Cortical Involvement Research Articles

Long-Term Neurologic Outcomes in Pediatric Arterial Ischemic Stroke: The Impact of Age and Lesion Location.

The impact of age-at-stroke on outcome following pediatric arterial ischemic stroke remains controversial. We studied the interaction of age-at-stroke and infarct location and extent with long-term neurological outcomes. We conducted a longitudinal prospective outcome study of children with acute pediatric arterial ischemic stroke diagnosed from 1996 to 2016 at the Hospital for Sick Children, Toronto, Canada. Pediatric Stroke Outcome Measure scores were dichotomized as normal or abnormal (ie, mild, moderate, or severe). Outcomes were analyzed by age-at-stroke (newborn: birth to 28 days; early childhood: 29 days to 5 years; middle/late childhood: >5-18 years), and infarct location, based on each of the following: model 1: circulation (anterior/posterior); model 2: cortical versus subcortical involvement; and model 3: specific arterial territory, including infarct extent (small [<50% arterial territory] or large [≥50%]). Univariable and multivariable logistic regression models were fitted. Among 285 children, the outcome at median 6.1 years was 43.5% abnormal. Controlling for infarct location, increasing age-at-stroke was associated with increasing abnormal outcome. Model 1 demonstrated that, compared with neonates, abnormal outcomes were increased in early childhood (adjusted odds ratio [aOR], 2.91 [95% CI, 1.24-7.05]) and more so in middle/late childhood (aOR, 4.46 [95% CI, 1.71-12.13]). Outcomes were worse for combined locations, including anterior+posterior (model 1: aOR, 15.4 [95% CI, 4.49-64.63]) and cortical+subcortical (model 2: aOR, 10.7 [95% CI, 3.88-32.74]). Abnormal outcomes were also increased for anterior circulation (model 1: aOR, 14.91 [95% CI, 5.29-54.21]) and subcortical locations (model 2: aOR, 4.36 [95% CI, 1.37-14.95]). Among individual arterial territories, outcomes were best for superior division middle cerebral artery (100% normal) and worst for lateral lenticulostriate artery infarcts (47.4% abnormal; model 3: aOR, 14.2 [95% CI, 3.5-67.6]). Among survivors of pediatric stroke, abnormal long-term neurological outcome is increased with increasing age-at-stroke, supporting enhanced plasticity after focal injury to the newborn brain compared with older pediatric ages.

Study of the Brain Functional Connectivity Processes During Multi-Movement States of the Lower Limbs.

Studies using source localization results have shown that cortical involvement increased in treadmill walking with brain-computer interface (BCI) control. However, the reorganization of cortical functional connectivity in treadmill walking with BCI control is largely unknown. To investigate this, a public dataset, a mobile brain-body imaging dataset recorded during treadmill walking with a brain-computer interface, was used. The electroencephalography (EEG)-coupling strength of the between-region and within-region during the continuous self-determinant movements of lower limbs were analyzed. The time-frequency cross-mutual information (TFCMI) method was used to calculate the coupling strength. The results showed the frontal-occipital connection increased in the gamma and delta bands (the threshold of the edge was >0.05) during walking with BCI, which may be related to the effective communication when subjects adjust their gaits to control the avatar. In walking with BCI control, the results showed theta oscillation within the left-frontal, which may be related to error processing and decision making. We also found that between-region connectivity was suppressed in walking with and without BCI control compared with in standing states. These findings suggest that walking with BCI may accelerate the rehabilitation process for lower limb stroke.

MELAS Presenting as Bilateral Symmetric Occipital and Temporal Cortices Lesions: A Case Report and Literature Review.

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episode (MELAS) is one of the most common maternally inherited mitochondrial diseases. The stroke-like episode affecting the cortical cortex is the hallmark of MELAS; however, it rarely presents as simultaneously bilateral symmetric cortices lesions. We reported a case of MELAS in a 46-year-old female patient with bilateral symmetric occipital and internal temporal cortices involvements on brain magnetic resonance imaging (MRI). A literature review of MELAS patients and a retrospective analysis were performed. She had a family history of diabetes. Although she denied a history of diabetes, elevated blood glucose was noted after admission, and diabetes was diagnosed. Laboratory examination revealed elevated lactate acid and creatine kinase levels in blood. Cranial computed tomography (CT) image demonstrated basal ganglia calcification, as well as subtle decreased attenuation in bilateral symmetric occipital and internal temporal cortices. Brain magnetic resonance imaging (MRI) demonstrated symmetric gyriform hyperintensity in bilateral occipital lobes and internal temporal lobes in both grey and white matter on fluid-attenuated inversion recovery (FLAIR) images with restricted diffusion on diffusion weighted images (DWI). A genetic test revealed a point mutation in the mtDNA(3243A > G) by blood examination. Literature review showed that there were 231 eligible patients with MELAS identified from 212 published papers. Symmetric cortical involvements were seen in 15 (6.5%) patients on brain MRI. MELAS should be considered as a potential diagnosis in the patients with bilateral symmetric stroke-like cortices lesions.

Resting-state brain activation patterns and network topology distinguish human sign and goal trackers

The “Sign-tracker/Goal-tracker” (ST/GT) is an animal model of individual differences in learning and motivational processes attributable to distinctive conditioned responses to environmental cues. While GT rats value the reward-predictive cue as a mere predictor, ST rats attribute it with incentive salience, engaging in aberrant reward-seeking behaviors that mirror those of impulse control disorders. Given its potential clinical value, the present study aimed to map such model onto humans and investigated resting state functional magnetic resonance imaging correlates of individuals categorized as more disposed to sign-tracking or goal-tracking behavior. To do so, eye-tracking was used during a translationally informed Pavlovian paradigm to classify humans as STs (n = 36) GTs (n = 35) or as Intermediates (n = 33), depending on their eye-gaze towards the reward-predictive cue or the reward location. Using connectivity and network-based approach, measures of resting state functional connectivity and centrality (role of a node as a hub) replicated preclinical findings, suggesting a major involvement of subcortical areas in STs, and dominant cortical involvement in GTs. Overall, the study strengthens the translational value of the ST/GT model, with important implications for the early identification of vulnerable phenotypes for psychopathological conditions such as substance use disorder.

Role of Advanced Magnetic Resonance Imaging in Differentiating among Glioma Subtypes and Predicting Tumor-Proliferative Behavior

Abstract Objective Gliomas are a devastating and heterogeneous group of primary brain tumors. Previously, the source of glioma was undetermined. Recent literature indicates that neural stem cells, or progenitors, are proposed to be the source of glioma. The prognosis of different types of gliomas differs due to their various biological tissue types. Besides the histological grade, the two useful immunohistochemistry markers that show the tumor's biological behavior are isocitrate dehydrogenase (IDH) labeling and the Ki-67 labeling index. We sought to determine the magnetic resonance imaging (MRI) characteristics associated with IDH mutational status and ascertain whether MRI combined with IDH mutational status, can better predict the clinical outcomes of gliomas. Materials and Methods This period study was conducted in the Department of Radiology, Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu, India for 5 years (May 2016–May 2021). The study cohort included 30 patients diagnosed with gliomas who underwent preoperative MRI followed by surgical resection and histopathological examination. Preoperative MRI images were done to assess qualitative tumor characteristics such as location, margin of tumor, extent, cortical involvement, cystic component, mineralization or hemorrhage, and contrast enhancement. Discussion Differences in MRI features between IDH-mutant (MT) and IDH-wild-type (WT) groups were analyzed using the chi-square test for categorical variables and the Mann–Whitney U test for continuous variables. Statistical analysis was conducted using SPSS software. Results Among the 30 patients evaluated, 18 had IDH-WT and 12 had IDH-MT type gliomas. Male predominance (73.33%) was noted in our study. Brainstem location, indistinct borders (83.33%), less cortical involvement (72.22%), less cystic changes (88.89%), more area of necrotic component (44.44%), significantly increased choline/creatine (Cho/Cr) ratio, and choline/N-acetyl aspartate (Cho/NAA) ratio favors IDH-WT tumors. Positive T2-fluid-attenuated inversion recovery mismatch sign is more frequently seen in IDH-MT (7/12; 58.33%) tumors than in IDH-WT (4/18; 22.22%) tumors. Whereas well-defined contours (66.67%), more cortical involvement (83.33%), more cystic changes (58.33%), and less area of necrotic component favor IDH-MT type tumors. Conclusion MRI is a very promising and valuable tool for differentiating among glioma subtypes and predicting tumor-proliferative behavior in glioma cases. The combination of MRI characteristics with IDH mutation status enhances the predictive accuracy for clinical outcomes in glioma patients. This approach could potentially guide treatment planning and improve prognostic assessments.

Incidence and risk factors of post-stroke seizure among ischemic stroke patients

BackgroundPost-stroke seizure (PSS) increases morbidity and mortality after ischemic stroke, but a comprehensive understanding of its incidence and risk factors is lacking. We report the rate and risk factors of PSS at a single institution. MethodsA retrospective cohort study of adult acute ischemic stroke patients between 2018 and 2022 at a comprehensive stroke center was conducted. Patients with a history of seizures, additional stroke during index admission, or death within 7 days of stroke onset were excluded. Early PSS was defined as a new seizure occurring ≤7 days after stroke onset, while late PSS occurred >7 days after stroke onset. Multivariable logistic regression and cox proportional hazard analysis was conducted. Results1211 participants met inclusion criteria. Patients were a mean age of 67.82 and were primarily male (58.7 %), white (72.6 %), and non-Hispanic (91.9 %). Incidence of PSS was 8.8 % (n = 106), of which 53.8 % (n = 57) were early and 46.2 % (n = 49) were late. Bivariate analysis identified younger age, diabetes, baseline National Institutes of Health Stroke Scale (NIHSS), Alberta Stroke Program Early Computed Tomography Score ≤5, cortical involvement, and hemorrhagic transformation as significant in the development of PSS. Multivariable cox proportional hazard analysis identified cortical involvement (hazard ratio [HR]: 2.31, 95 % confidence interval [CI] [1,29, 4.14]), NIHSS ≥ 21 (HR: 1.82, 95 % CI [1.02, 3.22]),and younger age (HR: 0.97, 95 % CI [0.96, 0.98]) as significant PSS predictors. ConclusionPSS occurred in 8.8 % of patients presenting with ischemic stroke. Hemorrhagic transformation, cortical involvement, high NIHSS, and younger age were significant predictors of PSS.

Ictal and interictal epileptic networks of 34 patients with Hypothalamic Hamartoma on scalp electroencephalography.

To investigate ictal and interictal cortical involvement in epilepsy associated with hypothalamic hamartoma. We conducted a retrospective study of 34 patients with epilepsy and hypothalamic hamartoma, using data from long-term video-EEG-monitoring. We analyzed onset and propagation of ictal and interictal scalp EEG and visualized the resulting networks of cortical involvement. According to clinical and EEG criteria we grouped patients in: (1) focal disease, (2) focal advanced disease, (3) extended disease. We compared networks between these groups and different seizure types. Eight patients underwent several video-EEGs, and we analyzed all to investigate epilepsy progression. Epileptic activity mainly involved frontal and temporal cortex regions. Involvement of frontal regions was more common in advanced stages of the disease, and strong fronto-temporal connections were observed in the ictal networks of patients in intermediate stages (25.0% (left) and 35.7% (right) of seizures with EEG correlate). Occurrence and timing of EEG-correlate significantly depended on the seizure type (Chi-2-test, p<<0.001). In patients with several EEGs, seizure activity increased by +0.67 seizures/day/month (mean). There were significant differences between patients with normal and impaired cognitive function, with the latter showing pronounced ictal involvement of fronto-temporal cortex areas (p<0.001). Overall, in epilepsy due to hypothalamic hamartoma, cortical involvement focuses on frontal and temporal regions and varies systematically with the stage of the disease, different seizure types and presence of impaired cognitive function. We propose that these data may help improve our general understanding of epileptogenesis and potentially provide insights for the surgical therapy of hypothalamic hamartomas.

Scrub Typhus Meningoencephalitis Presenting as Generalized Convulsive Status Epilepticus with Basal Ganglia and Extra-limbic Cortical Involvement, Complicated by Cortical Multifocal Myoclonus

Background Scrub typhus is an acute febrile infectious disease highly prevalent in the Asia Pacific region, often referred to as the “tsutsugamushi triangle.” This mite-borne rickettsial zoonosis is caused by Orientia tsutsugamushi, an intracellular Gram-negative organism that primarily targets endothelial cells. The resulting vasculitis leads to multisystem involvement. In terms of neurological manifestations, meningoencephalitis is the most common presentation of scrub typhus. Other frequent neurological manifestations include cranial nerve paresis, transverse myelitis, and polyneuropathy. Status epilepticus, while reported, is a rare presenting feature of this infection. Although scrub typhus has been documented to present as limbic encephalitis, there have been no previous descriptions in the literature of neuroradiological patterns affecting the basal ganglia or extra-limbic cortices in this condition. Case Report We report a case of a 23-year-old previously healthy woman who presented with scrub typhus meningoencephalitis. The condition manifested as encephalitis with involvement of the basal ganglia and extra-limbic cortices. She presented with generalized convulsive status epilepticus, which was complicated by cortical multifocal myoclonus. Discussion Scrub typhus can be a significant diagnostic challenge, potentially presenting with generalized convulsive status epilepticus and mimicking both clinical and radiological features of arboviral encephalitides, such as those caused by West Nile and Japanese encephalitis viruses. Furthermore, as demonstrated in this case, its radiological presentation can resemble that of autoimmune encephalitis. Given that scrub typhus is amenable to treatment with antibiotics, such as doxycycline and azithromycin, which do not increase seizure risk, it should be considered in the differential diagnosis for patients presenting with seizures or encephalitis, especially in endemic areas.

Cortical activation in REM behavior disorder mimics voluntary movement. An electroencephalography study

ObjectivesMotor symptoms of Parkinson’s disease improve during REM sleep behavior disorder movement episodes. Our aim was to study cortical activity during these movement episodes, in patients with and without Parkinson’s disease, in order to investigate the cortical involvement in the generation of its electromyographic activity and its potential relationship with Parkinson’s disease. MethodsWe looked retrospectively in our polysomnography database for patients with REM sleep behavior disorder, analyzing fifteen patients in total, seven with idiopathic REM sleep behavior disorder and eight associated with Parkinson’s disease. We selected segments of REM sleep with the presence of movements (evidenced by electromyographic activation), and studied movement-related changes in cortical activity by averaging the electroencephalographic signal (premotor potential) and by means of time/frequency transforms. ResultsWe found a premotor potential and an energy decrease of alpha–beta oscillatory activity preceding the onset of electromyographic activity, together with an increase of gamma activity for the duration of the movement. All these changes were similarly present in REM sleep behavior disorder patients with and without Parkinson’s disease. ConclusionsMovement-related changes in electroencephalographic activity observed in REM sleep behavior disorder are similar to those observed during voluntary movements, regardless of the presence of Parkinson’s disease motor symptoms. SignificanceThese results suggest a main involvement of the cortex in the generation of the movements during REM sleep.

Revascularization Therapies for Ischemic Stroke and Association With Risk of Epilepsy: A Danish Nationwide Register-Based Study.

The association between stroke revascularization therapies and poststroke epilepsy is only sparsely investigated, and results are conflicting. The aim of this study is to investigate whether stroke revascularization therapies are associated with different risks of poststroke epilepsy. We conducted a nationwide, register-based, propensity score-matched cohort study. We identified 40 816 patients admitted with a first ischemic stroke and no prior history of epilepsy in Denmark between January 1, 2011, and December 16, 2018. Of these, 6541 were treated with thrombolysis, 379 with thrombectomy, and 1005 with both thrombolysis and thrombectomy. The 3 treatment groups were each matched 1:1 to patients with stroke not treated with revascularization. Exact matching was done for sex, while propensity scores included information on stroke severity, cortical involvement, age, comorbidities, and socioeconomic parameters. Outcome was any diagnosis of epilepsy. We used Cox regressions to estimate adjusted hazard ratios (HRs) of epilepsy after ischemic stroke. Compared with matched patients with ischemic stroke not receiving revascularization treatment, patients who received thrombolysis alone had 32% lower risk of epilepsy (adjusted HR, 0.68 [95% CI, 0.57-0.81]) and patients who received thrombolysis and thrombectomy had 45% lower risk of epilepsy (adjusted HR, 0.55 [95% CI, 0.41-0.73]). Thrombectomy alone was not associated with significantly lower risk of epilepsy compared with matched patients with ischemic stroke not receiving revascularization therapy (adjusted HR, 0.78 [95% CI, 0.57-1.29]). Thrombolysis alone and in combination with thrombectomy in ischemic stroke was associated with lower risk of epilepsy, whereas thrombectomy alone was not associated with lower risk of epilepsy.

Related factors of acute symptomatic seizures and epilepsy in children with myelin oligodendrocyte glycoprotein antibody-associated disease

Objective: To investigate the risk factors of acute symptomatic seizures (ASS) and epilepsy in children with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: A ambispective cohort study was used including 74 children with MOGAD who were admitted to the Department of Pediatrics of Peking University First Hospital from January 2013 to June 2023 and were followed up. Demographic information, clinical information, treatment status, ASS and epilepsy status were collected. The clinical phenotypes were classified. According to the presence or absence of ASS in the course of disease, the children and the course of disease were divided into groups with and without ASS. Chi-square test, Fisher exact test and Mann Whitney U test were used to analyze the correlation between symptoms and auxiliary examination characteristics and the occurrence of ASS in the two groups of children. Multivariate Logistic regression analysis was used for multivariate analysis. Results: The onset age of the 74 children with MOGAD was 6.58 (3.80, 9.67) years, including 38 females (51.4%) and 36 males (48.6%). The duration of the final follow-up was 2.67 (1.10, 4.12) years, with a total of 239 times acute clinical episodes. ASS occurred in 39.2% (29/74) children during the course of disease and in 29.3% (70/239) of attacks. The common phenotypes were ADEM (67 times (28.0%)), optic neuritis (37 times (15.4%)) and cerebral cortical encephalitis (31 times (13.0%)) in 239 times acute clinical episodes. The incidence of ASS in ADEM and cerebral cortical encephalitis phenotype was 28.4%(19/67) and 100.0% (31/31), respectively. Multivariate analysis showed that cortical involvement on magnetic resonance imaging during clinical attacks was an independent risk factor for ASS (β=-1.49, OR=0.23) after excluding attacks involving only optic nerve or spinal cord (49 episodes). During the follow-up, 5 children (6.8%) had epilepsy, and all children with epilepsy had multiple clinical attacks of MOGAD and previous ASS. Conclusions: Cortical involvement on magnetic resonance imaging during clinical episodes is an independent risk factor for ASS in children with MOGAD. All MOGAD children with epilepsy had ASS and multiple MOGAD clinical episodes in the past.

Dynamic Evolution of Infarct Volumes at MRI in Ischemic Stroke Due to Large Vessel Occlusion.

The typical infarct volume trajectories in stroke patients, categorized as slow or fast progressors, remain largely unknown. This study aimed to reveal the characteristic spatiotemporal evolutions of infarct volumes caused by large vessel occlusion (LVO) and show that such growth charts help anticipate clinical outcomes. We conducted a secondary analysis from prospectively collected databases (FRAME, 2017-2019; ETIS, 2015-2022). We selected acute MRI data from anterior LVO stroke patients with witnessed onset, which were divided into training and independent validation datasets. In the training dataset, using Gaussian mixture analysis, we classified the patients into 3 growth groups based on their rate of infarct growth (diffusion volume/time-to-imaging). Subsequently, we extrapolated pseudo-longitudinal models of infarct growth for each group and generated sequential frequency maps to highlight the spatial distribution of infarct growth. We used these charts to attribute a growth group to the independent patients from the validation dataset. We compared their 3-month modified Rankin scale (mRS) with the predicted values based on a multivariable regression model from the training dataset that used growth group as an independent variable. We included 804 patients (median age 73.0 years [interquartile range 61.2-82.0 years]; 409 men). The training dataset revealed nonsupervised clustering into 11% (74/703) slow, 62% (437/703) intermediate, and 27% (192/703) fast progressors. Infarct volume evolutions were best fitted with a linear (r = 0.809; p < 0.001), cubic (r = 0.471; p < 0.001), and power (r = 0.63; p < 0.001) function for the slow, intermediate, and fast progressors, respectively. Notably, the deep nuclei and insular cortex were rapidly affected in the intermediate and fast groups with further cortical involvement in the fast group. The variable growth group significantly predicted the 3-month mRS (multivariate odds ratio 0.51; 95% CI 0.37-0.72, p < 0.0001) in the training dataset, yielding a mean area under the receiver operating characteristic curve of 0.78 (95% CI 0.66-0.88) in the independent validation dataset. We revealed spatiotemporal archetype dynamic evolutions following LVO stroke according to 3 growth phenotypes called slow, intermediate, and fast progressors, providing insight into anticipating clinical outcome. We expect this could help in designing neuroprotective trials aiming at modulating infarct growth before EVT.

P.049 Acetazolamide use for myoclonus: case report of 2 patients with progressive myoclonic epilepsy and literature review

Background: Cortical myoclonus originates at cerebral cortex, predominantly occurring on voluntary movements. Few case reports described usage of Acetazolamide (ACZ) for myoclonus. Methods: Chart review of 2 patients was performed. Literature review was conducted on myoclonus and ACZ using Pubmed. Results: 22-year-old female was diagnosed with Progressive Myoclonic Epilepsy (PME) secondary to a KCNC1 mutation. Her symptoms started at 10 years old with bilateral tonic clonic seizures (BTCS), later developing progressive ataxia and myoclonus, involving face and limbs, which worsened with stimulus and menses. Medications included Perampanel, Clonazepam and Levetiracetam, however myoclonus was still limiting. At the age of 19, ACZ 250 mg BID was started for 2 weeks around her menses. Follow up revealed significant improvement of myoclonus, resulting in better ambulation, balance and speech, sustained 2.5 years after. 67-year-old male presented BTCS at the age of 53 along with cortical myoclonus, dementia and ataxia, leading to diagnosis of PME with a mutation on IRF2BPL. Improvement of myoclonus occurred with ACZ 250 mg BID biweekly, although balance and cognition still deteriorated. Conclusions: Previous literature outlines 4 cases of action myoclonus that responded to ACZ. We believe that ACZ should be considered to treat myoclonus, especially in cases with cortical involvement and hormonal fluctuations.

EEG Innovations in Neurological Disorder Diagnostics: A Five-Year Review

The study provides a description of electroencephalography (EEG) advancements and their application in diagnosing and assessing various neurological diseases over the previous five years. The paper covers how EEG is used to examine epilepsy, sleep disorders, movement disorders, cognitive function, and brain damage. In epilepsy, EEG remains critical for seizure diagnosis, categorization, and localization of epileptogenic zones. Recent enhancements include the integration of machine learning techniques with high-density EEG equipment. In terms of sleep disorders, aberrant patterns suggestive of illnesses such as sleep apnea or narcolepsy may be diagnosed by a sleep architecture study utilizing EEGs, which can also be used to track therapy response. Cortical involvement occurs in Parkinson’s disease and Huntington’s disease, as well as other areas of the brain stem or basal ganglia. It helps researchers learn more about the cortical damage produced by these disorders, which contributes greatly to understanding their pathophysiology. Aside from that, cognitive evaluation based on EEG has evolved via the creation of quantifiable biomarkers for early identification and monitoring of deterioration in Alzheimer’s disease, among others. Traumatic injuries can damage brain functioning, hence knowledge regarding severity predicted outcomes can be acquired by Traumatic Brain Injury evaluation utilizing EEG.

Myoepithelial Tumors of Bone With EWSR1::PBX3 Fusion: A Spectrum From Benign to Malignant

The EWSR1::PBX3 fusion gene, commonly associated with cutaneous syncytial myoepitheliomas, is also found in myoepithelial tumors (METs) of bone and soft tissue. These tumors typically demonstrate benign histology and favorable outcomes. This study examines 6 previously unreported intraosseous METs harboring the EWSR1::PBX3 fusion, focusing on their histopathologic characteristics, immunophenotype, clinical and radiographic profiles, and patient outcomes. The cohort comprised 5 men and 1 woman, aged 25 to 65 years (median age: 31 years), with tumors located in the proximal tibia (3 cases), distal radius (2 cases), and ilium (1 case) and sizes between 3.2 and 12.2 cm (median size: 3.9 cm). Imaging showed osteolytic lesions with varying degrees of cortical involvement and soft tissue extension in 3 cases. Histologically, 4 tumors showed mainly uniform oval-to-spindled cells in syncytial or fascicular arrangements within a collagenous matrix, displaying either bland nuclear features or mild atypia, and low to slightly elevated mitotic activity (≤1 per 10 high-power fields in 3 cases and 6 per 10 high-power fields in 1), classifying them as benign or atypical METs. In contrast, 2 tumors exhibited pronounced nuclear atypia with ovoid, spindled, epithelioid and round cells, hyperchromatic nuclei, inconspicuous nucleoli, increased N/C ratios, high mitotic rates (17 and 19 per 10 high-power fields), and extensive necrosis. Both tumors behaved aggressively—one patient underwent amputation after neoadjuvant chemotherapy and radiation, and the other died within 7 months with the disease still present. Immunohistochemically, the tumors consistently expressed epithelial membrane antigen and S100 but lacked keratin (AE1/AE3) expression. Our study demonstrated that bone METs with EWSR1::PBX3 fusions encompass a histologic continuum from benign to malignant, with benign/atypical METs mirroring their cutaneous analogs in morphology, and malignant variants distinguished by heterogeneous cytologic and architectural features, pronounced nuclear atypia, and high mitotic rates.

Deciphering seizure semiology in corpus callosum injuries: A comprehensive systematic review with machine learning insights

IntroductionSeizure disorders have often been found to be associated with corpus callosum injuries, but in most cases, they remain undiagnosed. Understanding the clinical, electrographic, and neuroradiological alternations can be crucial in delineating this entity. ObjectiveThis systematic review aims to analyze the effects of corpus callosum injuries on seizure semiology, providing insights into the neuroscientific and clinical implications of such injuries. MethodsAdhering to the PRISMA guidelines, a comprehensive search across multiple databases, including PubMed/Medline, NIH, Embase, Cochrane Library, and Cross-ref, was conducted until September 25, 2023. Studies on seizures associated with corpus callosum injuries, excluding other cortical or sub-cortical involvements, were included. Machine learning (Random Forest) and deep learning (1D-CNN) algorithms were employed for data classification. ResultsInitially, 1250 articles were identified from the mentioned databases, and additional 350 were found through other relevant sources. Out of all these articles, 41 studies met the inclusion criteria, collectively encompassing 56 patients The most frequent clinical manifestations included generalized tonic-clonic seizures, complex partial seizures, and focal seizures. The most common callosal injuries were related to reversible splenial lesion syndrome and cytotoxic lesions. Machine learning and deep learning analyses revealed significant correlations between seizure types, semiological parameters, and callosal injury locations. Complete recovery was reported in the majority of patients post-treatment. ConclusionCorpus callosum injuries have diverse impacts on seizure semiology. This review highlights the importance of understanding the role of the corpus callosum in seizure propagation and manifestation. The findings emphasize the need for targeted diagnostic and therapeutic strategies in managing seizures associated with callosal injuries. Future research should focus on expanding the data pool and exploring the underlying mechanisms in greater detail.

The Association of Epileptic Seizures after Acute Ischemic Stroke with Cerebral Cortical Involvement and Electroencephalographic Changes.

Background and objectives: while acute ischemic stroke is the leading cause of epilepsy in the elderly population, data about its risk factors have been conflicting. Therefore, the aim of our study is to determine the association of early and late epileptic seizures after acute ischemic stroke with cerebral cortical involvement and electroencephalographic changes. Materials and methods: a prospective cohort study in the Hospital of the Lithuanian University of Health Sciences Kaunas Clinics Department of Neurology was conducted and enrolled 376 acute ischemic stroke patients. Data about the demographical, clinical, radiological, and encephalographic changes was gathered. Patients were followed for 1 year after stroke and assessed for late ES. Results: the incidence of ES was 4.5%, the incidence of early ES was 2.7% and the incidence of late ES was 2.4%. The occurrence of early ES increased the probability of developing late ES. There was no association between acute cerebral cortical damage and the occurrence of ES, including both early and late ES. However, interictal epileptiform discharges were associated with the occurrence of ES, including both early and late ES.

MRI Scoring Systems for Predicting Isocitrate Dehydrogenase Mutation and Chromosome 1p/19q Codeletion in Adult-type Diffuse Glioma Lacking Contrast Enhancement.

Background According to 2021 World Health Organization criteria, adult-type diffuse gliomas include glioblastoma, isocitrate dehydrogenase (IDH)-wildtype; oligodendroglioma, IDH-mutant and 1p/19q-codeleted; and astrocytoma, IDH-mutant, even when contrast enhancement is lacking. Purpose To develop and validate simple scoring systems for predicting IDH and subsequent 1p/19q codeletion status in gliomas without contrast enhancement using standard clinical MRI sequences. Materials and Methods This retrospective study included adult-type diffuse gliomas lacking contrast at contrast-enhanced MRI from two tertiary referral hospitals between January 2012 and April 2022 with diagnoses confirmed at pathology. IDH status was predicted primarily by using T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign, followed by 1p/19q codeletion prediction. A visual rating of MRI features, apparent diffusion coefficient (ADC) ratio, and relative cerebral blood volume was measured. Scoring systems were developed through univariable and multivariable logistic regressions and underwent calibration and discrimination, including internal and external validation. Results For the internal validation cohort, 237 patients were included (mean age, 44.4 years ± 14.4 [SD]; 136 male patients; 193 patients in IDH prediction and 163 patients in 1p/19q prediction). For the external validation cohort, 35 patients were included (46.1 years ± 15.3; 20 male patients; 28 patients in IDH prediction and 24 patients in 1p/19q prediction). The T2-FLAIR mismatch sign demonstrated 100% specificity and 100% positive predictive value for IDH mutation. IDH status prediction scoring system for tumors without mismatch sign included age, ADC ratio, and morphologic characteristics, whereas 1p/19q codeletion prediction for IDH-mutant gliomas included ADC ratio, cortical involvement, and mismatch sign. For IDH status and 1p/19q codeletion prediction, bootstrap-corrected areas under the receiver operating characteristic curve were 0.86 (95% CI: 0.81, 0.90) and 0.73 (95% CI: 0.65, 0.81), respectively, whereas at external validation they were 0.99 (95% CI: 0.98, 1.0) and 0.88 (95% CI: 0.63, 1.0). Conclusion The T2-FLAIR mismatch sign and scoring systems using standard clinical MRI predicted IDH and 1p/19q codeletion status in gliomas lacking contrast enhancement. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Badve and Hodges in this issue.

Hemorrhagic Transformation in Noncardioembolic Acute Ischemic Stroke: MRI Analysis From PACIFIC-STROKE.

In the phase 2 PACIFIC-STROKE trial (Proper Dosing and Safety of the Oral FXIa Inhibitor BAY 2433334 in Patients Following Acute Noncardioembolic Stroke), asundexian, an oral factor XIa inhibitor, did not increase the risk of hemorrhagic transformation (HT). In this secondary analysis, we aimed to investigate the frequency, types, and risk factors of HT on brain magnetic resonance imaging (MRI). This was a secondary analysis of the PACIFIC-STROKE trial. Patients with mild-to-moderate acute noncardioembolic ischemic stroke were randomly assigned to asundexian or placebo plus guideline-based antiplatelet therapy. Brain MRIs were required at baseline (≤120 hours after stroke onset) and at 26 weeks or end-of-study. HT was defined using the Heidelberg classification and classified as early HT (identified on baseline MRI) or late HT (new HT by 26 weeks) based on iron-sensitive sequences. Multivariable logistic regression models were used to test factors that are associated with early HT and late HT, respectively. Of 1745 patients with adequate baseline brain MRI (mean age, 67 years; mean National Institutes of Health Stroke Scale score, 2.8), early HT at baseline was detected in 497 (28.4%). Most were hemorrhagic infarctions (hemorrhagic infarction type 1: 15.2%; HI2: 12.7%) while a few were parenchymal hematomas (parenchymal hematoma type 1: 0.4%; parenchymal hematoma type 2: 0.2%). Early HT was more frequent with longer symptom onset-to-MRI interval. Male sex, diabetes, higher National Institutes of Health Stroke Scale large (>15 mm) infarct size, cortical involvement by infarct, higher number of acute infarcts, presence of chronic brain infarct, cerebral microbleed, and chronic cortical superficial siderosis were independently associated with early HT in the multivariable logistic regression model. Of 1507 with follow-up MRI, HT was seen in 642 (42.6%) overall, including 361 patients (23.9%) with late HT (new HT: 306; increased grade of baseline HT: 55). Higher National Institutes of Health Stroke Scale, large infarct size, cortical involvement of infarct, and higher number of acute infarcts predicted late HT. About 28% of patients with noncardioembolic stroke had early HT, and 24% had late HT detectable by MRI. Given the high frequency of HT on MRI, more research is needed on how it influences treatment decisions and outcomes.

The predictive value of MRI scores for neurodevelopmental outcome in infants with neonatal encephalopathy.

MRI scoring systems are utilized to quantify brain injury and predict outcome in infants with neonatal encephalopathy (NE). Our aim was to evaluate the predictive accuracy of total scores, white matter (WM) and grey matter (GM) subscores of Barkovich and Weeke scoring systems for neurodevelopmental outcome at 2 years of age in infants receiving therapeutic hypothermia for NE. Data of 162 infants were analyzed in this retrospective cohort study. DeLong tests were used to compare areas under the curve of corresponding items of the two scoring systems. LASSO logistic regression was carried out to evaluate the association between MRI scores and adverse composite (death or severe disabilities), motor and cognitive outcomes (Bayley developmental index <70). Weeke scores predicted each outcome measure with greater accuracy than the corresponding items of Barkovich system (DeLong tests p < 0.03). Total scores, GM and cerebellum involvement were associated with increased odds for adverse outcomes, in contrast to WM injury, after adjustment to 5' Apgar score, first postnatal lactate and aEEG normalization within 48 h. A more detailed scoring system had better predictive value for adverse outcome. GM injury graded on both scoring systems was an independent predictor of each outcome measure. A more detailed MRI scoring system had a better predictive value for motor, cognitive and composite outcomes. While hypoxic-ischemic brain injuries in the deep grey matter and cerebellum were predictive of adverse outcome, white matter injury including cortical involvement was not associated with any of the outcome measures at 2 years of age. Structured MRI evaluation based on validated scores may aid future clinical research, as well as inform parents and caregivers to optimize care beyond the neonatal period.