Underwent MRI Scans Research Articles

Brain volumetric changes in the general population following the COVID-19 outbreak and lockdown

The coronavirus disease 2019 (COVID-19) outbreak introduced unprecedented health-risks, as well as pressure on the economy, society, and psychological well-being due to the response to the outbreak. In a preregistered study, we hypothesized that the intense experience of the outbreak potentially induced stress-related brain modifications in the healthy population, not infected with the virus. We examined volumetric changes in 50 participants who underwent MRI scans before and after the COVID-19 outbreak and lockdown in Israel. Their scans were compared with those of 50 control participants who were scanned twice prior to the pandemic. Following COVID-19 outbreak and lockdown, the test group participants uniquely showed volumetric increases in bilateral amygdalae, putamen, and the anterior temporal cortices. Changes in the amygdalae diminished as time elapsed from lockdown relief, suggesting that the intense experience associated with the pandemic induced transient volumetric changes in brain regions commonly associated with stress and anxiety. The current work utilizes a rare opportunity for real-life natural experiment, showing evidence for brain plasticity following the COVID-19 global pandemic. These findings have broad implications, relevant both for the scientific community as well as the general public.

Deep Learning for Differentiating Benign From Malignant Parotid Lesions on MR Images.

Purpose/Objectives(s)Salivary gland tumors are a rare, histologically heterogeneous group of tumors. The distinction between malignant and benign tumors of the parotid gland is clinically important. This study aims to develop and evaluate a deep-learning network for diagnosing parotid gland tumors via the deep learning of MR images.Materials/MethodsTwo hundred thirty-three patients with parotid gland tumors were enrolled in this study. Histology results were available for all tumors. All patients underwent MRI scans, including T1-weighted, CE-T1-weighted and T2-weighted imaging series. The parotid glands and tumors were segmented on all three MR image series by a radiologist with 10 years of clinical experience. A total of 3791 parotid gland region images were cropped from the MR images. A label (pleomorphic adenoma and Warthin tumor, malignant tumor or free of tumor), which was based on histology results, was assigned to each image. To train the deep-learning model, these data were randomly divided into a training dataset (90%, comprising 3035 MR images from 212 patients: 714 pleomorphic adenoma images, 558 Warthin tumor images, 861 malignant tumor images, and 902 images free of tumor) and a validation dataset (10%, comprising 275 images from 21 patients: 57 pleomorphic adenoma images, 36 Warthin tumor images, 93 malignant tumor images, and 89 images free of tumor). A modified ResNet model was developed to classify these images. The input images were resized to 224x224 pixels, including four channels (T1-weighted tumor images only, T2-weighted tumor images only, CE-T1-weighted tumor images only and parotid gland images). Random image flipping and contrast adjustment were used for data enhancement. The model was trained for 1200 epochs with a learning rate of 1e-6, and the Adam optimizer was implemented. It took approximately 2 hours to complete the whole training procedure. The whole program was developed with PyTorch (version 1.2).ResultsThe model accuracy with the training dataset was 92.94% (95% CI [0.91, 0.93]). The micro-AUC was 0.98. The experimental results showed that the accuracy of the final algorithm in the diagnosis and staging of parotid cancer was 82.18% (95% CI [0.77, 0.86]). The micro-AUC was 0.93.ConclusionThe proposed model may be used to assist clinicians in the diagnosis of parotid tumors. However, future larger-scale multicenter studies are required for full validation.

Quantitative Bone Marrow MRI in Children with Acute Lymphoblastic Leukemia

The aim of this study was to evaluate, using MRI, the changes in bone marrow fat fraction (BMFF) of patients with acute lymphoblastic leukemia (ALL), in comparison with children without hematological disorders. Methods and Results: The cohort of the study subjects included 20 patients aged between 5 and 17 years (mean age of 11.2±3.6 years; 10 boys and 10 girls) with clinically and morphologically confirmed diagnosis of ALL All patients underwent MRI scanning in the acute phase of the disease before the start of specific therapy. Then, the study was repeated in 10 patients (mean age of 12.2±2.3 years; 8 boys and 2 girls) during treatment, according to the ALL-MB 2015 protocol for patients with primary ALL and according to the ALL-REZ-MB 2016 protocol for patients with relapsed ALL. The control group consisted of 24 healthy controls of the same age group (mean age of 12±2.8; 17 boys and 7 girls) with no prior hematologic diseases. MRI scanning was carried out using a Philips Achieva dStream 3T scanner with a 32-channel FlexCoverage abdominal receiving coil. The MRI protocol included images obtained with the mDIXON Quant technique in the coronal plane, completely covering the pelvic bones and lumbar spine. Fat fraction (FF) maps were generated automatically on the MRI console using the 7-peak fat model and were corrected for T2* effects. Regions of interest (ROI) measuring 150 mm2 were placed in the bodies of the left and right iliac bones (Ilium L, Ilium R) as well as in the L4 and L5 vertebral bodies, taking care to avoid blood vessels, cortical bones and areas that could potentially contain artifacts. In the group of healthy controls, BMFF value was 51%±11% in the bodies of the iliac bones and 32%±10% in the lumbar vertebrae. In the group of patients with the acute phase of the disease, BMFF was as low as 3.1%±2.6% in all the bone structures. In patients who had undergone chemotherapy, the mean BMFF increased up to 77%±7% in the iliac bones and up to 65%±13% in the vertebrae. Student's t-test for dependent samples revealed a statistically significant increase in the mean BMFF values in all the bone structures after chemotherapy (P<0.01). After specific therapy, BMFF was also significantly higher than under normal conditions (P<0.01). Conclusion: This study provides important diagnostic information for various phases of ALL treatment, especially in suspected cases of resistant or recurrent disease.

Cognitive Function and White Matter Lesions in Medication-Overuse Headache.

PurposeThis study was designed to investigate the cognitive function and the white matter lesions (WMLs) and the relationship between them in medication-overuse headache (MOH) patients.MethodsSubjects were enrolled and performed Montreal Cognitive Assessment (MoCA, Chinese-Beijing Version), Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD-24), and Pittsburgh Sleep Quality Index (PSQI) to evaluate the general cognitive function, anxiety, depression and sleep quality, and they were divided into three groups according to the MoCA scores: healthy controls, MOH with normal cognition group and MOH with cognitive impairment group. All the participants underwent MRI scans and images were obtained for WML evaluation with Fazekas scale.ResultsOne hundred thirty-four participants were enrolled into this study, 46 of them for healthy controls, and 88 for MOH patients, 40 of the MOH patients for MOH with cognitive impairment group, and 48 for MOH with normal cognition group. MOH patients had significantly lower MoCA scores, including the scores of visuospatial and executive function, attention, and orientation, while they had significantly greater HAMA scores, HAMD-24 scores, PSQI scores, and deep white matter hyperintensity scores compared to healthy controls. And in MOH patients, the age, disease duration, monthly headache days, and periventricular white matter hyperintensity scores in patients with cognitive impairment were greater than those in patients with normal cognition. Moreover, the MoCA scores were negatively related to age, disease duration, monthly headache days, and Fazekas scale scores, and disease duration and monthly headache days were significant predictors of cognitive impairment in MOH patients.ConclusionMOH patients showed cognitive impairment and increased WML burden. And in MOH patients, cognitive function was negatively related to WML burden, and disease duration and monthly headache days were potential predictors of cognitive impairment. Prompt and effective treatment to stop the progression of the disease may alleviate cognitive impairment in MOH patients.

A Multimodal Imaging Approach Demonstrates Reduced Midbrain Functional Network Connectivity Is Associated With Freezing of Gait in Parkinson's Disease.

Background: The pathophysiological mechanisms underlying freezing of gait (FOG) are poorly defined. MRI studies in FOG showed a distinct pattern of cortical atrophy and decreased functional connectivity (FC) within motor and cognitive networks. Furthermore, reduced rs-FC within midbrain, frontal, and temporal areas has been also described. This study investigated the patterns of whole-brain FC alterations within midbrain inter-connected regions in PD-FOG patients, and whether these patterns are linked to midbrain structural damage using a multi-modal imaging approach, combing structural and functional imaging techniques.Methods: Thirty three PD patients (16 PD-FOG, 17 PD noFOG), and 21 sex- and age-matched healthy controls (HCs) were prospectively enrolled. All subjects underwent MRI scan at 1.5T, whereas only PD patients underwent clinical and cognitive assessment. Grey matter (GM) integrity was measured using voxel-based morphometry (VBM). VBM findings served as basis to localize midbrain damage, and were further used as a seed region for investigating whole-brain FC alterations using rs-fMRI.Results: In rs-fMRI, patients with PD and FOG demonstrated significant decrease of midbrain-cortical FC levels in the R PCG, right postcentral, and supramarginal gyri compared to controls and the middle cingulate compared to noFOG group. Based on the regression analysis, MOCA, UPDRS-III total score, and FOG severity scores were associated with FC levels in several frontal, parietal and temporal regions.Discussion: The present results suggest that midbrain structural damage as well as decreased FC within the brainstem functional network might contribute to FOG occurrence in PD patients.

Structural Gray and White Matter Correlates of Awareness in Alzheimer's Disease.

Unawareness of disease is a common feature of Alzheimer's disease (AD), but few studies explored its neural correlates. Additionally, neural correlates according to the object of awareness are unexplored. To investigate structural brain correlates in relation to different objects of awareness. 27 people with AD underwent MRI scanning on a 3T Siemens Prisma. T1-MPRAGE was used to investigate cortical thickness and white matter microstructure was defined by DTI as fractional anisotropy, mean, axial, and radial diffusivity. Preprocessing used FreeSurfer6.0, ExploreDTI, and FSL-TBSS. Awareness of disease, cognitive deficits, emotional state, relationships, and functional capacity were assessed with the short version of the Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia. Voxel-wise correlations between brain structure and awareness were determined by FSL-PALM. Analyses were corrected for multiple comparisons using Threshold Free Cluster Enhancement and FWE. Lower left hemisphere cortical thickness was related to poorer disease awareness uncorrected and corrected for age, sex, and MMSE. In the uncorrected model, mainly right-sided, but also left temporal lower cortical thickness was related to decreased awareness of cognitive deficits. Correcting for age, sex, and MMSE eliminated correlations for the right hemisphere, but extensive correlations in the left hemisphere remained. For white matter integrity, higher right hemisphere MD was related to lower cognitive awareness deficits, and lower FA was related to lower functional capacity awareness. Findings suggest that extensive regions of the brain are linked to self-awareness, with particular frontal and temporal alterations leading to unawareness, in agreement with theoretical models indicating executive and mnemonic forms of anosognosia in AD.

Cortical diffusion kurtosis imaging and thalamic volume are associated with cognitive and walking performance in relapsing-remitting multiple sclerosis.

In multiple sclerosis (MS), pronounced neurodegeneration manifests itself as cerebral gray matter (GM) atrophy, which is associated with cognitive and physical impairments. Microstructural changes in GM estimated by diffusion kurtosis imaging (DKI) may reveal neurodegeneration that is undetectable by conventional structural MRI and thus serve as a more sensitive marker of disease progression. The primary objective was to investigate the relationships between morphological and diffusional properties in cerebral GM and physical and cognitive performance in relapsing-remitting MS (RRMS) patients. A secondary objective was to investigate the relationship between GM microstructure and white matter (WM) injury, estimated by the volume of WM lesions. Sixty-seven RRMS patients performed the brief repeatable battery of neuropsychological tests (BRB-N), the 6-minute walk test (6MWT), the six spot step test (SSST), and underwent MRI scans using structural and DKI protocols. GM volumetrics and DKI measurements were analyzed in the cortex and deep GM structures using a general linear model with demographics, physical- and cognitive performance as covariates. Mean diffusivity (MD) in the cortex was associated with the SSST, 6MWT, information processing, global cognitive performance, and volume of WM lesions. In addition, thalamic volume was associated with SSST (r2 = 0.21, 6MWT (r2 = 0.18), information processing (r2 = 0.21), and WM lesion volume (r2 = 0.60). Cortical diffusion and thalamic volume are associated with walking and cognitive performance in RRMS patients and are highly affected by the presence of WM lesions.

Response to targeted cognitive training may be neuroprotective in patients with early schizophrenia

Individuals with schizophrenia exhibit widespread cortical thinning associated with illness severity and deficits in cognition. However, intact cortical thickness (CTh) may serve as a protective factor. The current study sought to examine changes in CTh in response to auditory targeted cognitive training (TCT) in individuals with recent onset schizophrenia. Participants underwent MRI scanning and a cognitive assessment before and after being randomly assigned to 40 h of either TCT (N = 21) or a computer games control condition (CG; N = 22) over 16 weeks. Groups did not differ at baseline on demographic variables or measures of CTh. At the level of group averages, neither group showed significant pre-post changes in CTh in any brain region. However, changes in CTh related to individual differences in treatment outcome, as improved global cognition in the TCT group corresponded to reduced cortical thinning in frontal, temporal, parietal, and occipital lobes. These relationships were not observed in the CG group. The current findings suggest that TCT may be neuroprotective in early schizophrenia, such that individuals who improved in response to training also showed a reduction in cortical thinning that may be otherwise hastened due to age and illness.

Increased peripheral inflammation in schizophrenia is associated with worse cognitive performance and related cortical thickness reductions.

While the biological substrates of brain and behavioural changes in persons with schizophrenia remain unclear, increasing evidence implicates that inflammation is involved. In schizophrenia, including first-episode psychosis and anti-psychotic naïve patients, there are numerous reports of increased peripheral inflammation, cognitive deficits and neuropathologies such as cortical thinning. Research defining the relationship between inflammation and schizophrenia symptomatology and neuropathology is needed. Therefore, we analysed the level of C-reactive protein (CRP), a peripheral inflammation marker, and its relationship with cognitive functioning in a cohort of 644 controls and 499 schizophrenia patients. In a subset of individuals who underwent MRI scanning (99 controls and 194 schizophrenia cases), we tested if serum CRP was associated with cortical thickness. CRP was significantly increased in schizophrenia patients compared to controls, co-varying for age, sex, overweight/obesity and diabetes (p < 0.006E-10). In schizophrenia, increased CRP was mildly associated with worse performance in attention, controlling for age, sex and education (R =-0.15, p = 0.001). Further, increased CRP was associated with reduced cortical thickness in three regions related to attention: the caudal middle frontal, the pars opercularis and the posterior cingulate cortices, which remained significant after controlling for multiple comparisons (all p < 0.05). Together, these findings indicate that increased peripheral inflammation is associated with deficits in cognitive function and brain structure in schizophrenia, especially reduced attention and reduced cortical thickness in associated brain regions. Using CRP as a biomarker of peripheral inflammation in persons with schizophrenia may help to identify vulnerable patients and those that may benefit from adjunctive anti-inflammatory treatments.

Functional connectivity patterns of the subgenual anterior cingulate cortex in first-episode refractory major depressive disorder.

Although accumulating evidence has been elucidating the neuronal basis of refractory/nonrefractory major depressive disorder (rMDD/nrMDD), the results are inconsistent, and little is known about the distinct neural mechanisms underlying rMDD. Here, we explored the convergent/divergent brain networks between first-episode MDD subtypes using the resting-state functional connectivity (RSFC) approach. In total, 33 healthy controls (HCs), 31 first-episode rMDD patients and 33 first-episode nrMDD patients were enrolled and underwent MRI scanning. The left subgenual anterior cingulate cortex (sgACC) was selected as the seed region, and RSFC was employed to evaluate associations between the seed and other regions in the whole brain. Both MDD subtypes exhibited convergent left sgACC-based neural networks, including increased RSFC with the dorsal prefrontal cortex (DPFC) and decreased RSFC with the bilateral orbitofrontal cortex (OFC) and right parahippocampus. rMDD patients exhibited increased left sgACC-OFC RSFC relative to nrMDD patients, and RSFC with the bilateral OFC in rMDD patients was negatively correlated with HAMD scores. These findings confirmed our speculation that convergent and divergent neural networks exist between rMDD and nrMDD. Cortical-limbic circuits, especially the prefrontal-limbic circuit, may serve as the convergent dysfunctional neural circuitry in MDD subtypes. As an important biomarker, a unique OFC-sgACC circuit abnormality was identified in rMDD patients, which might help elucidate the underlying mechanism regarding treatment responses in rMDD patients.

Functional abnormalities of striatum are related to the season-specific effect on schizophrenia.

Schizophrenia is a syndrome that is typically accompanied by delusions, hallucinations and cognitive impairments. Specifically, abundant evidences support the notion that more people diagnosed with schizophrenia are born during fall-winter than spring-summer. Although pathophysiological of schizophrenia might be associated with abnormal brain functional network, little is currently known the relationship between season and deficient brain functional network of schizophrenia. To investigate this issue, in this study 51 schizophrenic subjects and 72 healthy controls underwent MRI scanning to detect the brain functional mapping, each at spring-summer and fall-winter season throughout the year. The data-driven method was used to measure the blood oxygen metabolism variability (BOMV). Decreased BOMV in spring-summer while increased in fall-winter were observed within dopaminergic network of schizophrenic subjects, including striatum, thalamus, and hippocampus. The post hoc analysis exploring the coupling among changed BOMV regions, confirmed that a positive relationship, between pallidum and hippocampus existed in fall-winter healthy controls, but not in fall-winter schizophrenic subjects. These findings identified that seasonal effect on striatum might be associated with modulation of striatum-hippocampus. Our results provide a new insight into the role of season in understanding the pathophysiological of schizophrenia.

Clinical presentation, MRI and clinical outcome scores do not accurately predict an important meniscal tear in a symptomatic discoid meniscus.

Discoid menisci can be symptomatic from instability or a tear. A torn discoid meniscus is likely to require repair to preserve meniscal function and should not be missed. This is the first study to evaluate a range of pre-operative methods to predict the likelihood of a torn discoid meniscus. A retrospective analysis of prospectively collected data was performed. Clinical, radiographic and operative data were reviewed. Patients were grouped based on the presence of a tear or not during surgery. All patients underwent MRI scans pre-operatively which were validated with arthroscopy findings to calculate sensitivity. All patients completed Pedi-KOOS and Pedi-IKDC pre-operative scores. There were 32 discoid menisci in 27 patients. Mean age at surgery was 10.4years (6-16). Nineteen patients were female. Seventeen menisci were identified as torn at time of arthroscopy (53%), 15 were unstable but not torn. Clinical findings did not differentiate between the torn or unstable menisci. MRI was only 75% sensitive and 50% specific at identifying a torn discoid meniscus. There was no statistical difference between KOOS-child (n.s.) and Pedi-IKDC (n.s.) scores between the groups. MRI is neither sensitive nor specific at identifying tears in discoid menisci. There is no difference in pre-operative outcome scores for patients with a torn or unstable discoid meniscus; pre-operative PROMs are a poor predictor of a meniscal tear. This study emphasises that pre-operative tests and clinical findings are not conclusive for identifying a meniscal tear and the operating surgeon should be vigilant in identifying and repairing tears at the time of surgery. Pre-operative findings poorly correlate to arthroscopic findings and potential surgical interventions required. Patients and parents/carers should, therefore, be appropriately counselled prior to surgery that post-operative measures are dependent on intra-operative findings and not pre-operative findings in patients. III.

Sustained and transient gray matter volume changes after n-back training: A VBM study

Working memory training causes functional adaptations in the brain, which include changes in activation and functional connectivity that remain stable over time. Few studies have investigated gray matter (GM) changes after working memory training, and they have produced heterogeneous results without clarifying the stable effects of training. The present study was designed to test for sustained and transient anatomic changes after only 200 min of working memory training. The voxel-based morphometry technique was used in order to investigate the GM changes produced by a brief single n-back training, immediately and 5 weeks after finishing it. The sample was composed by 59 human participants who underwent MRI scanning and were assigned to either a training group or a passive control group. Results showed sustained GM volume enlargement in the right superior parietal cortex and a transient GM decrease in the right putamen. The brain adaptation in the right superior parietal cortex was stronger in individuals who showed greater improvements in performance. The results provide further evidence that a brief working memory training is able to produce brain plasticity in structures related to the trained task.

Neonatal brain metabolite concentrations: Associations with age, sex, and developmental outcomes.

Age and sex differences in brain metabolite concentrations in early life are not well understood. We examined the associations of age and sex with brain metabolite levels in healthy neonates, and investigated the associations between neonatal brain metabolite concentrations and developmental outcomes. Forty-one infants (36–42 gestational weeks at birth; 39% female) of predominantly Hispanic/Latina mothers (mean 18 years of age) underwent MRI scanning approximately two weeks after birth. Multiplanar chemical shift imaging was used to obtain voxel-wise maps of N-acetylaspartate (NAA), creatine, and choline concentrations across the brain. The Bayley Scales of Infant and Toddler Development, a measure of cognitive, language, and motor skills, and mobile conjugate reinforcement paradigm, a measure of learning and memory, were administered at 4 months of age. Findings indicated that postmenstrual age correlated positively with NAA concentrations in multiple subcortical and white matter regions. Creatine and choline concentrations showed similar but less pronounced age related increases. Females compared with males had higher metabolite levels in white matter and subcortical gray matter. Neonatal NAA concentrations were positively associated with learning and negatively associated with memory at 4 months. Age-related increases in NAA, creatine, and choline suggest rapid development of neuronal viability, cellular energy metabolism, and cell membrane turnover, respectively, during early life. Females may undergo earlier and more rapid regional developmental increases in the density of viable neurons compared to males.

Decreased brain volumes in infants with prenatal opioid exposure

Background/Objective: Previous small studies have shown that prenatal opioid-exposed (POE) infants and older children display decreased cerebral, cerebellar, or subcortical brain volumes. However, these studies are plagued by suboptimal reference standards or were unable to correct for the influence of other environmental factors in older children. Therefore, our goal was to study differences in brain volume of POE infants when compared to a geographically matched population. We hypothesized that there will be a significant decrease in total brain volume of the POE infants in comparison to the non-opioid exposed control infants, including a reduction in the cerebellar volume. &#x0D; &#x0D; Methods: This was an IRB approved prospective study of mothers and infants with POE and controls without POE. All recruited infants underwent MRI scans of the brain before they reached a corrected age of 2 months. The T1-weighted MRI images were analyzed by Infant FreeSurfer and segmented into ROIs. The segmentations were manually checked and edited. An ANOVA analysis was performed to compare the cerebellar and total brain volume datasets. We corrected for gender, corrected gestational age at MRI scan, and total brain volume where necessary. &#x0D; &#x0D; Results: 42 infants were included in the study, 21 with POE and 21 control infants. There was a significant difference in the mean gestational age of POE infants (38.28±2.13) compared to control infants (39.42±0.72). On quantitative analysis, the POE group had a significantly reduced total brain and supratentorial volume in comparison to the controls. The cerebellar volume was also significantly smaller in POE, but this significance did not persist when the total brain volume was included in the model. &#x0D; &#x0D; Conclusion: The supratentorial region is affected disproportionately more than the cerebellum in POE. Specific reductions in cortical, subcortical, and white matter volume need to be further investigated and their influence on developmental outcomes need to be studied.

A Nomogram for Pretreatment Prediction of Response to Induction Chemotherapy in Locally Advanced Hypopharyngeal Carcinoma.

BackgroundInduction chemotherapy (IC) significantly improves the rate of larynx preservation; however, some patients could not benefit from it. Hence, it is of clinical importance to predict the response to IC to determine the necessity of IC. We aimed to develop a clinical nomogram for predicting the treatment response to IC in locally advanced hypopharyngeal carcinoma.MethodsWe retrospectively include a total of 127 patients with locally advanced hypopharyngeal carcinoma who underwent MRI scans prior to IC between January 2014 and December 2017. The clinical characteristics were collected, which included age, sex, tumor location, invading sites, histological grades, T-stage, N-stage, overall stage, size of the largest lymph node, neutrophil-to-lymphocyte ratio, hemoglobin concentration, and platelet count. Univariate and multivariate logistic regression was used to select the significant predictors of IC response. A nomogram was built based on the results of stepwise logistic regression analysis. The predictive performance and clinical usefulness of the nomogram were determined based on the area under the curve (AUC), calibration curve, and decision curve.ResultsAge, T-stage, hemoglobin, and platelet were four independent predictors of IC treatment response, which were incorporated into the nomogram. The AUC of the nomogram was 0.860 (95% confidence interval [CI]: 0.780-0.940), which was validated using 3-fold cross-validation (AUC, 0.864; 95% CI: 0.755-0.973). The calibration curve demonstrated good consistency between the prediction by the nomogram and actual observation. Decision curve analysis shows that the nomogram was clinically useful.ConclusionThe proposed nomogram resulted in an accurate prediction of the efficacy of IC for patients with locally advanced hypopharyngeal carcinoma.

RONC-26. A CASE OF RADIATION NECROSIS OF THE CEREBELLUM 16 YEARS AFTER CHEMORADIOTHERAPY FOR MEDULLOBLASTOMA

BACKGROUNDIf new lesions are observed during follow-up of the malignant tumor after treatment, it is difficult to distinguish whether the tumor is a recurrent lesion, secondary cancer, or radiation necrosis of the brain. We have encountered a patient with symptomatic radiation necrosis of the cerebellum 16 years after treatment of medulloblastoma. CASE PRESENTATION: A 24-year-old man who had received a tumor resection and chemoradiotherapy for cerebellar medulloblastoma at the age of 8 presented with dizziness. For the past 16 years, there was no recurrence of the tumor. He subsequently underwent MRI scan, and T1-Gd image showed enhanced lesion in the right cerebellar peduncle. Cerebrospinal fluid cytology analysis was negative for tumor. We suspected tumor reccurence or secondary cancer, and performed lesion biopsy. The result of the pathological examination was radiation necrosis of the cerebellum. DISCUSSION: The interval of radiation necrosis of the brain and radiotherapy can vary from months to more than 10 years. So, whenever a new lesion is identified, radiation brain necrosis must be envisioned. According to guidelines in Japan, there is no absolute examination for discriminating tumor recurrence from radiation brain necrosis and diagnosis by biopsy may be required.CONCLUSIONWe experienced a case of symptomatic radiation necrosis of the cerebellum 16 years after treatment. In patients showing new lesion after long periods of time, the possibility of radiation necrosis to be considered.

Mild to moderate levels of anxiety in a healthy population cohort are related to face recognition with negative emotions and white matter integrity

AbstractBackgroundThe face recognition tasks were applied to test the healthy population cohort with mild to moderate levels of anxiety and they underwent MRI scans to evaluate their brains' white matter integrity.MethodMAP‐MRI analysis applied to estimate diffusion indexes Generalised Fractional Anisotropy (GFA) of segmented white matter tracts in a healthy (N=174) population‐based sample (mean MMSE 28.39) from the Cambridge Centre for Ageing and Neuroscience (Cam‐CAN) data including normal adults ages 18‐88 to examine microstructural properties of specific association fiber tracts involved in face recognition processing. Half sample (n=88) had anxiety symptoms ( Hospital Anxiety Scale 9.7) and half sample (n=88) were matched with age and sex and without anxiety symptoms. Two kinds of behavioral face tests to white matter measures including three pairs of association tracts, namely inferior fronto‐occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF) and uncinated fasciculus (UF). The two kinds of behavioral face tests applied were Benton Test of Facial Recognition which assesses the ability to match pictures of unfamiliar faces with variation of head orientation and lighting, and face recognition test of emotion assessing recognition of positive emotion (happiness), negative emotions (angry, disgust, fear, and sad) and surprise emotion. Paired sample t test were applied to compare the two groups' HAS, behavioral tests, and GFA of white matter tracts.ResultPaired t test results showed hospital Anxiety Scale, mean reaction time (RT) of face recognition test in negative emotion, GFA of left IFOF and left UF were significantly different in two groups. Pearson correlation analysis showed mean RT of face recognition test in negative emotion was significantly negative correlated with GFA of left UF.ConclusionHealthy life‐span population cohort with mild to moderate anxiety symptoms spent longer time recognizing faces with negative emotions and white matter integrity of the specific tract UF reflected this characteristic. There was brain‐behavior relationship.

The API Generation program: Biomarker phenotyping of cognitively unimpaired participants screened in Generation study 1 and Generation study 2

AbstractBackgroundAPI Generation Program evaluated the effectiveness of the BACE1 inhibitor umibecestat and the active immunotherapy CAD106 in delaying the onset of AD symptoms in APOE4 carriers. Data from imaging (vMRI and PET scans), and fluid biomarkers (blood and CSF) were collected during the 12‐week Screening phase. In this presentation, we will summarize results across the two studies and investigate the relationships between the various biomarkers and key baseline characteristics.MethodAmyloid levels were assessed via CSF and/or Amyloid PET scan in both studies for the APOE4 carriers. Generation Study 2 enrolled heterozygotes based on the following elevated amyloid inclusion criteria: Roche Elecsys® CSF p‐Tau/Abeta42 ratio &gt; 0.024 and/or PET scans with any of the 3 amyloid F18 tracers (florbetapir, flutemetamol or florbetaben). If the centralized visual read of PET scan was negative, the SUVr was calculated (cortical composite in reference to whole cerebellum) for the three tracers in order to assess borderline cases. Thresholds for amyloid positivity equivalent to SUVR of 1.1 with florbetapir were used for the final decision on inclusion.ResultAcross both studies, over 500 lumbar punctures, 2700 amyloid PET scans and about 150 tau PET scans (conducted using flortaucipir) were performed. In Generation Study 1, over 200 FDG PET scans were also performed. Participants underwent amyloid testing during screening, blood sampling (plasma and serum) and underwent MRI scans for safety and to measure brain volumes. All baseline biomarker data will be presented, including available concentrations from CSF Tau/p‐Tau/Aβ42/Aβ40 along with the eligibility ratio for pTau/ab42. In about 150 participants, concordance between elevated/non elevated amyloid status by CSF and PET (using centiloids) will be shown. Baseline brain volume (whole brain and hippocampus) will be summarized for the different co‐variates (age, sex, cognition, genotype and amyloid status). Correlations among the various fluid biomarkers and imaging will be discussed.ConclusionThese data describe the biomarker signature of the world’s largest cohort of cognitively unimpaired APOE4 carriers with and without elevated amyloid. The anonymized study data, biomarker samples as well as images collected will be shared with the scientific community after study completion and reporting. ELECSYS is a registered trademark of Roche.

Patient with COVID – 19 infection presenting with acute 6th cranial nerve palsy: A case report

We present a case of a 55 year old lady, hypertensive and diabetic who was infected with COVID-19 presenting with acute 6th cranial nerve palsy. The patient was diagnosed with COVID-19 on Sept 01 2020. Seven days later she developed double vision and headache. At that point on complete neurological examination including examination of cranial nerves she was found to have 6th cranial nerve (Abducens) palsy with convergent squint. As the patients cranial nerves were all intact initially it is suspected that her 6th nerve palsy was related to the viral illness. She was assessed by ophthalmologist and neurologist. She underwent MRI scan of the brain to look for other causes of 6th nerve palsy and it was unremarkable. After almost one week of continued inpatient management her diplopia improved but she still complained of intermittent diplopia with convergent squint.&#x0D; Bangladesh Crit Care J September 2020; 8(2): 129-130