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1.
J Comput Assist Tomogr ; 44(1): 43-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31789683

RESUMO

OBJECTIVE: The objective of this study was to investigate the frequency of hippocampal sulcus remnants (HSRs) in nonelderly adults using ultra-high-resolution 7T magnetic resonance (MR) images and their imaging features. METHODS: A total of 33 healthy adults underwent 7T MR, and multiplanar images of 66 temporal lobes were reviewed independently by 2 neuroradiologists. The detectability of the HSR was calculated. In addition, the interobserver agreement on the rating scale was evaluated using the κ statistic. RESULTS: Both observers identified HSRs with 7T MR images in all subjects. Excellent interobserver agreement was shown (κ = 1.0). The shape of HSRs was variable (spot-like, curvilinear, ovoid, or beaded appearance). Volumes of the HSRs were not correlated with age. CONCLUSIONS: Hippocampal sulcus remnants are commonly seen in healthy nonelderly adults using 7T MR imaging. Accurate diagnosis of HSR based on the microanatomy of hippocampus makes it easier to differentiate them from lesions, and it may help prevent unnecessary treatment.


Assuntos
Hipocampo/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Adulto , Algoritmos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Adulto Jovem
2.
Radiol Med ; 125(1): 80-86, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31529401

RESUMO

OBJECTIVE: To observe the structural changes of gray matter nuclei in patients with acute carbon monoxide intoxication by diffusion tensor imaging (DTI), quantify the degree of deep gray matter damage in the brain by adopting imaging technology and research the characteristics of the damage and its pertinence with memory and cognitive impairment. METHODS: Twenty-five patients with acute carbon monoxide intoxication and 25 healthy volunteers matched in sex and age were examined by routine head MRI and diffusion tensor imaging (DTI). Bilateral hippocampus, dater nucleus, thalamus, amygdala, globus pallidus and putamen were taken as regions of interest. The mean diffusion coefficient (MD), anisotropic fraction (FA) and appearance of deep gray matter nucleus in patients with acute carbon monoxide intoxication were analyzed. It found that the change of diffusion coefficient (ADC) and its clinical correlation with cognitive impairment were generated by carbon monoxide intoxication. RESULTS: Compared with the healthy control group, the FA values of bilateral globus pallidus, hippocampus, dater nucleus and putamen decreased, while the FA values of amygdala and thalamus had no statistical significance; the MD values and ADC values of hippocampus, globus pallidus and putamen increased, while the MD and ADC values of dater nucleus, thalamus and amygdala had no statistical significance, either. CONCLUSION: DTI is capable of sensitively reflecting the damage of gray matter nuclei caused by acute carbon monoxide intoxication and quantifying the degree of hypoxic brain damage in a certain extent, and may be related to cognitive impairment.


Assuntos
Lesões Encefálicas Difusas/diagnóstico por imagem , Intoxicação por Monóxido de Carbono/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Substância Cinzenta/diagnóstico por imagem , Doença Aguda , Adulto , Idoso , Tonsila do Cerebelo/diagnóstico por imagem , Anisotropia , Estudos de Casos e Controles , Cognição , Feminino , Globo Pálido/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Giro Para-Hipocampal/diagnóstico por imagem , Putamen/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Vigília , Adulto Jovem
3.
Medicine (Baltimore) ; 98(45): e17824, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31702636

RESUMO

The hippocampus is one of the earliest sites involved in the pathology of Alzheimer's disease (AD). Therefore, we specifically investigated the sensitivity and specificity of hippocampal volume and glucose metabolism in patients being evaluated for AD, using automated quantitative tools (NeuroQuant - magnetic resonance imaging [MRI] and Scenium - positron emission tomography [PET]) and clinical evaluation.This retrospective study included adult patients over the age of 45 years with suspected AD, who had undergone fluorodeoxyglucose positron emission tomography-computed tomography (FDG-PET-CT) and MRI. FDG-PET-CT images were analyzed both qualitatively and quantitatively. In quantitative volumetric MRI analysis, the percentage of the total intracranial volume of each brain region, as well as the total hippocampal volume, were considered in comparison to an age-adjusted percentile. The remaining brain regions were compared between groups according to the final diagnosis.Thirty-eight patients were included in this study. After a mean follow-up period of 23 ±â€Š11 months, the final diagnosis for 16 patients was AD or high-risk mild cognitive impairment (MCI). Out of the 16 patients, 8 patients were women, and the average age of all patients was 69.38 ±â€Š10.98 years. Among the remaining 22 patients enrolled in the study, 14 were women, and the average age was 67.50 ±â€Š11.60 years; a diagnosis of AD was initially excluded, but the patients may have low-risk MCI. Qualitative FDG-PET-CT analysis showed greater accuracy (0.87), sensitivity (0.76), and negative predictive value (0.77), when compared to quantitative PET analysis, hippocampal MRI volumetry, and specificity. The positive predictive value of FDG-PET-CT was similar to the MRI value.The performance of FDG-PET-CT qualitative analysis was significantly more effective compared to MRI volumetry. At least in part, this observation could corroborate the sequential hypothesis of AD pathophysiology, which posits that functional changes (synaptic dysfunction) precede structural changes (atrophy).


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Fluordesoxiglucose F18/metabolismo , Hipocampo/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Disfunção Cognitiva/metabolismo , Diagnóstico Precoce , Feminino , Glucose/metabolismo , Hipocampo/metabolismo , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Sensibilidade e Especificidade
4.
Medicine (Baltimore) ; 98(48): e18189, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770275

RESUMO

Sparse is the research on the relationship between iron metabolism and mild cognitive impairment (MCI) in adults aged over 60 years with non-alcoholic fatty liver disease (NAFLD). The soluble transferrin receptor (sTfR), serum iron (SI), serum ferritin (SF), transferrin (TRF) and hemoglobin (HB) are indicators of iron metabolism.This study examined whether iron metabolism is associated with cognitive impairment in older individuals.A cross-sectional study was held in patients from a Chinese center. Individuals with NAFLD aged over 60 years were included if they did not have excessive alcohol intake and were free of stroke or dementia. Their cognitive function was assessed by the same neurologist. 3.0T H proton magnetic resonance spectroscopy (H-MRS) was performed to evaluate the hippocampus of the participants without contraindication. t test and Chi-square test were used to analyze the data. Binary logistic regression was used for correlation analysis.Fifty four (54%) of participants were diagnosed with MCI by the psychiatrist. MCI was significantly associated with higher sTfR after adjustment of all the covariates (OR = 2.565, 95%CI: 1.334∼4.934; P = .005). No statistically significant associations were observed between MCI and age or blood glucose or choline (Cho) /creatine (Cr) of theright hippocampus head.Increased age and low levels of sTfR and HB were associated with MCI in NAFLD individuals aged over 60 years.


Assuntos
Disfunção Cognitiva , Hemoglobinas/análise , Hipocampo/diagnóstico por imagem , Ferro , Hepatopatia Gordurosa não Alcoólica , Receptores da Transferrina/sangue , Idoso , China/epidemiologia , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/metabolismo , Correlação de Dados , Estudos Transversais , Feminino , Ferritinas/análise , Humanos , Ferro/sangue , Ferro/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/psicologia , Transferrina/análise
5.
Nat Commun ; 10(1): 4900, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653847

RESUMO

The tau protein aggregates in aging and Alzheimer disease and may lead to memory loss through disruption of medial temporal lobe (MTL)-dependent memory systems. Here, we investigated tau-mediated mechanisms of hippocampal dysfunction that underlie the expression of episodic memory decline using fMRI measures of hippocampal local coherence (regional homogeneity; ReHo), distant functional connectivity and tau-PET. We show that age and tau pathology are related to higher hippocampal ReHo. Functional disconnection between the hippocampus and other components of the MTL memory system, particularly an anterior-temporal network specialized for object memory, is also associated with higher hippocampal ReHo and greater tau burden in anterior-temporal regions. These associations are not observed in the posteromedial network, specialized for context/spatial information. Higher hippocampal ReHo predicts worse memory performance. These findings suggest that tau pathology plays a role in disconnecting the hippocampus from specific MTL memory systems leading to increased local coherence and memory decline.


Assuntos
Envelhecimento/metabolismo , Córtex Entorrinal/diagnóstico por imagem , Hipocampo/diagnóstico por imagem , Emaranhados Neurofibrilares/metabolismo , Lobo Temporal/diagnóstico por imagem , Proteínas tau/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Envelhecimento/psicologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Carbolinas , Envelhecimento Cognitivo/fisiologia , Envelhecimento Cognitivo/psicologia , Meios de Contraste , Córtex Entorrinal/metabolismo , Córtex Entorrinal/fisiopatologia , Função Executiva , Feminino , Neuroimagem Funcional , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Humanos , Masculino , Memória Episódica , Memória de Curto Prazo , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Tomografia por Emissão de Pósitrons , Lobo Temporal/metabolismo , Lobo Temporal/fisiologia , Tiazóis , Adulto Jovem
6.
Nat Commun ; 10(1): 4835, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645545

RESUMO

Learning the structure of the world can be driven by reinforcement but also occurs incidentally through experience. Reinforcement learning theory has provided insight into how prediction errors drive updates in beliefs but less attention has been paid to the knowledge resulting from such learning. Here we contrast associative structures formed through reinforcement and experience of task statistics. BOLD neuroimaging in human volunteers demonstrates rigid representations of rewarded sequences in temporal pole and posterior orbito-frontal cortex, which are constructed backwards from reward. By contrast, medial prefrontal cortex and a hippocampal-amygdala border region carry reward-related knowledge but also flexible statistical knowledge of the currently relevant task model. Intriguingly, ventral striatum encodes prediction error responses but not the full RL- or statistically derived task knowledge. In summary, representations of task knowledge are derived via multiple learning processes operating at different time scales that are associated with partially overlapping and partially specialized anatomical regions.


Assuntos
Aprendizagem por Associação/fisiologia , Encéfalo/diagnóstico por imagem , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/fisiologia , Encéfalo/fisiologia , Feminino , Neuroimagem Funcional , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Humanos , Aprendizagem/fisiologia , Imagem por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiologia , Estriado Ventral/diagnóstico por imagem , Estriado Ventral/fisiologia , Adulto Jovem
7.
Postgrad Med ; 131(7): 533-538, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31478419

RESUMO

Introduction: Depression in patients with mild cognitive impairment (MCI) and dementia of the Alzheimer's type (AD) is associated with worse prognosis. Indeed, depressed MCI patients have worse cognitive performance and greater loss of gray-matter volume in several brain areas. To date, knowledge of the factors that can mitigate this detrimental effect is still limited. The aim of the present study was to understand in what way cognitive reserve/brain reserve and depression interact and are linked to regional atrophy in early stage AD. Methods: Depression was evaluated with the Patient Health Questionnaire-9 in 90 patients with early AD, and a cutoff of ≥ 5 was used to separate depressed (n = 44) from non-depressed (n = 46) patients. Each group was further stratified into high/low cognitive reserve/brain reserve. Cognitive reserve was calculated using years of education as proxy, while normalized parenchymal volumes were used to estimate brain reserve. Voxel-based morphometry was carried out to extract and analyze gray-matter maps. 2 × 2 ANCOVAs were run to test the effect of the reserve-by-depression interaction on gray matter. Age and hippocampal ratio were used as covariates. Composite indices of major cognitive domains were also analyzed with comparable models. Results: No reserve-by-depression interaction was found in the analytical models of gray matter. Depression was associated with less gray matter volume in the cerebellum and parahippocampal gyrus. The brain reserve-by-depression interaction was a significant predictor of executive functioning. Among those with high brain reserve, depressed patients had poorer executive skills. No significant results were found in association with cognitive reserve. Conclusion: These findings suggest that brain reserve may modulate the association between neurodegeneration and depression in patients with MCI and dementia of the AD type, influencing in particular executive functioning.


Assuntos
Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Reserva Cognitiva , Depressão/psicologia , Substância Cinzenta/diagnóstico por imagem , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Depressão/diagnóstico por imagem , Depressão/fisiopatologia , Feminino , Substância Cinzenta/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Giro Para-Hipocampal/diagnóstico por imagem , Giro Para-Hipocampal/patologia , Questionário de Saúde do Paciente
8.
Rinsho Shinkeigaku ; 59(9): 575-578, 2019 Sep 25.
Artigo em Japonês | MEDLINE | ID: mdl-31474643

RESUMO

A 66-year-old man was admitted to our department with anterograde amnesia. He was diagnosed with transient global amnesia (TGA) because of the symptom lasting for several hours and no abnormal findings on MRI and EEG. About a year after the episode, he recurred amnesia lasting only for 20 minutes. MRI diffusion weighted image (DWI) revealed a small hyperintense signal in the right hippocampus, while there was no abnormality on EEG. We diagnosed him with recurrent TGA. This case may be interesting in that symptom duration and MRI-DWI finding are much different between two attacks of TGA.


Assuntos
Amnésia Global Transitória/diagnóstico por imagem , Idoso , Imagem de Difusão por Ressonância Magnética , Eletroencefalografia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Masculino , Neuroimagem , Recidiva , Fatores de Tempo
9.
World Neurosurg ; 132: e759-e765, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31415886

RESUMO

OBJECTIVE: To determine postoperative long-term changes of hippocampal volume (HV) correlating with cognitive functions in patients who underwent surgery for hippocampal sclerosis with postoperative freedom from seizures. METHODS: We studied 1.5T magnetic resonance imaging before and after surgery in 24 patients (mean ± SD age, 36.9 ± 11.0 years) with hippocampal sclerosis. We performed serial magnetic resonance imaging at 6 months to 1 year, 1-2 years, 2-3 years, and 3-5 years postoperatively. We compared HVs of 24 patients with HVs of 14 age-matched control subjects. We analyzed correlations between consecutive HVs and seizure duration and age at surgery. We compared consecutive changes in HVs between dominant and nondominant hemispheres with concurrent cognitive functions. RESULTS: Preoperative HVs of unresected contralateral hippocampus were significantly smaller than HVs of control subjects (P < 0.01). Unresected contralateral HV changes compared with preoperative HVs were -3.6% ± 6.9%, -2.3% ± 8.5%, -3.6% ± 10.2% (P < 0.05), and -5.0% ± 9.5% (P < 0.05) at consecutive postoperative periods. Largest change in HVs at 3-5 years was significantly correlated with older age at surgery (P < 0.05). Unresected contralateral dominant 14 HVs remained consistently smaller than nondominant 10 HVs up to 5 years with statistical significance (P < 0.05). Verbal memory was preserved in 14 patients with unresected contralateral smaller dominant hippocampus. CONCLUSIONS: In seizure-free patients after hippocampal sclerosis resection , unresected contralateral HV significantly declined with older age at surgery. Visual memory was preserved regardless of side and volume loss. Despite significantly reduced HVs, verbal memory was preserved with the unresected contralateral dominant hippocampus. Earlier surgical intervention may have lower potential risk for memory decline secondary to postoperative HV loss.


Assuntos
Hipocampo/patologia , Hipocampo/cirurgia , Transtornos da Memória/prevenção & controle , Transtornos da Memória/psicologia , Procedimentos Neurocirúrgicos/métodos , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/psicologia , Adolescente , Adulto , Fatores Etários , Lobectomia Temporal Anterior , Criança , Dominância Cerebral , Feminino , Seguimentos , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Transtornos da Memória/etiologia , Pessoa de Meia-Idade , Testes Neuropsicológicos , Esclerose , Convulsões , Resultado do Tratamento , Adulto Jovem
10.
Transl Psychiatry ; 9(1): 191, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31431610

RESUMO

Several studies have shown that electroconvulsive therapy (ECT) results in increased hippocampal volume. It is likely that a multitude of mechanisms including neurogenesis, gliogenesis, synaptogenesis, angiogenesis, and vasculogenesis contribute to this volume increase. Neurotrophins, like vascular endothelial growth factor (VEGF) and brain-derived neurotrophic factor (BDNF) seem to play a crucial mediating role in several of these mechanisms. We hypothesized that two regulatory SNPs in the VEGF and BDNF gene influence the changes in hippocampal volume following ECT. We combined genotyping and brain MRI assessment in a sample of older adults suffering from major depressive disorder to test this hypothesis. Our results show an effect of rs699947 (in the promotor region of VEGF) on hippocampal volume changes following ECT. However, we did not find a clear effect of rs6265 (in BDNF). To the best of our knowledge, this is the first study investigating possible genetic mechanisms involved in hippocampal volume change during ECT treatment.


Assuntos
Transtorno Depressivo Maior/terapia , Eletroconvulsoterapia , Hipocampo/diagnóstico por imagem , Regiões Promotoras Genéticas , Fator A de Crescimento do Endotélio Vascular/genética , Idoso , Idoso de 80 Anos ou mais , Transtorno Depressivo Maior/diagnóstico por imagem , Transtorno Depressivo Maior/genética , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/genética , Resultado do Tratamento
11.
World Neurosurg ; 132: 314-320, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31449994

RESUMO

BACKGROUND: Whereas transient, self-limiting seizures are an infrequent but known complication of deep brain stimulation (DBS) implantation surgery, stimulation itself has occasionally been reported to result in seizure activity at delayed time points. The neural circuitry implicated in stimulation-induced seizures is unknown. CASE DESCRIPTION: A 47-year-old woman underwent chronic subcallosal cingulate DBS for treatment of refractory anorexia nervosa and experienced seizure with stimulation onset. Supratherapeutic voltage caused a generalized seizure. The patient subsequently experienced a full recovery. We reviewed the literature for other cases of delayed postoperative DBS seizures associated with stimulation. We also investigated whether the higher voltage may have recruited networks implicated in epilepsy. The supratherapeutic voltage stimulated a larger area and engaged vulnerable networks, including bilateral hippocampi, cingulate gyrus, and temporal lobes. Literature review identified 20 studies reporting delayed seizure after DBS surgery, 13 of which demonstrated a robust association with mostly nonmotor DBS stimulation. CONCLUSIONS: Nonmotor DBS targets, particularly in patients with epilepsy, may be more vulnerable to stimulation-induced seizures; as such, extra caution should be used when programming stimulation parameters at these DBS targets.


Assuntos
Anorexia Nervosa/terapia , Encéfalo/fisiopatologia , Estimulação Encefálica Profunda/efeitos adversos , Convulsões/etiologia , Anticonvulsivantes/uso terapêutico , Encéfalo/diagnóstico por imagem , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Hipocampo/diagnóstico por imagem , Hipocampo/fisiopatologia , Humanos , Lamotrigina/uso terapêutico , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Convulsões/diagnóstico por imagem , Convulsões/tratamento farmacológico , Convulsões/fisiopatologia , Lobo Temporal/diagnóstico por imagem , Lobo Temporal/fisiopatologia
12.
Zhonghua Nei Ke Za Zhi ; 58(9): 662-667, 2019 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-31461817

RESUMO

Objective: To investigate the correlation of functional connectivity (FC) and the integrity of connective fibres between hippocampus and thalamus in Alzheimer's disease(AD) and amnestic mild cognitive impairment (aMCI). Methods: Both resting-state functional magnetic resonance imaging (rs-fMRI) and diffusion tensor imaging (DTI) data of 40 AD patients, 37 aMCI patients and 41 normal control subjects matching with age and educational level were collected. These subjects were all recruited from outpatient Department of Neurology in the Second Medical Center of Chinese PLA General Hospital, as well as poster, from May 2016 to January 2018. The FC strength between bilateral hippocampus and thalamus, as well as the parameters representing integrity of connective fibres, including fractional anisotropy (FA) and mean diffusivity(MD),were analyzed. Also, the correlations between FC strength and FA or MD strength were analyzed in the study. Results: Compared to that of normal control subjects, the FC strength between billateral hippocampus and thalamus in patients with AD, aMCI were not significantly different(P>0.05). The integrity of bilateral connective fibres between hippocampus and thalamus were damaged in AD patients when compared to normal control subjects(P<0.01). A positive correlation of connective fibres integrity with FC strength between hippocampus and thalamus was found in the left side(r=0.25,P<0.05) but rather in the right side. Conclusion: In AD and aMCI patients, structural connectivity between left hippocampus and thalamus affects the functional connectivity between them.


Assuntos
Doença de Alzheimer/fisiopatologia , Amnésia/complicações , Disfunção Cognitiva/fisiopatologia , Hipocampo/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Tálamo/diagnóstico por imagem , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/patologia , Estudos de Casos e Controles , Disfunção Cognitiva/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Humanos , Imagem por Ressonância Magnética/métodos
13.
Medicine (Baltimore) ; 98(35): e16841, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464910

RESUMO

RATIONALE: Multiple primary central nervous system lymphoma (MPCNSL) is a rare disease with differential diagnosis and treatment. As the underlying pathogenesis is not yet clarified, the early-stage clinical manifestations are occult and atypical. Also, the imaging manifestations are not specific, which is challenging for the clinical diagnosis and treatment. Therefore, additional clinical research is essential to understand the etiology of the disease. PATIENT CONCERNS: A 63-year-old male patient suffered from MPCNSLs but without typical clinical manifestations. The findings of the imaging examination were as follows. Magnetic resonance imaging (MRI) showed long T1 and T2 signal shadows in the right frontal lobe, right hippocampus, right cerebellar hemisphere, and the left occipital lobe. In addition, patchy T1-enhanced signal shadows were observed in the right frontal lobe and around the midline. Frontal lesions were detected in the magnetic resonance spectroscopy (MRS), Cho peak increased, and N-acetylaspartate (NAA) peak decreased. On the other hand, in the diffusion weighted imaging (DWI), apparent dispersion coefficient (ADC) showed low-value changes and high signal changes. The positron emission tomography-computed tomography (PET-CT) displayed radioactive accumulation in the right frontal lobe. DIAGNOSIS: Multiple primary central nervous system lymphoma. INTERVENTIONS: The patient received some conservative medical treatment, but his condition continued to worsen. Finally, he received a pathological biopsy, and refused further treatment after the result was reported. OUTCOMES: The patient died 1 week after biopsy, and the course of disease was about 100 days. LESSONS: PCNSL is a primary intracranial malignancy with low incidence and a high degree of malignancy and specificity in clinical manifestations. To facilitate early clinical treatment and improve the long-term survival of patients, it is necessary to master the imaging diagnostic methods and its features. The comprehensive application of multiple imaging examinations, such as CT, MRI, PET/CT, and PET/MRI, as well as, cerebrospinal fluid cytology can greatly improve the diagnosis of PCNSL.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Imagem Multimodal/métodos , Neoplasias Primárias Múltiplas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Cerebelo/diagnóstico por imagem , Cerebelo/patologia , Imagem de Difusão por Ressonância Magnética , Evolução Fatal , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/patologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons
14.
Int J Radiat Oncol Biol Phys ; 105(4): 773-783, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31408667

RESUMO

PURPOSE: We used quantitative magnetic resonance imaging to prospectively analyze the association between microstructural damage to memory-associated structures within the medial temporal lobe and longitudinal memory performance after brain radiation therapy (RT). METHODS AND MATERIALS: Patients with a primary brain tumor receiving fractionated brain RT were enrolled on a prospective trial (n = 27). Patients underwent high-resolution volumetric brain magnetic resonance imaging, diffusion-weighted imaging, and neurocognitive testing before and 3, 6, and 12 months post-RT. Medial temporal lobe regions (hippocampus; entorhinal, parahippocampal, and temporal pole white matter [WM]) were autosegmented, quantifying volume and diffusion biomarkers of WM integrity (mean diffusivity [MD]; fractional anisotropy [FA]). Reliable change indices measured changes in verbal (Hopkins Verbal Learning Test-Revised) and visuospatial (Brief Visuospatial Memory Test-Revised [BVMT-R]) memory. Linear mixed-effects models assessed longitudinal associations between imaging parameters and memory. RESULTS: Visuospatial memory significantly declined at 6 months post-RT (mean reliable change indices, -1.3; P = .012). Concurrent chemotherapy and seizures trended toward a significant association with greater decline in visuospatial memory (P = .053 and P = .054, respectively). Higher mean dose to the left temporal pole WM was significantly associated with decreased FA (r = -0.667; P = .002). Over all time points, smaller right hippocampal volume (P = .021), lower right entorhinal FA (P = .023), greater right entorhinal MD (P = .047), and greater temporal pole MD (BVMT-R total recall, P = .003; BVMT-R delayed recall, P = .042) were associated with worse visuospatial memory. The interaction between right entorhinal MD (BVMT-R total recall, P = .021; BVMT-R delayed recall, P = .004) and temporal pole FA (BVMT-R delayed recall, P = .024) significantly predicted visuospatial memory performance. CONCLUSIONS: Brain tumor patients exhibited visuospatial memory decline post-RT. Microstructural damage to critical memory regions, including the hippocampus and medial temporal lobe WM, were associated with post-RT memory decline. The integrity of medial temporal lobe structures is critical to memory performance post-RT, representing possible avoidance targets for memory preservation.


Assuntos
Neoplasias Encefálicas/radioterapia , Irradiação Craniana/efeitos adversos , Transtornos da Memória/etiologia , Memória/efeitos da radiação , Lesões por Radiação/complicações , Lobo Temporal/efeitos da radiação , Adulto , Idoso , Agnosia/diagnóstico , Agnosia/etiologia , Anisotropia , Antineoplásicos/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Irradiação Craniana/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Fracionamento da Dose de Radiação , Córtex Entorrinal/diagnóstico por imagem , Córtex Entorrinal/efeitos da radiação , Feminino , Neuroimagem Funcional , Hipocampo/diagnóstico por imagem , Hipocampo/efeitos da radiação , Humanos , Masculino , Transtornos da Memória/diagnóstico , Rememoração Mental/efeitos dos fármacos , Rememoração Mental/efeitos da radiação , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Convulsões/complicações , Substância Branca/diagnóstico por imagem , Substância Branca/efeitos da radiação , Adulto Jovem
15.
Psychopharmacology (Berl) ; 236(12): 3451-3463, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31267156

RESUMO

RATIONALE: The N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine is known to have not only a rapid antidepressant effect but also dissociative side effects. Traxoprodil and lanicemine, also NMDA antagonists, are candidate antidepressant drugs with fewer side effects. OBJECTIVES: In order to understand their mechanism of action, we investigated the acute effects of traxoprodil and lanicemine on brain connectivity using resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: Functional connectivity (FC) alterations were examined using interregional correlation networks. Graph theoretical methods were used for whole brain network analysis. As interest in NMDAR antagonists as potential antidepressants was triggered by the antidepressant effect of ketamine, results were compared to previous findings from our ketamine studies. RESULTS: Similar to ketamine but to a smaller extent, traxoprodil increased hippocampal-prefrontal (Hc-PFC) coupling. Unlike ketamine, traxoprodil decreased connectivity within the PFC. Lanicemine had no effect on these properties. The improvement of Hc-PFC coupling corresponds well to clinical result, showing ketamine to have a greater antidepressant effect than traxoprodil, while lanicemine has a weak and transient effect. Connectivity changes overlapping between the drugs as well as alterations of local network properties occurred mostly in reward-related regions. CONCLUSION: The antidepressant effect of NMDA antagonists appears to be associated with enhanced Hc-PFC coupling. The effects on local network properties and regional connectivity suggest that improvement of reward processing might also be important for understanding the mechanisms underlying the antidepressant effects of these drugs.


Assuntos
Hipocampo/efeitos dos fármacos , Fenetilaminas/farmacologia , Piperidinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Piridinas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Recompensa , Animais , Antidepressivos/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Imagem por Ressonância Magnética/métodos , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/fisiologia
16.
J Neurol ; 266(10): 2535-2545, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31267207

RESUMO

OBJECTIVE: The aim of this study is to assess the impact of age at onset on the prognostic value of Alzheimer's biomarkers in a large sample of patients with mild cognitive impairment (MCI). METHODS: We measured Aß42, t-tau, hippocampal volume on magnetic resonance imaging (MRI) and cortical metabolism on fluorodeoxyglucose-positron emission tomography (FDG-PET) in 188 MCI patients followed for at least 1 year. We categorised patients into earlier and later onset (EO/LO). Receiver operating characteristic curves and corresponding areas under the curve (AUCs) were performed to assess and compar the biomarker prognostic performances in EO and LO groups. Linear Model was adopted for estimating the time-to-progression in relation with earlier/later onset MCI groups and biomarkers. RESULTS: In earlier onset patients, all the assessed biomarkers were able to predict cognitive decline (p < 0.05), with FDG-PET showing the best performance. In later onset patients, all biomarkers but t-tau predicted cognitive decline (p < 0.05). Moreover, FDG-PET alone in earlier onset patients showed a higher prognostic value than the one resulting from the combination of all the biomarkers in later onset patients (earlier onset AUC 0.935 vs later onset AUC 0.753, p < 0.001). Finally, FDG-PET showed a different prognostic value between earlier and later onset patients (p = 0.040) in time-to-progression allowing an estimate of the time free from disease. DISCUSSION: FDG-PET may represent the most universal tool for the establishment of a prognosis in MCI patients and may be used for obtaining an onset-related estimate of the time free from disease.


Assuntos
Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/metabolismo , Córtex Cerebral , Disfunção Cognitiva/diagnóstico , Progressão da Doença , Imagem por Ressonância Magnética/normas , Fragmentos de Peptídeos/metabolismo , Tomografia por Emissão de Pósitrons/normas , Proteínas tau/metabolismo , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Biomarcadores/metabolismo , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Conjuntos de Dados como Assunto , Feminino , Fluordesoxiglucose F18 , Seguimentos , Hipocampo/diagnóstico por imagem , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico
17.
Dev Cogn Neurosci ; 38: 100666, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31276941

RESUMO

Little is known about how childhood adversity influences the development of learning and memory and underlying neural circuits. We examined whether violence exposure in childhood influenced hippocampus-dependent associative learning and whether differences: a) were broad or specific to threat cues, and b) exhibited developmental variation. Children (n = 59; 8-19 years, 24 violence-exposed) completed an associative learning task with angry, happy, and neutral faces paired with objects during fMRI scanning. Outside the scanner, participants completed an associative memory test for face-object pairings. Violence-exposed children exhibited broad associative memory difficulties that became more pronounced with age, along with reduced recruitment of the hippocampus and atypical recruitment of fronto-parietal regions during encoding. Violence-exposed children also showed selective disruption of associative memory for threat cues regardless of age, along with reduced recruitment of the intraparietal sulcus (IPS) during encoding in the presence of threat. Broad associative learning difficulties may be a functional consequence of the toxic effects of early-life stress on hippocampal and fronto-parietal cortical development. Difficulties in the presence of threat cues may result from enhanced threat processing that disrupts encoding and short-term storage of associative information in the IPS. These associative learning difficulties may contribute to poor life outcomes following childhood violence exposure.


Assuntos
Aprendizagem por Associação/fisiologia , Sinais (Psicologia) , Exposição à Violência/psicologia , Hipocampo/diagnóstico por imagem , Hipocampo/crescimento & desenvolvimento , Adolescente , Criança , Condicionamento Clássico/fisiologia , Exposição à Violência/tendências , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Memória/fisiologia , Estimulação Luminosa/métodos , Adulto Jovem
19.
J Clin Neurosci ; 67: 68-74, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31221579

RESUMO

We sought to quantify the morphology in vivo of hippocampi in patients with drug resistant temporal lobe epilepsy (TLE) via magnetic resonance imaging (MRI), prior to temporal lobe resection, and the correlation of surface-based shape analysis of morphology and clinical cognitive function. Thirty patients with drug-resistant TLE and twenty healthy controls underwent clinical neuropsychological testing, and brain MRI at Lund University Hospital prior to hippocampal resection. A neuroradiologist categorised radiological findings into normal hippocampus, subtle changes or definite hippocampal sclerosis. We manually segmented MRI of the hippocampus of participants using ANALYZE 11.0 software; and analysed hippocampal shape using SPHARM-PDM software. For radiologist visual-ratings of definite left hippocampal sclerosis in those with left-sided TLE, hippocampal volumes were significantly smaller compared to normal controls. In right-sided TLE we found contralateral shape inflation of the left hippocampus, partially confirming previous shape analytic studies of the hippocampus in TLE. We found significant correlation of volume and surface deflation of the right hippocampus in right-sided TLE with reduced performance on the two right-lateralised visuospatial memory tests, the Rey Complex Figure Test (Immediate and Delayed recall) and the Recognition Memory Test for faces. Decreased hippocampal volume was correlated with poorer performance on these tasks. The morphology of the hippocampus can be quantified via neuroimaging shape analysis in TLE. Contralateral shape inflation of the left hippocampus in right-sided TLE is intriguing, and may result from functional compensation and/or abnormal tissue. In right-sided TLE, hippocampal structural integrity, quantified as hippocampal shape, is correlated with lateralised visuospatial function.


Assuntos
Epilepsia Resistente a Medicamentos/patologia , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Adulto , Epilepsia Resistente a Medicamentos/diagnóstico por imagem , Epilepsia do Lobo Temporal/diagnóstico por imagem , Feminino , Hipocampo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos
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