictive factor for delayed cerebral edema.