Arterial spin labeling (ASL) perfusion images allow noninvasive visualization of periictal hyperperfusion in epileptically activated areas occurring secondary to seizures in structural focal epilepsy, and demonstrate a close anatomical relationship between epileptogenic lesions and the activated area. A 27-year-old female patient with epilepsy presented with focal to bilateral tonic-clonic seizures. She had an extensive traumatic lesion in the perfusion area of the right middle cerebral artery (MCA), which occurred at 3 years of age. ASL with triple postlabeling delays (PLDs) imaged 1 hour after the seizure failed to reveal periictal hyperperfusion around the lesion. It was possible that because of the underdevelopment of the right internal carotid artery and MCA, the blood supply to the right hemisphere was not adequate to demonstrate ictal hypermetabolism. ASL results should be interpreted comprehensively by combining the clinical manifestations, electroencephalographic findings, and magnetic resonance (MR) imaging findings of various modalities including MR angiography.

Purpose: To describe the clinical features of postoperative involuntary movements including convulsions resulting from use of intravenous high-dose tranexamic acid (TXA) in patients undergoing cardiac and thoracic aortic surgery. We also aimed to identify associated risk factors.

Methods: This retrospective single-center study examined 191 patients who received intravenous TXA during cardiac and/or thoracic aortic surgery with cardiopulmonary bypass in our institution. Multivariable logistic regression was performed to identify independent predictors of postoperative involuntary movements/convulsions.

Results: TXA-associated involuntary movements/convulsions were observed in 25 patients (13.1%). Involuntary movements included convulsions, myoclonic jerks of limbs and/or facial muscles, and action tremors of the body, especially the head and hands. The median time from the last dose of TXA to the first involuntary movement/convulsion was 7.3 hours. The median duration of involuntary movements/convulsions was 1 day. Convulsions did not progress to status epilepticus. Intensive care unit (ICU) stay was significantly longer in patients with involuntary movements/convulsions than in those without (p < 0.001). In multivariate analysis, the following variables were independent predictors of involuntary movements/convulsions: total TXA dose (odds ratio [OR], 1.10; p = 0.047), dialysis treatment (OR, 5.32; p = 0.016), and a history of stroke (OR, 3.30; p = 0.021).

Conclusions: In addition to convulsions, myoclonus and tremors were also observed as TXA-associated involuntary movements. Although these abnormal movements generally disappeared within a short period of time, they were associated with longer ICU stay. Caution should be exercised when administering high doses of TXA to dialysis patients and patients with a history of stroke.

Vagus nerve stimulation (VNS) was performed in three patients with drug-resistant epilepsy after treatment for arteriovenous malformation (AVM). A male patient in his 40s had undergone craniotomy for a ruptured right parietal AVM in his 30s. A female patient in her 40s, and a male patient in his 50s had undergone gamma knife surgery. After VNS, all patients achieved seizure control. These results suggest that VNS is effective for controlling drug-resistant epilepsy that developed after treatment for AVM.

Background: We investigated the usefulness of the addition of arterial spin labeling (ASL) perfusion imaging to 1.5-Tesla magnetic resonance imaging (MRI) during the periictal period for the pathophysiological diagnosis of focal to bilateral tonic-clonic seizures (FBTCS) in dementia patients presenting at neurological emergency, to compensate for the weaknesses of electroencephalography (EEG).

Patients & Methods: We retrospectively examined the performance status and findings of EEG and MRI in eight dementia patients who were transported to our hospital immediately after first-onset generalized convulsive seizures.

Results: Five of the eight patients were transported outside of consultation hours, while three were transported within consultation hours. MRI was performed 1 to 7 h (mean, 2.8 h) after arrival, while EEG 2 h to 2 days (mean, 15.1 h). In addition, MRI was performed first in seven patients, and EEG was done first in only one patient. ASL demonstrated focal hyperperfusion in all patients. In Patients 1 and 2, periictal hyperperfusion was observed around the organic lesions, indicating the pathophysiology of structural focal epilepsy and acute symptomatic seizure, respectively. In Patients 3–8, periictal hyperperfusion was noted in one cerebral hemisphere or the apex of bilateral frontotemporal lobes unrelated to the organic lesions, which led to a suspicion of dementia-related epilepsy. In contrast, paroxysmal discharges were observed on EEG in only three patients, and their locations were consistent with the hyperperfusion identified on ASL. Focal slow waves, the location of which matched the ASL findings, were observed in one patient. However, a pathophysiological diagnosis could not be made from the EEG findings alone in the other patients.

Conclusion: At our hospital, ASL was almost always performed prior to EEG. Capturing periictal ASL hyperperfusion first may improve the ability to make a prompt pathophysiological diagnosis of FBTCS associated with dementia.

Background: Transient epileptic amnesia (TEA) is a special type of mesial temporal lobe epilepsy manifesting recurrent amnesia attacks as the main symptom. Patients with TEA often demonstrate two other types of memory symptoms: accelerated long-term forgetting (ALF) and autobiographical amnesia (AbA). In our previous reports, we presented two clinical cases in which the patients showed symptoms of ALF and/or AbA without any type of epileptic seizure, including TEA attacks. Based on these cases and a literature search, we proposed a new clinical entity, which we named ‘transient epileptic amnesia complex syndrome (TEACS)’. We also proposed a new type of neurocognitive disorder, which we named ‘epileptic cognitive impairment resembling Alzheimer's disease (ECI-A)’.

Methods and Results: The clinical profiles and characteristics of three cases of TEACS and one case of ECI-A are presented. Based on the clinical courses of these cases, pathological hypotheses regarding TEACS and ECI-A are discussed, and the importance of clearly recognizing a new concept in epileptology is emphasized.

Discussion: We consider that at least two non-paroxysmal and chronic epilepsy-related disorders (TEACS and ECI-A) exist. The two disorders are considered to be caused by continual excessive neuronal discharges that are not sufficient to give rise to clinical seizures. The establishment of these new entities would open up therapeutic possibilities for such non-paroxysmal and chronic epilepsy-related disorders.

We herein report a case of epilepsy in an adolescent patient with epilepsy whose chief complaints at presentation were abnormal behavior and intellectual deterioration. The patient, a Japanese adolescent female, first visited our department following an episode of twilight state, without any prior seizure history. On physical examination, no neurological abnormalities were noted. Magnetic resonance imaging revealed no abnormalities. During a conventional electroencephalographic (EEG) examination, an ictal EEG was incidentally recorded, showing a 30-second ictal focal seizure with impairment of consciousness. Detailed investigations were performed at Okayama University Hospital but no other abnormal findings were reported. Her seizures were resolved soon after treatment with levetiracetam The Wechsler Intelligence Scale for Children test before the start of treatment revealed an IQ of 67, which increased to 107 after several months of treatment with levetiracetam. We concluded that the patient's unusual symptoms at presentation were caused by frequent focal seizures mixed with a postictal state.

Purpose: Electroencephalogram (EEG) is a fundamental diagnostic tool for epilepsy. However, it is difficult to determine abnormal signals such as spike and wave discharges in some EEG waveforms. This study aimed to compare machine learning (ML) and physician-annotated readings for the same EEG data.

Methods: Ten abnormal interictal EEG recordings from patients with childhood epilepsy with centrotemporal spikes were selected for analysis. Five EEG recordings were examined by two medical doctors to build an ML model with a convolutional neural network. Five additional EEG recordings were manually labeled by two medical doctors, two clinical technicians familiar with EEG, and one novice university student as evaluating datasets. The statistical sensitivity, specificity, area under the receiver operating characteristic curve (AUC), accuracy, precision, and recall of the ML model for each evaluating group were obtained. The label match ratio was determined as the ratio of the number of matched labels to the number of all labels manually annotated by the annotator.

Results: The total annotation count was 37,752 (7,167 for training and 30,585 for testing). The mean label match ratio was 98.9% and the lowest was 93.0%. The sensitivity was 99%. The AUC for ML was > 0.95, and the novice student had a lower AUC with statistical significance. The label match ratio did not show a significant difference.

Conclusion: ML models are candidate training tools for EEG analysis.

Magnetoencephalography (MEG) is an established functional brain imaging modality that was initially developed about 50 years ago and is currently used as a clinical tool for non-invasive assessment of human brain function. The temporal resolution of MEG and electroencephalography (EEG) are identical, although MEG offers many advantages over scalp EEG recordings in terms of localizing epileptic foci and eloquent cortex. Namely, MEG measurements are minimally distorted by cephalic tissue compared to EEG measurements. In this mini-review, we briefly examine the clinical utility of MEG in epilepsy and provide a demographic overview of MEG scans at our institution. The primary focus, however, is on recent developments in MEG technology that address the challenges faced by MEG systems.

Background: We investigated the usefulness and limitations of adding arterial spin labeling (ASL) perfusion imaging to 1.5-Tesla magnetic resonance imaging (MRI) to compensate for the weakness of routine electroen-cephalography (EEG) in the pathophysiological diagnosis of post-intracerebral hemorrhage (ICH) epilepsy (PICHE) at neuroemergency.

Patients & Methods: Five patients who developed PICHE and were immediately admitted to our hospital between August 2023 and January 2024 were studied. Patients 1-3 developed PICHE within 2 years after ICH onset, whereas patients 4 and 5 developed PICHE after more than 12 years. We retrospectively analyzed the performance status and MRI and EEG findings of each patient during the periictal and interictal states.

Results: MRI was performed within 1 h of arrival in all patients. On the other hand, EEG was performed within 1 h in patients 1 and 2, who were transported during weekday hours, but 1-2 days later in patients 3-5, who were transported outside the consultation hours. In patients 1-3, periictal ASL showed focal hyperperfusion related to the site of cortical involvement due to the ICH and corticotomy performed during surgery. EEG revealed paroxysmal discharges almost corresponding to the site of periictal ASL hyperperfusion. However, ASL demonstrated the pathophysiological mechanism of structural focal epilepsy more clearly. In patients 4 and 5, on the contrary, the periictal ASL showed no focal hyperperfusion. MR angiography (MRA) showed markedly poor visualization of the ipsilateral peripheral middle cerebral artery (MCA), and the ipsilateral hemisphere showed a marked decrease in blood flow on the interictal ASL.

Conclusion: Capturing periictal ASL hyperperfusion can improve the diagnosis of PICHE. However, in cases of PICHE occurring long after ICH onset, degeneration and regression of the affected MCA may occur in addition to primary damage to the MCA that supplies periictal hyperperfusion, making the visualization of periictal hyperperfusion difficult. Therefore, evaluations in conjunction with other modalities such as MRA and EEG are necessary.