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Curation of large, diverse MRI datasets via multi-institutional collaborations can help improve learning of generalizable synthesis models that reliably translate source- onto target-contrast images. To facilitate collaborations, federated learning (FL) adopts decentralized model training while mitigating privacy concerns by avoiding sharing of imaging data. However, conventional FL methods can be impaired by the inherent heterogeneity in the data distribution, with domain shifts evident within and across imaging sites. Here we introduce the first personalized FL method for MRI Synthesis (pFLSynth) that improves reliability against data heterogeneity via model specialization to individual sites and synthesis tasks (i.e., source-target contrasts). To do this, pFLSynth leverages an adversarial model equipped with novel personalization blocks that control the statistics of generated feature maps across the spatial/channel dimensions, given latent variables specific to sites and tasks. To further promote communication efficiency and site specialization, partial network aggregation is employed over later generator stages while earlier generator stages and the discriminator are trained locally. As such, pFLSynth enables multi-task training of multi-site synthesis models with high generalization performance across sites and tasks. Comprehensive experiments demonstrate the superior performance and reliability of pFLSynth in MRI synthesis against prior federated methods.
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Aprendizagem , Imageamento por Ressonância Magnética , Humanos , Reprodutibilidade dos TestesRESUMO
We first aimed to investigate resting-state functional connectivity (rs-FC) differences between adolescents exposed to SARS-CoV-2 and healthy controls. Secondly, the moderator effect of PLEs on group differences in rs-FC was examined. Thirdly, brain correlates of inflammation response during acute SARS-CoV-2 infection were investigated. Eighty-two participants aged between 14 and 24 years (SARS-CoV-2 (n = 35), controls (n = 47)) were examined using rs-fMRI. Seed-based rs-FC analysis was performed. The positive subscale of Community Assessment of Psychotic Experiences-42 (CAPE-Pos) was used to measure PLEs. The SARS-CoV-2 group had a lesser rs-FC within sensorimotor network (SMN), central executive network (CEN) and language network (LN), but an increased rs-FC within visual network (VN) compared to controls. No significant differences were detected between the groups regarding CAPE-Pos-score. However, including CAPE-Pos as a covariate, we found increased rs-FC within CEN and SN in SARS-CoV-2 compared to controls. Among the SARS-CoV-2 group, neutrophil/lymphocyte and thrombocyte*neutrophil/lymphocyte ratio was correlated with decreased/increased FC within DMN and SN, and increased FC within CEN. Our results showed rs-FC alterations within the SMN, CEN, LN, and VN among adolescents exposed to SARS-CoV-2. Moreover, changes in rs-FC associated with PLEs existed in these adolescents despite the absence of clinical changes. Furthermore, inflammation response was correlated with alterations in FC within the triple network system.
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COVID-19 , SARS-CoV-2 , Humanos , Adolescente , Adulto Jovem , Adulto , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , COVID-19/diagnóstico por imagem , Encéfalo/diagnóstico por imagemRESUMO
OBJECTIVE: Our understanding of IgG4-RD and pachymeningitis has grown substantially, but the optimal approach for diagnosis, management, and long-term outcomes is still an area of uncertainty. METHODS: HUVAC is a database for IgG4-RD patients, this database was retrospectively evaluated for pachymeningeal disease. Demographic, clinical, serological, imaging, histopathological data, and treatment details were re-interpreted in patients with pachymeningitis. RESULTS: Among 97 patients with IgG4-RD, 6 (6.2%) had pachymeningitis. None of these patients had extracranial features, and also, in most of the patients, serum IgG4 levels were normal. Tentorium cerebelli and transverse sinus dura were the most commonly involved in the posterior fossa. During 18 months of median follow-up on steroid+-rituximab, none of them relapsed as pachymeningitis. CONCLUSION: Our patients were mainly older males with sole neurological involvement. Non-specific headache was the most common manifestation, and serum IgG4 levels were not useful for diagnosis. Typical radiology and tentorial thickening should suggest IgG4-RD and prompt an early biopsy. Moreover, accompanying hypophysitis could also be a clue. With steroids+ rituximab treatment, no relapse related to meningeal involvement was seen in long-term follow-up.
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Doença Relacionada a Imunoglobulina G4 , Meningite , Masculino , Humanos , Imunoglobulina G , Doença Relacionada a Imunoglobulina G4/diagnóstico , Doença Relacionada a Imunoglobulina G4/tratamento farmacológico , Doença Relacionada a Imunoglobulina G4/patologia , Seguimentos , Rituximab/uso terapêutico , Estudos Retrospectivos , Meningite/diagnóstico por imagem , Meningite/tratamento farmacológicoRESUMO
OBJECTIVES: Beta-propeller protein-associated neurodegeneration (BPAN) is a rare X-linked dominant neurodegenerative disease, which is characterized by iron accumulation in the basal ganglia. BPAN is associated with pathogenic variation in WDR45, which has been reported almost exclusively in females most probably due to male lethality in the hemizygous state. METHODS: Whole exome sequencing (WES) and targeted deep sequencing were performed for a male with a clinical diagnosis of BPAN at the age of 37. RESULTS: The novel frameshift variant in WDR45 detected by WES was further analyzed with targeted resequencing to detect a mosaic variant with a level of 85.5% in the blood sample of the proband. DISCUSSION: Although the main role of WDR45 remains elusive, recent studies show that WDR45 may contribute to neurodegeneration through defects in autophagy, iron storage and ferritin metabolism, mitochondria organization, and endoplasmic reticulum homeostasis. The extend of spatiotemporal haploinsufficiency of WDR45 frameshifting variants caused by mosaicism in males may lead to variable clinical severity, which may be hard to elaborate clinically. Promising genetic analysis strategies using targeted deep sequencing may help determine the clinical outcome of somatic mosaicism in neurological disorders including BPAN. Additionally, we suggest that deep sequencing should be conducted in cerebrospinal fluid samples to provide more reliable results in terms of reflecting the mosaicism level in the brain for future studies.
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OBJECTIVE: The aim of this study was to evaluate brain connectivity by diffusion tensor imaging (DTI) in schizophrenia patients with clozapine-induced obsessive compulsive symptoms (OCS). METHODS: Eighteen schizophrenia patients, nine of which had clozapine-induced OCS (Clz-OCS (+)), 9 without OCS (Clz-OCS (-)) and 9 healthy controls were included. Psychopathology was evaluated with Positive and Negative Syndrome Scale and Yale-Brown Obsession and Compulsion Scale in the patient groups. All groups were assesed with neurocognitive tests and DTI. RESULTS: Tract-Based Spatial Statistics based comparison of DTI revealed lower fractional anisotropy in the genu of corpus callosum (CC), right cingulum, left frontal white matter (WM) in the Clz-OCS (+) group, compared to controls. Fractional anisotropy was found to be lower in the bilateral occipital WM and higher in the bilateral medial temporal regions, anterior limb of internal capsule, cingulum, frontoparietal peripheral WM, right external capsule and genu of CC in Clz-OCS (+) patients compared to Clz-OCS (-). CONCLUSIONS: WM integrity in several pathways such as cortico-striato-thalamo-cortical circuitry and orbito-frontal tracts seems to be affected differently in patients with Clz-OCS (+). Different neuroplastic effects of clozapine leading to occurrence of OCS in a subgroup of patients is possible, and needs further evaluation by longitudinal follow-up studies.
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Clozapina , Transtorno Obsessivo-Compulsivo , Esquizofrenia , Humanos , Imagem de Tensor de Difusão/métodos , Clozapina/efeitos adversos , Esquizofrenia/tratamento farmacológico , Encéfalo , Transtorno Obsessivo-Compulsivo/diagnóstico por imagemRESUMO
Claude syndrome is a rare midbrain stroke syndrome characterized by ipsilateral third cranial nerve palsy and contralateral hemiataxia. So far, only a few cases have been reported in childhood. We present two children with Claude syndrome at 9 and 15 years of age. The typical clinical picture was consistent with brain magnetic resonance imaging findings. A thorough investigation regarding the underlying etiology revealed no definite diagnosis but clues suggestive of probable neuro-Behcet disease. Awareness of pediatric neurologists on arterial ischemic stroke has been increasing over the past decades, enabling timely diagnosis and appropriate management of rare childhood cases with midbrain stroke.
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Síndrome de Behçet , Infartos do Tronco Encefálico , Doenças do Nervo Oculomotor , Acidente Vascular Cerebral , Criança , Humanos , Síndrome de Behçet/diagnóstico , Síndrome de Behçet/diagnóstico por imagem , Doenças do Nervo Oculomotor/complicações , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral/complicações , Infartos do Tronco Encefálico/complicaçõesRESUMO
INTRODUCTION: Sleep is a modulator of glymphatic activity which is altered in various sleep disorders. Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness (EDS), rapid onset of rapid eye movement (REM) sleep, cataplexy, disturbed night sleep with fragmentation. It is categorized into two types, type 1 (NT1) and type 2 (NT2) depending on the presence of cataplexy and/or absence of orexin. We sought for alterations in glymphatic activity in narcoleptic patients using diffusion tensor imaging (DTI) along perivascular space (ALPS) index on magnetic resonance imaging (MRI). MATERIAL AND METHODS: Adult patients diagnosed with NT1 or NT2 who had polysomnography (PSG) and MRI with DTI were included in the study. Sleep recording included Epworth Sleepiness Scale (ESS) score, sleep latency during multiple sleep latency test (MSLT), sleep efficiency during night PSG, wake after sleep onset (WASO), REM sleep latency during PSG, percentage of non-REM (NREM), REM sleep and wakefulness during night PSG. DTI-ALPS index was calculated for each patient and age-sex matched healthy control(HC)s. RESULTS: The study group was composed of 25 patients [F/M = 15/10, median age = 34 (29.5-44.5)], 14 with NT1 and 11 with NT2 disease. ESS, WASO and percentage of wakefulness were significantly higher in NT1 patients (p < 0.05). Mean DTI-ALPS was not significantly different neither between narcoleptic patients and HCs, nor between NT1 and NT2 patients (all, p > 0.05). However, DTI-ALPS was negatively correlated with WASO (r = -0.745, p = 0.013) and percentage of wakefulness (r = -0.837, p = 0.005) in NT1 patients. DTI-ALPS correlated negatively with percentage of N1 sleep (r = -0.781, p = 0.005) but positively with REM percentage (r = 0.618, p = 0.043) in NT2 patients. CONCLUSION: In this study, DTI-ALPS was not significantly different in narcoleptic patients than the HCs. However, the glymphatic index as assessed by DTI-ALPS correlated with PSG parameters; negatively with WASO, percentage of wakefulness in NT1, percentage of N1 sleep in NT2, and positively with REM sleep in NT2. A tendency for a reduction in DTI-ALPS in NT1 patients compared to both NT2 patients and HCs was also found. These findings might show the first evidence of an alteration of glymphatic activity, especially in NT1 patients, thus warrant further prospective studies in larger size of narcoleptic patient cohorts.
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Cataplexia , Narcolepsia , Adulto , Humanos , Imagem de Tensor de Difusão , Estudos Prospectivos , Narcolepsia/diagnóstico , SonoRESUMO
OBJECTIVE: Our aim is to describe an unusual pattern of craniocervical pneumatization resulting in a spontaneous fracture in a patient, who presented with tinnitus. METHODS: Temporal CT was ordered in a patient with tinnitus lasting over a year. His audiogram was normal. No history of previous trauma, recent flight, diving, or weight lifting was present. Further questioning revealed his habitual Valsalva maneuvers to relieve symptoms of nasal congestion. RESULTS: Temporal CT showed abnormal pneumatization of the occipital bone and C1 vertebra. A definite cortical defect resulted with the presence of air around the neighboring soft tissues. The emphysema was most prominent in the suboccipital fossa but it was also seen in the epidural space of the spinal canal. CONCLUSION: Abnormal pneumatization of the skull base and cervical vertebra can be symptomatic due to its tendency to fracture. The presumed cause of pneumatization in this patient is habitual Valsalva maneuvers.
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Zumbido , Humanos , Tomografia Computadorizada por Raios X , Base do Crânio/diagnóstico por imagem , Vértebras Cervicais , Osso OccipitalRESUMO
BACKGROUND: Extracorporeal membrane oxygenation (ECMO) can be associated with severe neurological complications increasing morbidity and mortality. We aimed to evaluate imaging findings in patients with neurological complications associated with ECMO. METHODS: Children ( < 18 years) who had ECMO support and received cross-sectional imaging (cranial CT and/ or MRI) were retrospectively evaluated. Age, gender, clinical and imaging findings were documented and the relation to ECMO duration and survival rates with imaging findings and imaging time (during ECMO or after weaning) were examined. RESULTS: Twenty children who had cranial CT/MRI during (n=6) ECMO and after weaning (n=14) were included in the study. The median duration of ECMO was 12.5 days (IQR=5-25 days) with a survival rate of 65%. Fourteen patients had positive imaging findings including ischemic stroke (n=4), hemorrhagic stroke (n=4), hypoxicischemic encephalopathy (n=2), posterior reversible encephalopathy syndrome (PRES) (n=3) and cerebral vein thrombosis (n=1). The duration of ECMO and survival rates did not significantly differ between patients with positive and unremarkable imaging findings. However, the survival rate was significantly higher (p < 0.001) and the duration of ECMO was significantly lower in patients scanned after weaning compared to patients imaged during ECMO support (p=0.033). CONCLUSIONS: Our series revealed PRES in ECMO-related neurologic events in addition to commonly reported thrombotic and hemorrhagic stroke in the literature. Availability of cross-sectional imaging and awareness of radiologists to these complications during ECMO or after weaning help in prompt diagnosis and treatment.
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Oxigenação por Membrana Extracorpórea , Acidente Vascular Cerebral Hemorrágico , Síndrome da Leucoencefalopatia Posterior , Trombose , Criança , Humanos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
PURPOSE lthough clinical ophthalmologic findings have been reported, no study documented magnetic resonance imaging (MRI) findings in mucopolysaccharidosis (MPS) type VI. The aim of this study was to determine the ophthalmologic imaging findings of MPS type VI in the pediatric age group retrospectively. METHODS Brain MRIs of 10 patients with MPS type VI and 49 healthy children were evaluated independently by two pediatric radiologists for the following characteristics: globe volume, ocular wall thickness, and optic nerve sheath diameter for each orbit. The means of the measurement of each group were compared by using an independent t-test. Agreement and bias between reviewers were assessed by intra-class correlation coefficients (ICC). RESULTS A total of 59 children [32 girls (54.23%), 27 boys (45.77%); age range, 4-16 years; mean age, 10.37 ± 3.73 years] were included in the study. Statistical analysis revealed smaller eyeballs and thicker ocular walls of patients with MPS type VI (P < .001 and P < .001, respectively). However, there was no statistically significant difference in terms of optic nerve sheath diameter between the two groups (P=.648). CONCLUSION Patients with MPS type VI displayed reduced globe volumes and increased ocular wall thicknesses compared to the healthy children. Therefore, we recommend that ophthalmologic imaging findings might prove to be an auxiliary tool in the diagnosis of MPS patients.
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Mucopolissacaridose VI , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Mucopolissacaridose VI/diagnóstico , Mucopolissacaridose VI/patologia , Estudos RetrospectivosRESUMO
OBJECTIVE: The generation of numerous sequences and quantitative data in a short scanning time is the most potential advantage of Synthetic MRI (SyMRI). We aimed to test detection of the tubers and to determine underlying tissue characteristics, and morphometric alterations in the brain of pediatric tuberous sclerosis complex (TSC) patients, using SyMRI. METHODS: Conventional brain MRI (cMRI) and SyMRI were prospectively obtained from 10 TSC patients and 18 healthy control subjects (HCs). Two neuroradiologists independently evaluated tubers on both scans. Additionally, automatically segmented volume calculation and myelin quantification, including the subcortical part of the tubers and normal-appearing brain parenchyma (NABP) of patients, were carried out using SyMRI. RESULTS: The cMRI and SyMRI comparison showed a very good correlation on the detection of the tubers (k = 0.82-0.94). Automatic segmentation of Non-gray matter/white matter/cerebrospinal fluid (Non), %Non/brain parenchymal volume, and %Non/intracranial volume was significantly higher; however, %Myelin/intracranial volume and %Myelin/brain parenchymal volume were significantly lower in the TSC patients (p < 0.05). The proton density values were significantly increased, and myelin fraction volume and myelin-correlated compound values were significantly decreased in the NABP in TSC patients on myelin maps (p < 0.05). The white-matter volume, myelin and white-matter fractional volume, longitudinal relaxation rate, transverse relaxation rate, and myelin-correlated compound values were significantly decreased in the subcortical part of tubers on quantification maps (p < 0.001) in TSC patients. CONCLUSION: SyMRI enables the detection of cortical tubers and is a developing tool in the quantification of morphometric and tissue alterations in pediatric TSC patients with a rational scanning time.
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Accumulation of intermediate metabolites due to enzyme deficiencies and demyelination can provoke inflammation in genetic leukodystrophies. Thirty patients with genetic leukodystrophy and 48 healthy control sera were tested for anti-myelin oligodendrocyte glycoprotein (MOG) antibodies by fixed and/or live cell-based assays. MOG-IgG was detected in two late infantile metachromatic leukodystrophy (MLD) cases, both of which were also weakly positive for IgG1, and one with IgG3 as the dominant anti-MOG IgG subclass. MOG-IgG was borderline positive in a vanishing white matter (VWM) disease patient. These results suggest that inherited metabolic or degenerative processes can have an autoimmune component, possibly as an epiphenomenon.
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Doenças Desmielinizantes , Doenças Neurodegenerativas , Autoanticorpos , Humanos , Imunoglobulina G , Glicoproteína Associada a Mielina , Glicoproteína Mielina-Oligodendrócito , Oligodendroglia/metabolismoRESUMO
Magnetic resonance imaging (MRI) offers the flexibility to image a given anatomic volume under a multitude of tissue contrasts. Yet, scan time considerations put stringent limits on the quality and diversity of MRI data. The gold-standard approach to alleviate this limitation is to recover high-quality images from data undersampled across various dimensions, most commonly the Fourier domain or contrast sets. A primary distinction among recovery methods is whether the anatomy is processed per volume or per cross-section. Volumetric models offer enhanced capture of global contextual information, but they can suffer from suboptimal learning due to elevated model complexity. Cross-sectional models with lower complexity offer improved learning behavior, yet they ignore contextual information across the longitudinal dimension of the volume. Here, we introduce a novel progressive volumetrization strategy for generative models (ProvoGAN) that serially decomposes complex volumetric image recovery tasks into successive cross-sectional mappings task-optimally ordered across individual rectilinear dimensions. ProvoGAN effectively captures global context and recovers fine-structural details across all dimensions, while maintaining low model complexity and improved learning behavior. Comprehensive demonstrations on mainstream MRI reconstruction and synthesis tasks show that ProvoGAN yields superior performance to state-of-the-art volumetric and cross-sectional models.
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Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Estudos Transversais , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodosRESUMO
PURPOSE: To assess polar vessel presence and enhancement 4DCT imaging and their relation with biochemical and histopathological features. METHODS: Patients with primary hyperparathyroidism and preoperative 4DCT imaging were screened retrospectively and those with histopathologically proven diagnosis of PA were included. Biochemical findings, densitometric measurements (HUprecontrast, HUarterial, HUvenous, HUwash-in, HUwash-out, HUretained) and CTvolume of PA on 4DCT, presence of a polar vessel (PV), and histopathological features were recorded. Correlations between serum PTH, calcium levels and densitometric measurements of PA on 4DCT were investigated. Differences between subgroups created according to PV presence were also evaluated. RESULTS: Thirty-nine patients were enrolled (F/M = 32/7, median age = 57, interquartile range = 50-62 years). In all patients, serum PTH levels positively correlated with CTvolume (r = 0.398, p = 0.012) but negatively correlated with HUarterial (r = - 0.366; p = 0.022), HUvenous (r = - 0.452; p = 0.004) and HUretained (r = - 0.421; p = 0.008). In PV (-) PAs, PTH levels were positively correlated with CTvolume (r = 0.608, p ≤ 0.002) and negatively with HUarterial (r = - 0.449, p ≤ 0.028), HUvenous (r = - 0.560, p = 0.004), HUwash-in (r = - 0.460, p = 0.024), and HUretained (r = - 0.539, p = 0.007). No correlation between PTH levels and densitometric measurements was found in PV (+) PAs. HUwash-in and HUwash-out were significantly higher in PV (+) PAs compared to PV (-) PAs (p = 0.021 and p = 0.033, respectively). Histopathologic features revealed no difference according to the presence of PV. CONCLUSION: PTH levels might have an association with imaging findings of PAs, especially when categorized with respect to PV presence. PTH levels were negatively correlated with degree of enhancement in PV (-) PAs. Therefore, radiologists should be aware that in patients with high serum PTH levels and without a discernible PV, PA might be difficult to localize.
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Adenoma , Neoplasias das Paratireoides , Adenoma/diagnóstico por imagem , Adenoma/patologia , Tomografia Computadorizada Quadridimensional , Humanos , Pessoa de Meia-Idade , Hormônio Paratireóideo , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/patologia , Estudos RetrospectivosRESUMO
PURPOSE: To compare the inter-center cranial computed tomography (CT) acquisition rates, CT findings, CT related radiation dose, and variability of CT acquisition parameters for neurologic events among patients with implantable cardioverter-defibrillator (ICD) or left ventricular assist device (LVAD). METHODS: A total of 224 patients [ICD group (n = 155) and LVAD group (n = 69)] who had at least one cranial CT scan were enrolled from three medical centers. The variability and effect of the number, indication, and findings of cranial CT scans as well as CT acquisition parameters including tube potential, tube current, tube rotation time (TI), slice collimation (cSL), and spiral or sequential scanning techniques on CT dose index volume (CTDIvol), total dose length product (DLP) were analyzed. RESULTS: The mean DLP value of Center A and mean CTDIvol values of Center A and C were significantly lower than Center B (p < 0.001). The mean CTDIvol and DLP values in the ICD group were substantially lower than the LVAD group (p<0.001). The most potent parameters causing the changes in CTDIvol and DLP were kV, mAs values, and CT scanning technique as sequential or spiral according to multivariate linear regression analysis. CONCLUSION: Cranial CT acquisition parameters and radiation doses vary significantly between centers, which necessitates optimization of cranial CT protocols to overcome the cumulative radiation dose burden in patients with neurologic events.
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Desfibriladores Implantáveis , Exposição à Radiação , Desfibriladores Implantáveis/efeitos adversos , Humanos , Doses de Radiação , Cintilografia , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: Synthetic MRI (SyMRI) enables to quantify brain tissue and morphometry. We aimed to investigate the WM and myelin alterations in patients with unilateral hippocampal sclerosis (HS) with SyMRI. METHODS: Adult patients with isolated unilateral HS and age-matched control subjects (CSs) were included in this study. The SyMRI sequence QRAPMASTER in the coronal plane perpendicular to the hippocampi was obtained from the whole brain. Automatic segmentation of the whole brain was processed by SyMRI Diagnostic software (Version 11.2). Two neuroradiologists also performed quantitative analyses independently from symmetrical 14 ROIs placed in temporal and extratemporal WM, hippocampi, and amygdalae in both hemispheres. RESULTS: Sixteen patients (F/M = 6/10, mean age = 32.5 ± 11.3 years; right/left HS: 8/8) and 10 CSs (F/M = 5/5, mean age = 30.7 ± 7 years) were included. Left HS patients had significantly lower myelin and WM volumes than CSs (p < .05). Myelin was reduced significantly in the ipsilateral temporal lobe of patients than CSs, greater in left HS (p < .05). Histopathological examination including luxol fast blue stain also revealed myelin pallor in all of 6 patients who were operated. Ipsilateral temporal pole and sub-insular WM had significantly reduced myelin than the corresponding contralateral regions in patients (p < .05). No significant difference was found in WM values. GM values were significantly lower in hippocampi in patients than CSs (p < .05). CONCLUSION: SyMRI revealed myelin reduction in the ipsilateral temporal lobe and sub-insular WM of patients with HS. Whether this finding correlates with electrophysiological features and SyMRI could serve as lateralization of temporal lobe epilepsy need to be investigated.
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Epilepsia do Lobo Temporal , Bainha de Mielina , Adulto , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Bainha de Mielina/patologia , Esclerose/diagnóstico por imagem , Esclerose/patologia , Adulto JovemRESUMO
The chronological age of a person is a key determinant of etiology and prognosis in the setting of ischemic stroke. Telomere length, an indicator of biological aging, progressively shortens with every cell cycle. Herein, we determined telomere length from peripheral blood leukocytes by Southern blot analyses in a prospective cohort of ischemic stroke patients (n = 163) and equal number of non-stroke controls and evaluated its association with various ischemic stroke features including etiology, severity, and outcome. A shorter telomere length (i.e. lowest quartile; ≤ 5.5 kb) was significantly associated with ischemic stroke (OR 2.95, 95% CI 1.70-5.13). This significant relationship persisted for all stroke etiologies, except for other rare causes of stroke. No significant association was present between admission lesion volume and telomere length; however, patients with shorter telomeres had higher admission National Institutes of Health Stroke Scale scores when adjusted for chronological age, risk factors, etiology, and infarct volume (p = 0.046). On the other hand, chronological age, but not telomere length, was associated with unfavorable outcome (modified Rankin scale > 2) and mortality at 90 days follow-up. The association between shorter telomere length and more severe clinical phenotype at the time of admission, might reflect reduced resilience of cerebral tissue to ischemia as part of biological aging.
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Isquemia Encefálica/genética , Encurtamento do Telômero , Idade de Início , Idoso , Envelhecimento/genética , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/patologia , Estudos de Casos e Controles , Cromossomos Humanos/ultraestrutura , Comorbidade , Feminino , Predisposição Genética para Doença , Humanos , Leucócitos/ultraestrutura , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Risco , Fatores de Risco , Fumar/epidemiologia , Turquia/epidemiologiaRESUMO
Temporal encephaloceles (TEs) are one of the cause of refractory temporal lobe epilepsy (TLE). We reviewed the neuroimaging and video-electroencephalography (EEG) records of epilepsy patients who underwent temporal lobectomy in our center to investigate frequency of TEs. We retrospectively reevaluated 294 patients who underwent epilepsy surgery in our tertiary epilepsy centre between January 2010 and March 2019 and included 159 patients (78 females, 49 %; 81 males) who had temporal lobectomy. Preoperatively, TEs were reported in 3 of 159 patients (1 female, 2 males). After reevaluation 4 more patients with TEs (1 female, 3 males) were added. The ratio of TE in patients who underwent temporal lobectomy increased from 1.8 % (n=3) to 4,4 % (n=7). The median ages were 18 (range 16-22) versus 10 years (range 5-17) at habitual seizure onset and the median of epilepsy duration was 5 (range 3-15) versus 175 (range 11-25) years between patients with and without TE. Habitual seizure onset age was significantly higher (p =, 007) in the patients with encephalocele and epilepsy duration was shorter (p =, 003) than patients without encephalocele. The ictal EEG records of all patients TE rhythmic delta activity which is suggested neocortical temporal lobe onset seizures. 4 of 7 patients' PET imaging showed temporal lobe hypometabolism compatible with ipsilateral to the TEs. The three patients underwent anterior temporal lobectomy without amygdalohippocampectomy and others had anterior temporal lobectomy with amygdalohippocampectomy. We suggested that there might be some clues for temporal encephalocele, an easily overlooked cause in patients with nonlesional temporal lobe epilepsy.TLE patients with TE had relatively late onset of epilepsy and rhythmic delta activity on ictal EEG. Also, temporal hypometabolism on PET may be a useful key to suspicion of TE.
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Encefalocele , Epilepsia do Lobo Temporal , Adolescente , Adulto , Lobectomia Temporal Anterior , Eletroencefalografia/métodos , Encefalocele/complicações , Encefalocele/diagnóstico por imagem , Encefalocele/cirurgia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/cirurgia , Resultado do Tratamento , Adulto JovemRESUMO
Multi-contrast MRI protocols increase the level of morphological information available for diagnosis. Yet, the number and quality of contrasts are limited in practice by various factors including scan time and patient motion. Synthesis of missing or corrupted contrasts from other high-quality ones can alleviate this limitation. When a single target contrast is of interest, common approaches for multi-contrast MRI involve either one-to-one or many-to-one synthesis methods depending on their input. One-to-one methods take as input a single source contrast, and they learn a latent representation sensitive to unique features of the source. Meanwhile, many-to-one methods receive multiple distinct sources, and they learn a shared latent representation more sensitive to common features across sources. For enhanced image synthesis, we propose a multi-stream approach that aggregates information across multiple source images via a mixture of multiple one-to-one streams and a joint many-to-one stream. The complementary feature maps generated in the one-to-one streams and the shared feature maps generated in the many-to-one stream are combined with a fusion block. The location of the fusion block is adaptively modified to maximize task-specific performance. Quantitative and radiological assessments on T1,- T2-, PD-weighted, and FLAIR images clearly demonstrate the superior performance of the proposed method compared to previous state-of-the-art one-to-one and many-to-one methods.
Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , HumanosRESUMO
BACKGROUND: Primary spinal, intradural, extramedullary Ewing sarcoma (PSIEES) is exceptionally uncommon. Here, we present an interesting pediatric case with a PSIEES diagnosis confirmed by the presence of a specific fusion protein in the tumor tissue and who then developed a cerebellar recurrence. We also reviewed the PSIEES cases in childhood reported in the literature. CASE: An 8.5-year-old boy was admitted to a local hospital with a one-month history of severe back and limb pain, and inability to move his lower limbs. Physical examination revealed paraparesis in the lower extremities. Spinal MRI revealed multiple intradural extramedullary masses at the L2-L3, L4-5 and L5-S1 levels. He underwent surgery and near total excision of all three masses were performed. Histopathological diagnosis of Ewing Sarcoma was confirmed with EWS-ERG gene rearrangement. The patient was treated according to EuroEwing chemotherapy protocol. A total dose of 4500 cGy radiotherapy was applied to the tumor location at L2-S1 paravertebral region. Eighteen months after the end of treatment, a mass in the left cerebellar hemisphere was determined. Gross total excision was performed. Histopathological examination of the tumor showed Ewing sarcoma. Radiological screening revealed isolated central nervous system recurrence. A total of 4500 cGy radiotherapy was applied. He is on a second-line treatment consisting of gemcitabine and docetaxel without any evidence of disease. CONCLUSIONS: Ewing Sarcoma with spinal intradural region in childhood is very rare. We could only find 17 pediatric cases reported in the literature. Neurological findings occur earlier in tumors of this region. The prognosis is worse than other extraosseous Ewing sarcoma.