Temporal Lobe Lesions Research Articles

Toward a neuropsychology of political orientation: exploring ideology in patients with frontal and midbrain lesions.

How do people form their political beliefs? In an effort to address this question, we adopt a neuropsychological approach. In a natural experiment, we explored links between neuroanatomy and ideological preferences in two samples of brain lesion patients in New York City. Specifically, we compared the political orientations of patients with frontal lobe lesions, patients with amygdala lesions and healthy control subjects. Lesion type classification analyses revealed that people with frontal lesions held more conservative (or less liberal) beliefs than those with anterior temporal lobe lesions or no lesions. Additional analyses predicting ideology by extent of damage provided convergent evidence that greater damage in the dorsolateral prefrontal cortex-but not the amygdala-was associated with greater conservatism. These findings were robust to model specifications that adjusted for demographic, mood, and affect-related variables. Although measures of executive function failed to mediate the relationship between frontal lesions and ideology, our findings suggest that the prefrontal cortex may play a role in promoting the development of liberal ideology. Our approach suggests useful directions for future work to address the issue of whether biological developments precede political attitudes or vice versa-or both. This article is part of the theme issue 'The political brain: neurocognitive and computational mechanisms'.

Neural Underpinnings of Proactive Interference in Working Memory: Evidence From Patients With Unilateral Lesions.

Proactive interference in working memory refers to the fact that memory of past experiences can interfere with the ability to hold new information in working memory. The left inferior frontal gyrus (LIFG) has been proposed to play an important role in resolving proactive interference in working memory. However, the role of white matter pathways and other cortical regions has been less investigated. Here we investigated proactive interference in working memory using the Recent Probes Test (RPT) in 15 stroke patients with unilateral chronic lesions in left (n = 7) or right (n = 2) prefrontal cortex (PFC), or left temporal cortex (n = 6). We examined the impact of lesions in both gray and white matter regions on the size of the proactive interference effect. We found that patients with left PFC lesions performed worse overall, but the proactive interference effect in this patient group was comparable to that of patients with right PFC lesions, temporal lobe lesions, and controls. Interestingly, the size of the interference effect was significantly correlated with the degree of damage in the extreme/external capsule and marginally correlated with the degree of damage in the inferior frontal occipital fasciculus (IFOF). These findings suggests that ventral white matter pathways connecting the LIFG to left posterior regions play a role in resolving proactive interference in working memory. This effect was particularly evident in one patient with a very large interference effect (>3 SDs above controls) who had mostly spared LIFG, but virtually absent ventral white matter pathways (i.e., passing through the extreme/external capsules and IFOF). This case study further supports the idea that the role of the LIFG in resolving interference in working memory is dependent on connectivity with posterior regions via ventral white matter pathways.

Ventrolateral temporal lobectomy in normal dogs as a counterpart to human anterior temporal lobectomy: a preliminary study on the surgical procedure and complications.

Anterior temporal lobectomy (ATL) is a surgical procedure for drug-resistant mesial temporal lobe epilepsy that is commonly performed in human medicine. The purpose of this study was to determine whether ATL-like surgery, i.e., removal of the amygdala and hippocampal head, is possible in dogs, and to investigate its safety and postoperative complications. Eight healthy beagles underwent ATL-like surgery and were observed for 3 months postoperatively. Samples from the surgically resected tissues and postmortem brain were evaluated pathologically. The surgical survival rate was 62.5%. The major postoperative complications were visual impairment, temporal muscle atrophy on the operative side, and a postoperative acute symptomatic seizure. Due to the anatomical differences between dogs and humans, the surgically resected area to approach the medial temporal structures in dogs was the ventrolateral part of the temporal lobe. Therefore, the ATL-like surgery described in this study was named “ventrolateral temporal lobectomy” (VTL). This study is the first report of temporal lobectomy including amygdalohippocampectomy in veterinary medicine and demonstrates its feasibility. Although it requires some degree of skill, VTL could be a treatment option for canine drug-resistant epilepsy and lesions in the mesial temporal lobe.

Psychiatric manifestations in a case of viral limbic encephalitis.

Limbic encephalitis (LE), first described by Brierley et al. in 1960,[1] usually involving the medial temporal lobe, cingulate cortex, or hippocampus.[2] The clinical picture includes subacute recent onset of short-term memory loss, cognitive deficits,[3] confusion, seizures, autonomic disturbances, and sleep disturbances.[4] It is a rare cause of encephalitis and may or may not be associated with paraneoplastic cancers. The prognosis of the patient is better if the diagnosis is clinched early and prompt treatment is instituted.[1] Psychiatrists should keep the diagnosis of LE in mind when the patient presents with psychiatric manifestations along with seizures. A 60-year-old male, a known case of diabetes mellitus, hypertension, cerebrovascular accident, seizure disorder with poor drug compliance, and irregular follow-up presented with a history of multiple episodes of generalized tonic-clonic seizures within a span of 3 h. The patient had also developed vesicular lesions over the face on the right side, 3 days before onset of seizures. He was treated with injection levetiracetam 1000 mg for episodes of seizures in Emergency when the call was placed to the psychiatrist to rule out alcohol withdrawal. History revealed that the patient was a moderate drinker for the last 25 years and the last drink consumed was 3 days ago. The patient was asymptomatic till the onset of seizures. Mental status examination revealed an ill-kempt, agitated, restless, confused individual with cognitive deficit. The Glasgow Coma Score (GCS) of the patient deteriorated to5 (E2V1M2) and SPO2 levels fell to 80%. In view of low GCS, not maintaining oxygen saturation levels, the patient was intubated. Hematological investigations, biochemical parameters, serum electrolytes, liver function tests were unremarkable. Cerebrospinal fluid (CSF) analysis revealed lymphocytosis, raised protein, and globulin levels which was suggestive of viral etiology. Noncontrast enhanced computed tomography head showed cerebral edema and ill-defined hypodense lesions in the temporal region. Magnetic resonance imaging (MRI) [Figure 1] T2-weighted and fluid-attenuated inversion recovery revealed hyperintense lesions in medial temporal lobes and cingulate gyrus which were compatible with LE. Based on the suspected facial lesions, investigations suggesting viral etiology, and suboptimal response to treatment, the patient was started on injection acyclovir 600 mg intravenously thrice a day along with antiepileptic medications. The patient was taken off ventilator and sedation was stopped on 4th day. On reassessment, he was found to be aggressive and restless. Mental status examination revealed an ill-kempt, uncooperative individual with increased motor activity with agitation and aggressive behavior. Speech was incoherent, most of the time struggling at high pitch. The patient had fluctuating levels of consciousness and had memory loss. The clinical cognitive evaluation revealed attention to be arousable; however, concentration was ill-sustained. Following antiviral and antiepileptic medications, the patient's mental status improved over the next 2 weeks. However, he had less improvement in cognitive deficits. Over the following 2 weeks, overall gradual improvement was observed and the patient's behavior became less disorganized and became ambulatory.Figure 1: Magnetic resonance imaging showing hyperintense lesions in both medial temporal lobes compatible with limbic gyrusLE shows many symptoms ranging from delusions, confusion, hallucinations, aggression, irritability, memory impairment, and seizure disorders. The medial temporal lobe is the usual site of origin of seizures. It later develops into secondary generalized seizures which are resistive to most of the anti-epileptic drugs.[5] The triggering factors may be paraneoplastic tumors, viral infections, or immune checkpoint inhibitors There are multiple antibodies which are responsible for diverse symptoms present in the patients. Imaging and CSF analysis is required to rule out tumors and viral encephalitis respectively.[6] LE generally presents in individuals over the age of 45 years and gender depends on the type of antibody present.[6] Antibodies associated with LE are initiated by a peripheral immune response.[7] The diagnostic criteria for LE include various neuropsychiatric manifestations, findings of CSF suggestive of ongoing inflammation, and typical abnormality in radio-imaging. Diagnosis is often missed and probably underreported. MRI plays a pivotal role in establishing a diagnosis, where it shows hyper-intensive lesions, usually in the medial part of the temporal lobes. Prompt treatment should be initiated to prevent long-term sequela and to allow a speedy recovery. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given his consent for images and other clinical information to be reported in the journal. The guardian understands that names and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

A case report of Kluver–Bucy syndrome following herpes simplex encephalitis

Kluver–Bucy syndrome (KBS) is a rare syndrome seen after lesions of temporal lobes of the brain. Herpes simplex virus 1 is the most common infectious agent causing KBS owing to predilection of the virus to selectively affecting the temporal lobes. In this paper, we present a rare case of KBS that developed after herpes simplex encephalitis.

Lesion distribution and substrate of white matter damage in myotonic dystrophy type 1: Comparison with multiple sclerosis

Myotonic Dystrophy type 1 (DM1) is an autosomal dominant condition caused by expansion of the CTG triplet repeats within the myotonic dystrophy protein of the kinase (DMPK) gene. The central nervous system is involved in the disease, with multiple symptoms including cognitive impairment. A typical feature of DM1 is the presence of widespread white matter (WM) lesions, whose total volume is associated with CTG triplet expansion. The aim of this study was to characterize the distribution and pathological substrate of these lesions as well as the normal appearing WM (NAWM) using quantitative magnetization transfer (qMT) MRI, and comparing data from DM1 patients with those from patients with multiple sclerosis (MS). Twenty-eight patients with DM1, 29 patients with relapsing-remitting MS, and 15 healthy controls had an MRI scan, including conventional and qMT imaging. The average pool size ratio (F), a proxy of myelination, was computed within lesions and NAWM for every participant. The lesion masks were warped into MNI space and lesion probability maps were obtained for each patient group. The lesion distribution, total lesion load and the tissue-specific mean F were compared between groups. The supratentorial distribution of lesions was similar in the 2 patient groups, although mean lesion volume was higher in MS than DM1. DM1 presented higher prevalence of anterior temporal lobe lesions, but none in the cerebellum and brainstem. Significantly reduced F values were found within DM1 lesions, suggesting a loss of myelin density. While F was reduced in the NAWM of MS patients, it did not differ between DM1 and controls. Our results provide further evidence for a need to compare histology and imaging using new MRI techniques in DM1 patients, in order to further our understanding of the underlying disease process contributing to WM disease.

Comparison between Two Cases of Amnestic Anomia Caused by Left Temporal Lobe Lesion

Comparison between Two Cases of Amnestic Anomia Caused by Left Temporal Lobe Lesion

The role of MRI in the assessment of different causes of epilepsy

Background and aim Seizures are one of the most common medical problems affecting children, and epilepsy is the most common chronic neurological condition in children. The aim of this study was to highlight the different causes of epilepsy and to demonstrate and emphasize the usefulness of MRI epilepsy protocol on high-field magnet 3 T as imaging modality in the evaluation of pediatric epilepsy and its value in detecting subtle abnormalities that were commonly missed by previous nondedicated studies. Patients and methods This prospective study was conducted upon 40 pediatric patients diagnosed with epilepsy referred to a private center for MRI evaluation done on high-field magnet 3 T MRI, including the following sequences: three-dimensional T1 coronal (1 mm thick partition) with multi-planar reformat (MPR) on axial and sagittal, three-dimensional sagittal fluid attenuated inversion recovery (FLAIR) (1 or 1.5 mm thick, partition) with MPR on coronal and axial planes, high-resolution two-dimensional coronal T2‐weighted MRI, two-dimensional axial T2 (3 mm thickness), susceptibility weighted image (SWI) sequences (1.5 mm thick partition), and diffusion weighted image (DWI), as well as optional sequences, such as T1 MRI with gadolinium to look for contrast enhancement in the time interval between April 2018 and May 2020. Results The most common cause of epilepsy in our patients was malformation of the cortical development, accounting for 35% (14 patients), followed by neurocutaneous disorder and mesial temporal lobe lesions, each accounting for 25% (10 patients), followed by miscellaneous causes including brain tumors and vascular malformation [arterio-venous fistula (AVF), developmental venous anomaly (DVA), and cavernoma], accounting for 15% (six patients). Conclusion The dedicated MRI epilepsy protocol is a valuable tool in detection and illustration of the MR spectrum of different structural lesions causing pediatric seizures, describing the main MRI features of these disorders.

LGG-05. MOLECULAR GUIDED THERAPY FOR A PEDIATRIC LOW GRADE GLIOMA: A CASE REPORT

Low grade gliomas are the most common type of central nervous system tumors among children. Despite the fact that they are not typically life threatening, low grade gliomas remain a significant clinical challenge. Case Study: Patient is a 4-year-old male who presented at 20 months of age with several weeks of ataxia, emesis, and head tilt. Imaging revealed a right temporal lobe lesion; he was subsequently taken to surgery, where a gross total resection was achieved. Imaging 9 months post resection revealed recurrent disease within the right temporal region with leptomeningeal involvement. Four months later imaging revealed progression of multifocal disease and new growth within the sella. At this time the patient started standard treatment, Carboplatin and Vincristine, per CCG 9952A. Persistent slow progression was observed despite receiving standard therapy. The patient developed a grade 3 reaction to carboplatin, worsening with each subsequent dose. At this time, he was referred to our Precision Genomics Neuro Oncology program for tumor molecular characterization. Somatic tumor testing revealed an ETV6-NTRK3 fusion, at which time standard treatment was stopped, and patient began targeted therapy, Larotrectinib. Imaging was preformed 2 months post start of targeted therapy and revealed interval decrease in size of previously enhancing nodular lesions; findings consistent with treatment response. Disease burden continues to decrease with therapy. This case illustrates a clear benefit of using molecular guided therapy in low grade gliomas.

MBCL-38. UNUSUAL EXTRANEURAL METASTASIS OF PEDIATRIC EMBRYONAL TUMORS: TWO CASE REPORTS

We report two cases of unusual extraneural metastasis in patients with embryonal tumors without central nervous system disease progression and prolonged survival. The first patient presented at 16 years of age with atypical teratoid rhabdoid tumor of the cervical spine. The tumor was confirmed to have loss of INI1, SMARCB1 deletion of exons 1–3, and heterozygous deletion of 22q11.2. The patient received treatment initially per ACNS0333 with high dose chemotherapy and tandem autologous transplants. The patient developed a biopsy-confirmed liver metastasis six months from diagnosis and, subsequently, had disease progression including liver metastases, bony lesions, muscle involvement, and lung nodules. Two and a half years from diagnosis the patient has still not had a relapse in the CNS. The second patient presented with medulloblastoma isolated to the posterior fossa at 11 years of age and was treated on SJMB03 protocol with craniospinal irradiation and high dose chemotherapy. He had his first recurrence in the temporal lobe three years post treatment. He had multiple recurrences in the brain over the next five years treated with re-resections, adjuvant chemotherapy, and gamma knife radiotherapy. He then developed cervical lymphadenopathy, bony lesions, liver lesions, and lung nodules. Cervical lymph node biopsy confirmed medulloblastoma. Next generation sequencing from recurrent tumor showed somatic mutations in p53, KDM6A, and PPP2R1A. Fourteen years from treatment, he has now developed a temporal lobe lesion. These cases are notable for prolonged survival despite widely metastatic disease and genomics predicting poor prognosis as well as metastatic disease disproportionate to CNS disease.

Implicit-statistical learning in aphasia and its relation to lesion location

BackgroundImplicit-statistical learning (ISL) research investigates whether domain-general mechanisms are recruited in the linguistic processes that require manipulation of patterned regularities (e.g. syntax). Aphasia is a language disorder caused by focal brain damage in the left fronto-temporal-parietal network. Research shows that people with aphasia (PWA) with frontal lobe lesions manifest convergent deficits in syntax and ISL mechanisms. So far, ISL mechanisms in PWA with temporal or parietal lobe lesions have not been systematically investigated. AimsWe investigated two complementary hypotheses: 1) the anatomical hypothesis, that PWA with frontal lesions display more severely impaired ISL abilities than PWA with posterior lesions and 2) the behavioural hypothesis, that the magnitude of impairment in ISL mechanisms correlates to syntactic deficits in aphasia. MethodsWe tested 13 PWA, 5 with frontal lesions and 8 with posterior lesions, and 11 non-brain-damaged controls on a visual statistical learning (VSL) task. In addition, all PWA completed several linguistic tasks. Reaction times, obtained in the VSL task, were analyzed using linear mixed-effects model. Correlational statistics were used to assess the relationship between VSL task performance and linguistic measures. Results and DiscussionWe did not find support for the anatomical hypothesis as patients with spared frontal regions also manifested impaired ISL mechanisms. This is attributed to a) ISL mechanisms being vulnerable to other cognitive dysfunctions and/or b) ISL mechanisms anatomically extending to the posterior brain regions. Notably, ISL mechanisms were impaired, but not absent in aphasia. With regards to the behavioural hypothesis, we provide empirical evidence of correlation between ISL mechanisms and syntactic, but not lexical impairment in aphasia. We discuss both the theoretical contributions to the debate of domain-independence of ISL mechanisms and clinical implications for implicit language therapy.

Focal cortical dysplasia imaging discrepancies between MRI and FDG-PET: Unique association with temporal lobe location

PurposeAlthough magnetic resonance imaging (MRI) and 18F-2-fluorodeoxyglucose-positron emission tomography (FDG-PET) are used for pre-surgical assessment of focal cortical dysplasia (FCD), they often disagree. This study aimed to identify factors that contribute to discrepancies in FCD imaging between MRI and FDG-PET. MethodsSixty-two patients (mean age, 18.9 years) with a FCD type I or II were retrospectively selected. These patients were visually categorized into two groups: 1) extent of PET abnormality larger than MRI abnormality and 2) vice versa or equivalent. Predictive factors of these two groups were analyzed by multivariate logistic regression. The extent of hypometabolic transient zone surrounding FCDs and their mean standardized uptake values were measured and compared by the Mann–Whitney U-test. ResultsFCDs were detected on MRI and PET in 46 and 55 patients, respectively, whereas no abnormality was detected in 4 patients. The PET hypometabolic areas were larger than the MRI abnormal areas in 26 patients (88 % in the temporal lobe), whereas the PET hypometabolic areas were equivalent or smaller than the MRI abnormal areas in 32 patients (69 % in the frontal lobe). The temporal lobe location was an independent predictor for differentiating the two groups (OR = 35.2, 95 % CI = 6.81–168.0, P < .001). The temporal lobe lesions had significantly wider transient zones and lower standardized uptake values than those in the other lobes (P < .001, both). ConclusionThe discrepancies between MRI and FDG-PET findings of FCD were associated with temporal lobe location.

Expanded Clinical Phenotype, Oncological Associations, and Immunopathologic Insights of Paraneoplastic Kelch-like Protein-11 Encephalitis

Recognizing the presenting and immunopathological features of Kelch-like protein-11 immunoglobulin G seropositive (KLHL11 IgG+) patients may aid in early diagnosis and management. To describe expanding neurologic phenotype, cancer associations, outcomes, and immunopathologic features of KLHL11 encephalitis. This retrospective tertiary care center study, conducted from October 15, 1998, to November 1, 2019, prospectively identified 31 KLHL11 IgG+ cases in the neuroimmunology laboratory. Eight were identified by retrospective testing of patients with rhomboencephalitis (confirmed by tissue-based-immunofluorescence and transfected-cell-based assays). Outcome variables included modified Rankin score and gait aid use. All 39 KLHL11 IgG+ patients were men (median age, 46 years; range, 28-73 years). Initial clinical presentations were ataxia (n = 32; 82%), diplopia (n = 22; 56%), vertigo (n = 21; 54%), hearing loss (n = 15; 39%), tinnitus (n = 14; 36%), dysarthria (n = 11; 28%), and seizures (n = 9; 23%). Atypical neurologic presentations included neuropsychiatric dysfunction, myeloneuropathy, and cervical amyotrophy. Hearing loss or tinnitus preceded other neurologic deficits by 1 to 8 months in 10 patients (26%). Among patients screened for malignancy (n = 36), testicular germ-cell tumors (n = 23; 64%) or testicular microlithiasis and fibrosis concerning for regressed germ cell tumor (n = 7; 19%) were found in 83% of the patients (n = 30). In 2 patients, lymph node biopsy diagnosed metastatic lung adenocarcinoma in one and chronic lymphocytic leukemia in the other. Initial brain magnetic resonance imaging revealed T2 hyperintensities in the temporal lobe (n = 12), cerebellum (n = 9), brainstem (n = 3), or diencephalon (n = 3). Among KLHL11 IgG+ patients who underwent HLA class I and class II genotyping (n = 10), most were found to have HLA-DQB1*02:01 (n = 7; 70%) and HLA-DRB1*03:01 (n = 6; 60%) associations. A biopsied gadolinium-enhancing temporal lobe lesion demonstrated T cell-predominant inflammation and nonnecrotizing granulomas. Cerebellar biopsy (patient with chronic ataxia) and 2 autopsied brains demonstrated Purkinje neuronal loss and Bergmann gliosis, supporting early active inflammation and later extensive neuronal loss. Compared with nonautoimmune control peripheral blood mononuclear cells, cluster of differentiation (CD) 8+ and CD4+ T cells were significantly activated when patient peripheral blood mononuclear cells were cultured with KLHL11 protein. Most patients (58%) benefitted from immunotherapy and/or cancer treatment (neurological disability stabilized [n = 10] or improved [n = 9]). Kaplan-Meier curve demonstrated significantly higher probability of wheelchair dependence among patients without detectable testicular cancer. Long-term outcomes in KLHL11-IgG+ patients were similar to Ma2 encephalitis. Kelch-like protein-11 IgG is a biomarker of testicular germ-cell tumor and paraneoplastic neurologic syndrome, often refractory to treatment. Described expanded neurologic phenotype and paraclinical findings may aid in its early diagnosis and treatment.

The congruence of interoceptive predictions and hippocampal-related memory

Interoceptive deficits are associated with medial temporal lobe (MTL) lesions, and especially the hippocampus, which may relate to interoception's reliance upon predictive coding and hence on mnemonic processes. Here, we develop a new task to assess interoceptive predictions and assess their dependence upon MTL memory systems. Healthy participants were asked to imagine and predict what they would feel like across nine interoceptive situations. Later, each situation was physically experienced, and participants reported what they actually felt. An index of predictive congruence was derived and correlated with a neuropsychological measure of hippocampal dependent learning and memory (HDLM), finding that more accurate predictions were associated with better HDLM (Cohen's d = 0.5). We suggest the MTL, and in particular the hippocampus, generates contextually appropriate episodic memories, providing a predictive framework for interpreting afferent bodily neurohormonal signals. The loss of this capacity may account for the profound interoceptive deficits observed following MTL lesions.

Clinical characteristics and outcome of patients with autoimmune encephalitis: clues for paraneoplastic aetiology.

Autoimmune encephalitis (AE) represents a complex syndrome with diverse clinical manifestations and therapeutic outcomes. The aim of this study was to report the clinical characteristics and the long-term outcome of patients with paraneoplastic and idiopathic AE. All patients with subacute encephalopathy admitted to the Neurology Department of our Institution from January 2012 to May 2019 were consecutively enrolled. Patients' serum and cerebrospinal fluid were tested for neural-specific autoantibodies by indirect immunofluorescence assays on mouse brain, rat neurons, cell-based assays and immunoblots. Outcome was assessed by the modified Rankin Scale score. From 107 adult patients with subacute encephalopathy, 50 patients were finally diagnosed with AE. Neural antibodies (Abs) were detected in 45/50 patients (90%). Leucine-rich glioma-inactivated protein 1 immunoglobulin G was the most frequent (6/50, 12%) Ab specific to neural surface antigens detected in adults with AE. Paraneoplastic encephalitis was diagnosed in 16/50 patients (32%). The presence of bilateral temporal lobe lesions on magnetic resonance imaging and cerebrospinal fluid restricted oligoclonal bands was associated with a higher probability to detect cancer at the time of AE diagnosis. All patients with Abs to neural surface antigens had a good outcome at last follow-up. Severe disability at AE onset and the lack of long-term immunosuppression predicted a poor outcome. Leucine-rich glioma-inactivated protein 1 immunoglobulin G was the most frequent Ab detected. Patients with bilateral temporal lobe lesions and oligoclonal bands have a higher probability to harbour an occult tumour. In these patients, a strict surveillance and monitoring for cancer detection is recommended.

Clinical characteristics, treatment and prognosis of angiocentric glioma.

Angiocentric glioma (AG) is a rare subtype of neuroepithelial tumor in children and young adults that commonly presents with seizures. To study the clinical characteristics, treatment and prognosis of patients with AG, the features of two cases of AG were described and 108 cases reported in the literature were assessed. The cases of the present study were two males aged 8 and 16 years, who mainly presented with seizures. MRI revealed superficial, non-enhanced lesions in the left temporal and right frontal lobe, respectively. The two patients underwent gross total resection (GTR) and remained seizure-free without neurological deficits after 3.5 and 2.5 years, respectively. Histopathological examination revealed that the tumors consisted of monomorphous cells that surrounded the blood vessels and neurons in the cerebral cortex, and formed concentric sleeves or pseudorosettes. Furthermore, immunostaining indicated that the diffuse infiltrative neoplastic cells were positive for glial fibrillary acidic protein and a dot-like pattern of epithelial membrane antigen was observed. AG mostly appeared similar to low-grade gliomas on MRI. GTR of the lesions was curative and radiation or chemotherapy were not required. AG typically has a favorable prognosis, with low mortality and incidence of disability.

DWI scoring system for prognosis of acute encephalopathy with biphasic seizures and late reduced diffusion

The aim of this study was to predict neurological outcomes for acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) using diffusion-weighted imaging (DWI), and assess relationships between anatomical sites of lesions and their outcomes. We assessed DWI abnormalities and neurological outcomes in 30 patients with AESD, and classified patients into severe and non-severe groups according to their neurological outcomes. We also established a DWI scoring system as follows: zero for normal, and one for lesion at each location. Differences between the severe and non-severe groups were examined, and receiver operating characteristic (ROC) curve analysis was performed. Nine (30%) patients were classified into the severe group. On DWI, patients in the severe group were more likely to have temporal lobe (P = 0.014), perirolandic (P = 0.008), and corpus callosum (P = 0.0008) lesions than those in the non-severe group. The total DWI scores were significantly higher in the severe group than those in the non-severe group (P = 0.0002). ROC curve showed an area under the curve of 0.929, with a cutoff value of five, sensitivity of 88.9%, and specificity of 81.0%. Patients with severe AESD had more extensive DWI abnormalities than those with non-severe AESD. Our DWI scoring system may be useful for the prediction of outcomes of AESD. Widespread lesions seemed to have stronger influence on outcomes than each lesion location.

Abstract WP368: Evaluation of Brain Regional Characteristics Related With Post-Stroke Delirium Using Machine Learning and Statistical Analysis

Background: The present study was performed to evaluate the brain regional characteristics related with development of post-stroke delirium using the machine learning and statistical analysis. Method: We used clinical and radiological data prospectively collected from 675 acute ischemic stroke patients, who were admitted in stroke unit from August 2017 to July 2018. Delirium occurrence in the patients was screened with Confusion Assessment Method and finally diagnosed using the criteria of the Diagnostic and Statistical Manual of Mental Disorders (fifth edition). Three machine learning models, Support Vector Machine (SVM), Random Forest (RF) and Tree-based Gradient Boosting (XGBoost), were applied for the prediction of post-stroke delirium with the clinical and radiologic data. And logistic regression analysis was performed to evaluate the significance of the brain regional parameters included in the importance features which were obtained from the XGBoost result. Results: Post-stroke delirium occurred in 66 (9.8%) of the total patients. On the comparison of the test accuracy to predict delirium occurrence, RF (94%), XGBoost test (93%), and SVM (89%) showed similar prediction rates. Of the brain regional parameters included in the top 30 feature importance, right side cerebral hemisphere, non-lacunar infarction, severity of periventricular white matter changes, acute temporal lobe lesion, cerebellum, brain stem, and previous lesions developed on right side cerebral hemisphere, and in temporal or frontal lobe. Conclusion: The present study shows that the brain regional characteristics related with the post-stroke delirium are shown to be significant when controlling the other features using statistical analysis with machine learning. Even though we need more studies to validate the relationships between post-stroke delirium and brain regional characteristics, the present brain regional characteristics could provide significant evidences to predict post-stroke delirium for the acute ischemic stroke patients.

5-ALA fluorescence in a WHO grade I papillary glioneuronal tumour: a case report

5-ALA is proven to be effective in high-grade glioma operative resection. The use of 5-ALA in WHO grade I lesions is still controversial. A 49-year-old lady was diagnosed in 2004 with a left temporal lobe lesion as an incidental finding; she was followed up clinically and radiologically. In 2016, the lesion showed contrast enhancement and she was offered surgical resection but given she is asymptomatic, she refused. In 2018, the lesion showed signs of transformation with ring contrast enhancement, increased vasogenic oedema and perfusion; the patient accepted surgery at that point. She had preoperative mapping by navigated transcranial magnetic stimulation and she had operative resection with 5-ALA. The tumour was bright fluorescent under Blue 400 filter—Zeiss Pentero 900©(Carl Zeiss Meditec)—and both bright fluorescence and pale fluorescence were resected. Postoperative MRI showed complete resection and histopathology revealed WHO grade I papillary glioneuronal tumour, negative for BRAF V600 mutation. WHO grade I papillary glioneuronal tumour may present as 5-ALA fluorescent lesions. From a clinical perspective, 5-ALA can be used to achieve complete resections in these lesions which, in most cases, can be curative.

Discrepancies in Hearing Thresholds between Pure-Tone Audiometry and Auditory Steady-State Response in Non-Malingerers.

To evaluate discrepancies between pure-tone audiometry (PTA) and auditory steady state response (ASSR) tests in non-malingerers and investigate brain lesions that may explain the discrepancies, especially in cases where the PTA threshold was worse than the estimated ASSR threshold. PTA, speech audiometry, auditory brainstem response, ASSR, and neuroimaging tests were carried out on individuals selected from 995 cases of hearing impairment. Among these, medical records of 25 subjects (19 males, 6 females; mean age = 46.5 ± 16.0 years) with significant discrepancy between PTA and estimated ASSR thresholds were analyzed retrospectively. To define acceptable levels of discrepancy in PTA and ASSR hearing thresholds, 56 patients (27 males, 29 females; mean age = 53.0 ± 13.6 years) were selected for the control group. Magnetic resonance images, magnetic resonance angiograms, and positron emission tomograms were reviewed to identify any neurologic abnormalities. Pathologic brain lesions were found in 20 cases (80%) in the study group, all of which showed a significant discrepancy in hearing threshold between PTA and ASSR. Temporal lobe lesions were found in 14 cases (70%), frontal lobe lesions in 12 (60%), and thalamic lesions without the frontal or temporal lobe in 2 cases (10%). On repeated PTA and ASSR tests a few months later, the discrepancy between ASSR and behavioral hearing thresholds was reduced or resolved in 6 cases (85.7%). Temporal lobe lesions were found in all 3 cases in which the estimated ASSR threshold worsened with unchanged PTA threshold, and frontal lobe lesions were found in all 3 cases in which the PTA threshold improved but the estimated ASSR threshold was unchanged. No neurological lesions were found in 5 cases (20%) of patients with a discrepancy between ASSR and behavioral hearing thresholds. Clinicians should not rely exclusively on ASSR, especially in cases of central nervous system including temporal, frontal lobe, or thalamus lesions. If no lesions are found in a neuroimaging study of a patient with a discrepancy between PTA thresholds and estimated ASSR thresholds, further functional studies of the brain may be needed. If clinicians encounter patients with a discrepancy between PTA thresholds and estimated ASSR thresholds, an evaluation of brain lesions and repeat audiologic tests are recommended in lieu of relying solely on ASSR.