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1.
J Clin Ultrasound ; 52(5): 600-607, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581157

RESUMO

INTRODUCTION: Similarly to the ventricles, the atria are under sympathetic/parasympathetic neural regulation. Accordingly, correlations were investigated between Ewing's standard cardiovascular reflex tests (SCRTs) and three-dimensional speckle-tracking echocardiography (3DSTE)-derived right atrial (RA) volumes and strains in healthy subjects. MATERIALS AND METHODS: The study comprised 45 healthy adults, but 5 subjects were excluded due to inferior image quality for 3DSTE-derived RA assessments. The remaining 40 individuals being in sinus rhythm had a mean age of 35.1 ± 3.5 years (20 men). Two-dimensional, Doppler, 3DSTE and SCRTs were performed in all cases. RESULTS: RA maximum volume and total and passive RA stroke volumes correlated with the Valsalva ratio. Active RA stroke volume and emptying fraction showed correlations with 30/15 ratio. Peak global and mean segmental RA circumferential (CS) and longitudinal strains (LS) showed correlation with the Valsalva ratio. At atrial contraction, global RA-LS and mean segmental RA-CS showed correlations with the Valsalva ratio. Moreover, mean segmental RA-CS correlated with 30/15 ratio and mean segmental RA radial strain showed correlations with systolic blood pressure in response to standing. Autonomic neuropathy score correlated with peak global RA-LS. CONCLUSIONS: Autonomic function parameters have significant associations with specific RA functions in healthy adults, making the latter possible indicators of autonomic dysregulation.


Assuntos
Função do Átrio Direito , Ecocardiografia Tridimensional , Átrios do Coração , Humanos , Ecocardiografia Tridimensional/métodos , Masculino , Feminino , Adulto , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Função do Átrio Direito/fisiologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Sistema Nervoso Autônomo/fisiopatologia , Valores de Referência , Voluntários Saudáveis
3.
Neuroimage Clin ; 40: 103522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37820490

RESUMO

In semantic dementia (SD), asymmetric degeneration of the anterior temporal lobes is associated with loss of semantic knowledge and alterations in socioemotional behavior. There are two clinical variants of SD: semantic variant primary progressive aphasia (svPPA), which is characterized by predominant atrophy in the anterior temporal lobe and insula in the left hemisphere, and semantic behavioral variant frontotemporal dementia (sbvFTD), which is characterized by predominant atrophy in those structures in the right hemisphere. Previous studies of behavioral variant frontotemporal dementia, an associated clinical syndrome that targets the frontal lobes and anterior insula, have found impairments in baseline autonomic nervous system activity that correlate with left-lateralized frontotemporal atrophy patterns and disruptions in socioemotional functioning. Here, we evaluated whether there are similar impairments in resting autonomic nervous system activity in SD that also reflect left-lateralized atrophy and relate to diminished affiliative behavior. A total of 82 participants including 33 people with SD (20 svPPA and 13 sbvFTD) and 49 healthy older controls completed a laboratory-based assessment of respiratory sinus arrhythmia (RSA; a parasympathetic measure) and skin conductance level (SCL; a sympathetic measure) during a two-minute resting baseline period. Participants also underwent structural magnetic resonance imaging, and informants rated their current affiliative behavior on the Interpersonal Adjective Scale. Results indicated that baseline RSA and SCL were lower in SD than in healthy controls, with significant impairments present in both svPPA and sbvFTD. Voxel-based morphometry analyses revealed left-greater-than-right atrophy related to diminished parasympathetic and sympathetic outflow in SD. While left-lateralized atrophy in the mid-to-posterior insula correlated with lower RSA, left-lateralized atrophy in the ventral anterior insula correlated with lower SCL. In SD, lower baseline RSA, but not lower SCL, was associated with lower gregariousness/extraversion. Neither autonomic measure related to warmth/agreeableness, however. Through the assessment of baseline autonomic nervous system physiology, the present study contributes to expanding conceptualizations of the biological basis of socioemotional alterations in svPPA and sbvFTD.


Assuntos
Demência Frontotemporal , Humanos , Demência Frontotemporal/patologia , Lobo Temporal/patologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Sistema Nervoso Autônomo/patologia , Lobo Frontal/patologia , Atrofia/patologia , Imageamento por Ressonância Magnética
4.
Pol Arch Intern Med ; 133(12)2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-37462400

RESUMO

INTRODUCTION: Nervous system involvement is common in antineutrophil cytoplasmic antibody-associated vasculitides (AAV). While the involvement of the peripheral and central nervous system is well described, it is still unclear how and to what extent the autonomic nervous system (ANS) is affected. Functional magnetic resonance imaging (fMRI) can provide information on both structure and potential damage of the brain, as well as on the function of selected brain centers. OBJECTIVES: The aim of this study was to investigate the ANS dysfunction in AAV patients and its correlation with the results of fMRI performed during the Valsalva maneuver. PATIENTS AND METHODS: A total of 31 patients with AAV and 30 healthy controls were enrolled in the study. Each participant completed the Composite Autonomic Symptom Score (COMPASS)-31 questionnaire. MRI was performed using a 3T scanner. The participants were asked to perform the Valsalva maneuver according to the fixed protocol, and their airway pressure was monitored. During the maneuver, fMRI data were collected. The generalized least­ squares time series analysis and the region of interest (ROI) analysis were subsequently performed. RESULTS: The patients with AAV had a higher median COMPASS­ 31 score than the controls (12.86 vs 2.99, respectively; P <0.01). Structural MRI investigation did not reveal any significant differences between the groups. The brain centers involved in ANS function were detected during fMRI; however, the ROI analysis showed no differences between the study patients and controls. CONCLUSIONS: The patients with AAV reported symptoms related to the ANS dysfunction; however, no differences with respect to the functioning of the ANS brain centers were demonstrated between these patients and healthy controls in the fMRI study during the Valsalva maneuver.


Assuntos
Doenças do Sistema Nervoso Autônomo , Vasculite , Humanos , Anticorpos Anticitoplasma de Neutrófilos , Doenças do Sistema Nervoso Autônomo/diagnóstico , Sistema Nervoso Autônomo/diagnóstico por imagem , Sistema Nervoso Autônomo/fisiologia , Imageamento por Ressonância Magnética
5.
Brain Inj ; 37(10): 1187-1204, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37203154

RESUMO

BACKGROUND: Cardiovascular changes, such as altered heart rate and blood pressure, have been identified in some individuals following mild traumatic brain injury (mTBI) and may be related to disturbances of the autonomic nervous system and cerebral blood flow. METHODS: We conducted a scoping review according to PRISMA-ScR guidelines across six databases (Medline, CINAHL, Web of Science, PsychInfo, SportDiscus and Google Scholar) to explore literature examining both cardiovascular parameters and neuroimaging modalities following mTBI, with the aim of better understanding the pathophysiological basis of cardiovascular autonomic changes associated with mTBI. RESULTS: Twenty-nine studies were included and two main research approaches emerged from data synthesis. Firstly, more than half the studies used transcranial Doppler ultrasound and found evidence of cerebral blood flow impairments that persisted beyond symptom resolution. Secondly, studies utilizing advanced MRI identified microstructural injury within brain regions responsible for cardiac autonomic function, providing preliminary evidence that cardiovascular autonomic changes are a consequence of injury to these areas. CONCLUSION: Neuroimaging modalities hold considerable potential to aid understanding of the complex relationship between cardiovascular changes and brain pathophysiology associated with mTBI. However, it is difficult to draw definitive conclusions from the available data due to variability in study methodology and terminology.


Assuntos
Concussão Encefálica , Encefalopatias , Humanos , Sistema Nervoso Autônomo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Concussão Encefálica/complicações , Concussão Encefálica/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem
7.
Front Endocrinol (Lausanne) ; 12: 644826, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981285

RESUMO

Although first described over a hundred years ago, tissue optical clearing is undergoing renewed interest due to numerous advances in optical clearing methods, microscopy systems, and three-dimensional (3-D) image analysis programs. These advances are advantageous for intact mouse tissues or pieces of human tissues because samples sized several millimeters can be studied. Optical clearing methods are particularly useful for studies of the neuroanatomy of the central and peripheral nervous systems and tissue vasculature or lymphatic system. Using examples from solvent- and aqueous-based optical clearing methods, the mouse and human pancreatic structures and networks will be reviewed in 3-D for neuro-insular complexes, parasympathetic ganglia, and adipocyte infiltration as well as lymphatics in diabetes. Optical clearing with multiplex immunofluorescence microscopy provides new opportunities to examine the role of the nervous and circulatory systems in pancreatic and islet functions by defining their neurovascular anatomy in health and diabetes.


Assuntos
Imageamento Tridimensional/métodos , Pâncreas/diagnóstico por imagem , Adipócitos/patologia , Animais , Sistema Nervoso Autônomo/diagnóstico por imagem , Diabetes Mellitus/diagnóstico por imagem , Diabetes Mellitus/patologia , Gânglios/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Técnicas In Vitro , Ilhotas Pancreáticas/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Neuroanatomia , Pâncreas/irrigação sanguínea , Células de Schwann/patologia
8.
Brain ; 144(9): 2837-2851, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-33905474

RESUMO

Because of its involvement in a wide variety of cardiovascular, metabolic and behavioural functions, the hypothalamus constitutes a potential target for neuromodulation in a number of treatment-refractory conditions. The precise neural substrates and circuitry subserving these responses, however, are poorly characterized to date. We sought to retrospectively explore the acute sequelae of hypothalamic region deep brain stimulation and characterize their neuroanatomical correlates. To this end we studied-at multiple international centres-58 patients (mean age: 68.5 ± 7.9 years, 26 females) suffering from mild Alzheimer's disease who underwent stimulation of the fornix region between 2007 and 2019. We catalogued the diverse spectrum of acutely induced clinical responses during electrical stimulation and interrogated their neural substrates using volume of tissue activated modelling, voxel-wise mapping, and supervised machine learning techniques. In total 627 acute clinical responses to stimulation-including tachycardia, hypertension, flushing, sweating, warmth, coldness, nausea, phosphenes, and fear-were recorded and catalogued across patients using standard descriptive methods. The most common manifestations during hypothalamic region stimulation were tachycardia (30.9%) and warmth (24.6%) followed by flushing (9.1%) and hypertension (6.9%). Voxel-wise mapping identified distinct, locally separable clusters for all sequelae that could be mapped to specific hypothalamic and extrahypothalamic grey and white matter structures. K-nearest neighbour classification further validated the clinico-anatomical correlates emphasizing the functional importance of identified neural substrates with area under the receiving operating characteristic curves between 0.67 and 0.91. Overall, we were able to localize acute effects of hypothalamic region stimulation to distinct tracts and nuclei within the hypothalamus and the wider diencephalon providing clinico-anatomical insights that may help to guide future neuromodulation work.


Assuntos
Afeto/fisiologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Cognição/fisiologia , Estimulação Encefálica Profunda/métodos , Hipotálamo/diagnóstico por imagem , Idoso , Sistema Nervoso Autônomo/fisiologia , Temperatura Corporal/fisiologia , Eletrodos Implantados , Feminino , Humanos , Hipotálamo/fisiologia , Hipotálamo/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taquicardia/diagnóstico por imagem , Taquicardia/fisiopatologia
9.
Sci Rep ; 11(1): 5196, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664358

RESUMO

Higher arousal and cortical excitability have been observed in high hypnotizable individuals (highs) with respect to low hypnotizables (lows), which may be due to differences in the activation of ascending activating systems. The present study investigated the possible hypnotizability-related difference in the cortical noradrenergic tone sustained by the activity of the Locus Coeruleus which is strongly related to pupil size. This was measured during relaxation in three groups of participants-highs (N = 15), lows (N = 15) and medium hypnotizable individuals (mediums, N = 11)-in the time and frequency domains and through the Recurrence Quantification Analysis. ECG and Skin Conductace (SC) were monitored to extract autonomic indices of relaxation (heart interbeats intervals, parasympathetic component of heart rate variability (RMSSD) and tonic SC (MeanTonicSC). Most variables indicated that participants relaxed throughout the session. Pupil features did not show significant differences between highs, mediums and lows, except for the spectral Band Median Frequency which was higher in mediums than in lows and highs at the beginning, but not at the end of the session.Thus, the present findings of pupil size cannot account for the differences in arousal and motor cortex excitability observed between highs and lows in resting conditions.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Hipnose , Córtex Motor/fisiologia , Pupila/fisiologia , Adulto , Nível de Alerta/fisiologia , Atenção/fisiologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Neurociência Cognitiva , Estado de Consciência/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Córtex Motor/diagnóstico por imagem , Relaxamento/fisiologia , Adulto Jovem
10.
Sci Rep ; 11(1): 3025, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542260

RESUMO

Contactless measurement of heart rate variability (HRV), which reflects changes of the autonomic nervous system (ANS) and provides crucial information on the health status of a person, would provide great benefits for both patients and doctors during prevention and aftercare. However, gold standard devices to record the HRV, such as the electrocardiograph, have the common disadvantage that they need permanent skin contact with the patient. Being connected to a monitoring device by cable reduces the mobility, comfort, and compliance by patients. Here, we present a contactless approach using a 24 GHz Six-Port-based radar system and an LSTM network for radar heart sound segmentation. The best scores are obtained using a two-layer bidirectional LSTM architecture. To verify the performance of the proposed system not only in a static measurement scenario but also during a dynamic change of HRV parameters, a stimulation of the ANS through a cold pressor test is integrated in the study design. A total of 638 minutes of data is gathered from 25 test subjects and is analysed extensively. High F-scores of over 95% are achieved for heartbeat detection. HRV indices such as HF norm are extracted with relative errors around 5%. Our proposed approach is capable to perform contactless and convenient HRV monitoring and is therefore suitable for long-term recordings in clinical environments and home-care scenarios.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Frequência Cardíaca/fisiologia , Ruídos Cardíacos/fisiologia , Monitorização Fisiológica/métodos , Adulto , Sistema Nervoso Autônomo/diagnóstico por imagem , Eletrocardiografia/instrumentação , Feminino , Humanos , Interferometria/instrumentação , Masculino , Monitorização Fisiológica/instrumentação , Radar/instrumentação
11.
PLoS One ; 16(2): e0246789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33591998

RESUMO

BACKGROUND: Autonomic nervous system dysfunction is implicated in the development of hypothalamic obesity. We investigated the relationship between hypothalamic involvement (HI), central obesity, and cardiac autonomic dysfunction by assessing heart rate variability (HRV) indices in patients with childhood-onset craniopharyngioma. METHODS: A cross-sectional study of 48 patients (28 males, 10-30 years old) with hypothalamic damage after childhood-onset craniopharyngioma was performed. Postoperative HI was graded as mild (n = 19) or extensive (n = 29) on magnetic resonance imaging. Anthropometry, body composition and HRV indices including the standard deviation of all normal R-R intervals (SDNN) and total power (TP) as overall variability markers, root-mean square differences of successive R-R intervals (RMSSD) and high frequency (HF) as parasympathetic modulation markers, and low frequency (LF) as a sympathetic/sympathovagal modulation marker were measured. RESULTS: Patients with extensive HI had increased means of body mass index, waist circumference, and fat mass than those with mild HI (P < 0.05, for all). Centrally obese patients had a lower mean HF, a parasympathetic modulation marker, than centrally non-obese patients (P < 0.05). The extensive HI group had lower means of overall variability (SDNN and TP), parasympathetic modulation (HF), and sympathetic/sympathovagal modulation (LF) than the mild HI group (P < 0.05, for all). The interaction effect of HI and central obesity on HRV indices was not significant. In models adjusted for age, sex, and family history of cardiometabolic disease, the means of the overall variability indices (P < 0.05 for both SDNN and TP) and a sympathetic/sympathovagal modulation index (P < 0.05 for LF) were lower with extensive HI, without differences according to central obesity. CONCLUSIONS: The reduced HRV indices with extensive HI suggests that hypothalamic damage may contribute to cardiac autonomic dysfunction, underscoring the importance of minimizing hypothalamic damage in patients with childhood-onset craniopharyngioma.


Assuntos
Sistema Nervoso Autônomo , Índice de Massa Corporal , Craniofaringioma , Cardiopatias , Frequência Cardíaca , Imageamento por Ressonância Magnética , Obesidade Infantil , Neoplasias Hipofisárias , Adolescente , Adulto , Sistema Nervoso Autônomo/diagnóstico por imagem , Criança , Craniofaringioma/diagnóstico por imagem , Craniofaringioma/patologia , Craniofaringioma/fisiopatologia , Feminino , Cardiopatias/diagnóstico por imagem , Cardiopatias/patologia , Cardiopatias/fisiopatologia , Humanos , Masculino , Obesidade Infantil/diagnóstico por imagem , Obesidade Infantil/patologia , Obesidade Infantil/fisiopatologia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/fisiopatologia
12.
Neuroimage ; 231: 117852, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33582271

RESUMO

Regulation of the internal homeostasis is modulated by the central autonomic system. So far, the view of this system is determined by animal and human research focusing on cortical and subcortical grey substance regions. To provide an overview based on white matter architecture, we used a global tractography approach to reconstruct a network of tracts interconnecting brain regions that are known to be involved in autonomic processing. Diffusion weighted imaging data were obtained from subjects of the human connectome project (HCP) database. Resulting tracts are in good agreement with previous studies assuming a division of the central autonomic system into a cortical (CAN) and a subcortical network (SAN): the CAN consist of three subsystems that encompass all cerebral lobes and overlap within the insular cortex: a parieto-anterior-temporal pathway (PATP), an occipito-posterior-temporo-frontal pathway (OPTFP) and a limbic pathway. The SAN on the other hand connects the hypothalamus to the periaqueductal grey and locus coeruleus, before it branches into a dorsal and a lateral part that target autonomic nuclei in the rostral medulla oblongata. Our approach furthermore reveals how the CAN and SAN are interconnected: the hypothalamus can be considered as the interface-structure of the SAN, whereas the insula is the central hub of the CAN. The hypothalamus receives input from prefrontal cortical fields but is also connected to the ventral apex of the insular cortex. Thus, a holistic view of the central autonomic system could be created that may promote the understanding of autonomic signaling under physiological and pathophysiological conditions.


Assuntos
Sistema Nervoso Autônomo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Processamento de Imagem Assistida por Computador/métodos , Rede Nervosa/diagnóstico por imagem , Adulto , Sistema Nervoso Autônomo/fisiologia , Encéfalo/fisiologia , Conectoma/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Rede Nervosa/fisiologia
14.
PLoS One ; 15(12): e0243441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33332361

RESUMO

Acceleration change index (ACI) is a fast and easy to understand heart rate variability (HRV) analysis approach used for assessing cardiac autonomic control of the nervous systems. The cardiac autonomic control of the nervous system is an example of highly integrated systems operating at multiple time scales. Traditional single scale based ACI did not take into account multiple time scales and has limited capability to classify normal and pathological subjects. In this study, a novel approach multiscale ACI (MACI) is proposed by incorporating multiple time scales for improving the classification ability of ACI. We evaluated the performance of MACI for classifying, normal sinus rhythm (NSR), congestive heart failure (CHF) and atrial fibrillation subjects. The findings reveal that MACI provided better classification between healthy and pathological subjects compared to ACI. We also compared MACI with other scale-based techniques such as multiscale entropy, multiscale permutation entropy (MPE), multiscale normalized corrected Shannon entropy (MNCSE) and multiscale permutation entropy (IMPE). The preliminary results show that MACI values are more stable and reliable than IMPE and MNCSE. The results show that MACI based features lead to higher classification accuracy.


Assuntos
Fibrilação Atrial/diagnóstico , Insuficiência Cardíaca/diagnóstico , Frequência Cardíaca/fisiologia , Coração/fisiologia , Adulto , Idoso , Algoritmos , Fibrilação Atrial/fisiopatologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Sistema Nervoso Autônomo/fisiopatologia , Eletrocardiografia , Entropia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Processamento de Sinais Assistido por Computador
15.
Sci Rep ; 10(1): 13994, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814782

RESUMO

To propose a new test to evaluate the autonomic nervous system in patients with syncope: Multimodal Monitoring for Diagnosis of Dysautonomia (MMDD). We included 21 patients with syncope (16 female, 6 male, mean age 43.5 years) and 21 with no-syncope subjects (15 female, 7 male, mean age 45.1 years) to perform a test of nine 2-min stages: four while resting and four during active testing of autonomic response. Transcranial-Doppler, electrocardiogram, and photoplethysmography blood pressure pulse-to-pulse monitoring, allow registering six variables from the Middle Cerebral Artery and four from the Cardiovascular System. We analyze each variable's mean differences in each stage and its change when they pass from one stage to another with the T and Z tests. To understand the significance of the change, we use a logistic regression model for a certain subgroup of variables. Since we have a small dataset, we use the bootstrap technique to infer the general behavior that characterizes a syncope. Our data confirm differences between syncope and non-syncope patients during MMDD stress stages 2, 4, 6 and 8. Bootstrap and multivariate logistic regression allow us to identify which sets of variables in each of these stages of the MMDD are sufficiently sensitive to recognizing syncope. MMDD protocol can recognize a syncope patient with some confidence by detecting subtle changes in the autonomic nervous system. This protocol encourages us to continue to study the effectiveness of MMDD protocol allowing a new approach to future research.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea/fisiologia , Sistema Cardiovascular/fisiopatologia , Disautonomias Primárias/fisiopatologia , Síncope/fisiopatologia , Adulto , Sistema Nervoso Autônomo/diagnóstico por imagem , Sistema Cardiovascular/diagnóstico por imagem , Eletrocardiografia/métodos , Estudos de Viabilidade , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Disautonomias Primárias/diagnóstico , Disautonomias Primárias/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Síncope/diagnóstico , Síncope/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos
16.
Sci Rep ; 10(1): 11661, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669640

RESUMO

Mild cognitive impairment (MCI) is a heterogeneous syndrome with two main clinical subtypes, amnestic (aMCI) and non-amnestic (naMCI). The analysis of heart rate variability (HRV) is a tool to assess autonomic function. Cognitive and autonomic processes are linked via the central autonomic network. Autonomic dysfunction entails several adverse outcomes. However, very few studies have investigated autonomic function in MCI and none have considered MCI subtypes or the relationship of HRV indices with different cognitive domains and structural brain damage. We assessed autonomic function during an active orthostatic challenge in 253 oupatients aged ≥ 65, [n = 82 aMCI, n = 93 naMCI, n = 78 cognitively normal (CN), neuropsychologically tested] with power spectral analysis of HRV. We used visual rating scales to grade cerebrovascular burden and hippocampal/insular atrophy (HA/IA) on neuroimaging. Only aMCI showed a blunted response to orthostasis. Postural changes in normalised low frequency (LF) power and in the LF to high frequency ratio correlated with a memory test (positively) and HA/IA (negatively) in aMCI, and with attention/executive function tests (negatively) and cerebrovascular burden (positively) in naMCI. These results substantiate the view that the ANS is differentially impaired in aMCI and naMCI, consistently with the neuroanatomic substrate of Alzheimer's and small-vessel subcortical ischaemic disease.


Assuntos
Amnésia/fisiopatologia , Sistema Nervoso Autônomo/fisiopatologia , Córtex Cerebral/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Coração/fisiopatologia , Hipocampo/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Amnésia/diagnóstico por imagem , Atenção/fisiologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Estudos Transversais , Tontura/diagnóstico por imagem , Tontura/fisiopatologia , Função Executiva/fisiologia , Feminino , Coração/diagnóstico por imagem , Frequência Cardíaca/fisiologia , Hipocampo/diagnóstico por imagem , Humanos , Masculino , Memória/fisiologia , Neuroimagem , Testes Neuropsicológicos , Equilíbrio Postural/fisiologia , Índice de Gravidade de Doença
17.
PLoS One ; 15(4): e0232475, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353033

RESUMO

BACKGROUND: Myalgic encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS) is a multi-system illness characterised by a diverse range of debilitating symptoms including autonomic and cognitive dysfunction. The pathomechanism remains elusive, however, neurological and cognitive aberrations are consistently described. This systematic review is the first to collect and appraise the literature related to the structural and functional neurological changes in ME/CFS patients as measured by neuroimaging techniques and to investigate how these changes may influence onset, symptom presentation and severity of the illness. METHODS: A systematic search of databases Pubmed, Embase, MEDLINE (via EBSCOhost) and Web of Science (via Clarivate Analytics) was performed for articles dating between December 1994 and August 2019. Included publications report on neurological differences in ME/CFS patients compared with healthy controls identified using neuroimaging techniques such as magnetic resonance imaging, positron emission tomography and electroencephalography. Article selection was further refined based on specific inclusion and exclusion criteria. A quality assessment of included publications was completed using the Joanna Briggs Institute checklist. RESULTS: A total of 55 studies were included in this review. All papers assessed neurological or cognitive differences in adult ME/CFS patients compared with healthy controls using neuroimaging techniques. The outcomes from the articles include changes in gray and white matter volumes, cerebral blood flow, brain structure, sleep, EEG activity, functional connectivity and cognitive function. Secondary measures including symptom severity were also reported in most studies. CONCLUSIONS: The results suggest widespread disruption of the autonomic nervous system network including morphological changes, white matter abnormalities and aberrations in functional connectivity. However, these findings are not consistent across studies and the origins of these anomalies remain unknown. Future studies are required confirm the potential neurological contribution to the pathology of ME/CFS.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Síndrome de Fadiga Crônica/fisiopatologia , Neuroimagem , Substância Branca/fisiopatologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Síndrome de Fadiga Crônica/diagnóstico , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiopatologia , Humanos , Índice de Gravidade de Doença , Substância Branca/diagnóstico por imagem
18.
Psychiatry Res Neuroimaging ; 300: 111079, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283474

RESUMO

Heart rate variability (HRV), a measurement of autonomic nervous system (ANS) activity, has been found reduced in schizophrenia. The anterior cingulate cortex (ACC), which is important in regulating the ANS, is structurally and functionally affected in schizophrenia. We investigate the relationship between HRV and functional and structural connectivity of the ACC in patients with schizophrenia and healthy controls. Ten patients with a diagnosis of schizophrenia and ten healthy controls were recruited. Heart rate was monitored in a naturalistic out-of-clinic setting. Magnetic resonance imaging (MRI) was performed, including resting-state functional MRI and diffusion tensor imaging. Patients with schizophrenia had significantly lower HRV compared to controls. A positive correlation between ACC connectivity with the bilateral cerebellum and HRV was found in the patients. HRV was also positively correlated with amplitude of low frequency fluctuations (ALFF) in the cerebellum, and with axial diffusivity in the middle cerebellar peduncle, in the patients. There was a significant negative relationship between antipsychotic medication dosage, HRV and all neuroimaging measures related to HRV. We conclude that ACC connectivity seems to be affected in schizophrenia, both structurally and functionally, and that the ACC-cerebellum connectivity, as well as cerebellar function, is associated with ANS regulation in patients with schizophrenia.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Frequência Cardíaca/fisiologia , Rede Nervosa/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Antipsicóticos/uso terapêutico , Sistema Nervoso Autônomo/diagnóstico por imagem , Estudos de Casos e Controles , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Imagem de Tensor de Difusão , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico
19.
PLoS One ; 15(3): e0229860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32134983

RESUMO

PURPOSE: We have evaluated the clinical significance of the washout rate (WR) on I-123 MIBG scans through the analysis of the relationship between the I-123 MIBG scans and autonomic status in patients with Parkinson's disease (PD). MATERIALS AND METHODS: Sixty patients with clinical PD who had decreased HMR were enrolled. An autonomic symptom was evaluated using a head-up tilt test and the Composite Autonomic Severity Score (CASS). An I-123 MIBG scan and F-18 FP-CIT positron emission tomography (PET) were performed. All of the patients were classified into three groups according to the WR. The differences in patient characteristics and the imaging parameters among the three groups were evaluated, and a correlation analysis was also performed. RESULTS: The frequency of orthostatic hypotension was significantly different among the three groups. The difference in systolic pressure (dSysPr) and the difference in diastolic pressure (dDiaPr) of group 3 was significantly larger than those of groups 1 and 2. From the correlation analysis, it can be seen that age, Hoehn and Yahr (H&Y) stage, dSysPr, and dDiaPr had a weak positive correlation with the WR. The total CASS score was significantly higher in group 3 compared with groups 1 and 2. The WR had a moderate positive correlation with the cardiosympathetic score and the total CASS score. CONCLUSION: The WR is related to autonomic dysfunction. An I-123 MIBG cardiac scan is considered to be a good method to evaluate not only the differential diagnosis of Parkinson's disease but also the degree of autonomic dysfunction.


Assuntos
3-Iodobenzilguanidina/administração & dosagem , Sistema Nervoso Autônomo/diagnóstico por imagem , Radioisótopos do Iodo/administração & dosagem , Doença de Parkinson/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/administração & dosagem , 3-Iodobenzilguanidina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Feminino , Radioisótopos de Flúor/administração & dosagem , Radioisótopos de Flúor/metabolismo , Coração/diagnóstico por imagem , Humanos , Hipotensão Ortostática/diagnóstico , Radioisótopos do Iodo/metabolismo , Masculino , Mediastino/diagnóstico por imagem , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/metabolismo , Estudos Retrospectivos , Tropanos/administração & dosagem , Tropanos/metabolismo
20.
Acta Radiol ; 61(12): 1668-1676, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32212832

RESUMO

BACKGROUND: Treatment of female pelvic malignancies often causes pelvic nerve damage. Magnetic resonance (MR) neurography mapping the female pelvic innervation could aid in treatment planning. PURPOSE: To depict female autonomic and somatic pelvic innervation using a modified 3D NerveVIEW sequence. MATERIAL AND METHODS: Prospective study in 20 female volunteers (n = 6 normal, n = 14 cervical pathology) who underwent a modified 3D short TI inversion recovery (STIR) turbo spin-echo (TSE) scan with a motion-sensitive driven equilibrium (MSDE) preparation radiofrequency pulse and flow compensation. Modifications included offset independent trapezoid (OIT) pulses for inversion and MSDE refocusing. Maximum intensity projections (MIP) were evaluated by two observers (Observer 1, Observer 2); image quality was scored as 2 = high, 1 = medium, or 0 = low with the sciatic nerve serving as a reference. Conspicuity of autonomic superior (SHP) and bilateral inferior hypogastric plexuses (IHP), hypogastric nerves, and somatic pelvic nerves (sciatic, pudendal) was scored as 2 = well-defined, 1 = poorly defined, or 0 = not seen, and inter-observer agreement was determined. RESULTS: Images were of medium to high quality according to both observers agreeing in 15/20 (75%) of individuals. SHP and bilateral hypogastric nerves were seen in 30/60 (50%) of cases by both observers. Bilateral IHP was seen in 85% (34/40) by Observer 1 and in 75% (30/40) by Observer 2. Sciatic nerves were well identified in all cases, while pudendal nerves were seen bilaterally by Observer 1 in 65% (26/40) and by Observer 2 in 72.5% (29/40). Agreement between observers for scoring nerve conspicuity was in the range of 60%-100%. CONCLUSION: Modified 3D NerveVIEW renders high-quality images of the female autonomic and pudendal nerves.


Assuntos
Sistema Nervoso Autônomo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Pelve/inervação , Nervo Pudendo/diagnóstico por imagem , Adulto , Estudos de Viabilidade , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem
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