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2.
Adv Exp Med Biol ; 1232: 3-9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893387

RESUMO

Neonates with hypoxic-ischaemic (HI) brain injury were monitored using a broadband near-infrared spectroscopy (NIRS) system in the neonatal intensive care unit. The aim of this work is to use the NIRS cerebral oxygenation data (HbD = oxygenated-haemoglobin - deoxygenated-haemoglobin) combined with arterial saturation (SaO2) from pulse oximetry to calculate cerebral blood flow (CBF) based on the oxygen swing method, during spontaneous desaturation episodes. The method is based on Fick's principle and uses HbD as a tracer; when a sudden change in SaO2 occurs, the change in HbD represents a change in tracer concentration, and thus it is possible to estimate CBF. CBF was successfully calculated with broadband NIRS in 11 HIE infants (3 with severe injury) for 70 oxygenation events on the day of birth. The average CBF was 18.0 ± 12.7 ml 100 g-1 min-1 with a range of 4 ml 100 g-1 min-1 to 60 ml 100 g-1 min-1. For infants with severe HIE (as determined by magnetic resonance spectroscopy) CBF was significantly lower (p = 0.038, d = 1.35) than those with moderate HIE on the day of birth.


Assuntos
Lesões Encefálicas , Encéfalo , Circulação Cerebrovascular , Oximetria , Oxigênio , Espectroscopia de Luz Próxima ao Infravermelho , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Humanos , Recém-Nascido , Oximetria/instrumentação , Oximetria/métodos , Oxigênio/metabolismo
3.
Adv Exp Med Biol ; 1232: 47-53, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893393

RESUMO

Cerebrovascular reactivity (CVR) is a compensatory mechanism where blood vessels dilate in response to a vasodilatory stimulus, and is a biomarker of vascular reserve and microvascular health. Impaired CVR indicates microvascular hemodynamic dysfunction, which is implicated in traumatic brain injury (TBI) and associated with long-term neurological deficiency. Recently we have shown that anodal transcranial direct current stimulation (tDCS) caused prolonged dilatation of cerebral arterioles that increased brain microvascular flow and tissue oxygenation in traumatized mouse brain and was associated with neurologic improvement. Here we evaluate the effects of tDCS on impaired CVR and microvascular cerebral blood flow (mCBF) regulation after TBI. TBI was induced in mice by controlled cortical impact (CCI). Cortical microvascular tone, mCBF, and tissue oxygen supply (by nicotinamide adenine dinucleotide, NADH) were measured by two-photon laser scanning microscopy before and after anodal tDCS (0.1 mA/15 min). CVR and mCBF regulation were evaluated by measuring changes in arteriolar diameters and NADH during hypercapnia test before and after tDCS. Transient hypercapnia was induced by 60-s increase of CO2 concentration in the inhalation mixture to 10%. As previously, anodal tDCS dilated arterioles which increased arteriolar blood flow volume that led to an increase in capillary flow velocity and the number of functioning capillaries, thereby improving tissue oxygenation in both traumatized and sham animals. In sham mice, transient hypercapnia caused transient dilatation of cerebral arterioles with constant NADH, reflecting intact CVR and mCBF regulation. In TBI animals, arteriolar dilatation response to hypercapnia was diminished while the NADH level increased (tissue oxygen supply decreased), reflecting impaired CVR and mCBF regulation. Anodal tDCS enhanced reactivity in parenchymal arterioles in both groups (especially in TBI mice) and restored CVR thereby prevented the reduction in tissue oxygen supply during hypercapnia. CVR has been shown to be related to nitric oxide elevation due to nitric oxide synthases activation, which can be sensitive to the electrical field induced by tDCS.


Assuntos
Lesões Encefálicas Traumáticas , Circulação Cerebrovascular , Estimulação Transcraniana por Corrente Contínua , Animais , Encéfalo/patologia , Lesões Encefálicas Traumáticas/terapia , Circulação Cerebrovascular/fisiologia , Hipercapnia , Camundongos
4.
Adv Exp Med Biol ; 1232: 55-62, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893394

RESUMO

The aim was to investigate the feasibility of simultaneous comparison of cerebral circulation in major vessels and microvasculature in patients suffering traumatic brain injury (TBI) with or without intracranial hematomas (IH). METHODS: 170 patients were divided into two groups: Group 1 - diffuse TBI (75 patients); and Group 2 - TBI with IH (95 patients: 18 epidural, 65 subdural and 12 multiple). Perfusion computed tomography (PCT) for assessment of volumetric cerebral blood flow (CBF) was done 2-15 days after admission to hospital. Simultaneous assessment of cerebral blood flow velocity (CBFV) in both middle cerebral arteries was done by transcranial Doppler. RESULTS: In patients with diffuse TBI, CBF had statistically valid correlations with CBFV (r = 0.28, p = 0.0149 on the left side; r = 0.382, p = 0.00075 on the right side). In patients with TBI and IH, the analysis did not reveal any reliable correlations between the CBFV and CBF velocity in the temporal lobes, either on the side of the removed IH or on the opposite side. CONCLUSION: The greatest linear correlation was noted in patients with diffuse TBI without the development of a coarse shift of the midline structures and dislocation syndrome. This correlation decreases with the increase in injury severity and development of secondary complications in the acute period, which probably reflects impairment of the coupling of oxygen consumption by brain tissue and cerebral microcirculation.


Assuntos
Lesões Encefálicas Traumáticas , Circulação Cerebrovascular , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana , Velocidade do Fluxo Sanguíneo , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Humanos , Artéria Cerebral Média/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Ultrassonografia Doppler Transcraniana/normas
5.
Adv Exp Med Biol ; 1232: 69-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893396

RESUMO

We investigated the relationship between cerebral oxygenation (COX) and skin blood flow (SkBF) at the left frontal lobes of 10 healthy young men during progressive hypoxia (∼ -1 h at each of 21%, 18%, 15%, and 12% of inspired oxygen [FiO2]). Acute hypotension was manipulated by a thigh-cuff-release technique, where a pressure of 220 mmHg was applied at both thigh muscles for 3 min and the cuff was immediately released to induce acute hypotension. While the resting baseline for COX before the thigh-cuff release manipulation decreased gradually with the reduction of FiO2 (P < 0.05), the resting baseline for SkBF, mean arterial blood pressure (MAP), and cutaneous vascular conductance (CVC) were unaffected by FiO2 (P > 0.05). The acute hypotension that was induced by the thigh-cuff release decreased COX, SkBF, MAP, and CVC; thereafter, these values recovered toward their baseline values. During the hypotension phase, while the time to the nadir values for COX slowed progressively with reductions in FiO2 (P < 0.05), those for SkBF, MAP, and CVC were unaffected by FiO2 (P > 0.05). These results suggest that COX may not be associated with SkBF for the protocol or with the subjects in the present study.


Assuntos
Circulação Cerebrovascular , Lobo Frontal , Hipotensão , Pele , Adulto , Velocidade do Fluxo Sanguíneo , Lobo Frontal/fisiologia , Hemodinâmica , Humanos , Hipotensão/fisiopatologia , Masculino , Pele/irrigação sanguínea , Adulto Jovem
6.
Adv Exp Med Biol ; 1232: 77-83, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893397

RESUMO

Instantaneous orthostatic hypotension (INOH) is one of the main types of orthostatic dysregulation in children and adolescents. In patients with INOH arterial pressure drops considerably after active standing and is slow to recover. We investigated changes in cerebral oxygenation in the bilateral prefrontal cortex during an active standing test in juvenile INOH patients to evaluate changes in cerebral oxygen metabolism. We enrolled 82 INOH patients (mean age 13.8 ± 2.2 years, 52 mild and 30 severe patients) at Nihon University Itabashi Hospital from October 2013 to April 2018. We measured cerebral oxygenated hemoglobin, deoxygenated hemoglobin, and total hemoglobin levels in the bilateral prefrontal cortex using near-infrared spectroscopy during an active standing test. In severe INOH patients, cerebral oxygenation of the right prefrontal cortex remained constant when blood pressure dropped; however, de-oxy-Hb significantly increased. These findings confirm that there is asymmetrical autoregulation between the right and left prefrontal cortex.


Assuntos
Circulação Cerebrovascular , Hipotensão Ortostática , Adolescente , Circulação Cerebrovascular/fisiologia , Criança , Homeostase , Humanos , Hipotensão Ortostática/fisiopatologia , Oxiemoglobinas , Espectroscopia de Luz Próxima ao Infravermelho
7.
Adv Exp Med Biol ; 1232: 85-90, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893398

RESUMO

Delayed orthostatic hypotension (OH) is a minor subset of orthostatic dysregulation (OD). Cerebral blood oxygenation in juvenile patients with delayed OH has not been studied. We investigated the bilateral changes in cerebral oxygenation in the prefrontal cortex during an active standing test in 23 juvenile patients with delayed OH using near-infrared spectroscopy (NIRS). We measured the oxy-Hb, deoxy-Hb, and total-Hb during the active standing test. Four observations were made during the test: t1 in a resting supine position, t2 when maintaining blood pressure, and the remaining two (t3, t4) during hypotension. The concentration of oxy-Hb significantly decreased prior to satisfying the diagnostic criteria of delayed OH after standing and did not change thereafter. The concentration of deoxy-Hb increased gradually during the measurement periods. In addition, total-Hb increased from t2 to t3. There was no significant difference in the change in each Hb parameter between the left and right cerebral hemispheres. Our results indicate that NIRS parameters are more sensitive than blood pressure for the interpretation of cerebral autoregulation in juvenile patients with delayed OH.


Assuntos
Sistema Cardiovascular , Circulação Cerebrovascular , Hipotensão Ortostática , Oxigênio , Posição Ortostática , Adolescente , Pressão Sanguínea , Circulação Cerebrovascular/fisiologia , Humanos , Hipotensão Ortostática/sangue , Hipotensão Ortostática/diagnóstico , Oxigênio/sangue , Espectroscopia de Luz Próxima ao Infravermelho
8.
Adv Exp Med Biol ; 1232: 285-290, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893422

RESUMO

In neonatal intensive care units (NICUs), 87.5% of alarms by the monitoring system are false alarms, often caused by the movements of the neonates. Such false alarms are not only stressful for the neonates as well as for their parents and caregivers, but may also lead to longer response times in real critical situations. The aim of this project was to reduce the rates of false alarms by employing machine learning algorithms (MLA), which intelligently analyze data stemming from standard physiological monitoring in combination with cerebral oximetry data (in-house built, OxyPrem). MATERIALS & METHODS: Four popular MLAs were selected to categorize the alarms as false or real: (i) decision tree (DT), (ii) 5-nearest neighbors (5-NN), (iii) naïve Bayes (NB) and (iv) support vector machine (SVM). We acquired and processed monitoring data (median duration (SD): 54.6 (± 6.9) min) of 14 preterm infants (gestational age: 26 6/7 (± 2 5/7) weeks). A hybrid method of filter and wrapper feature selection generated the candidate subset for training these four MLAs. RESULTS: A high specificity of >99% was achieved by all four approaches. DT showed the highest sensitivity (87%). The cerebral oximetry data improved the classification accuracy. DISCUSSION & CONCLUSION: Despite a (as yet) low amount of data for training, the four MLAs achieved an excellent specificity and a promising sensitivity. Presently, the current sensitivity is insufficient since, in the NICU, it is crucial that no real alarms are missed. This will most likely be improved by including more subjects and data in the training of the MLAs, which makes pursuing this approach worthwhile.


Assuntos
Unidades de Terapia Intensiva Neonatal , Terapia Intensiva Neonatal , Aprendizado de Máquina , Monitorização Fisiológica , Oximetria , Teorema de Bayes , Circulação Cerebrovascular , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Terapia Intensiva Neonatal/métodos , Monitorização Fisiológica/métodos , Oximetria/métodos , Oximetria/normas
9.
Adv Exp Med Biol ; 1232: 299-306, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893424

RESUMO

Hypoxic ischemic encephalopathy (HIE) is a significant cause of death and neurological disability in newborns. Therapeutic hypothermia at 33.5 °C is one of the most common treatments in HIE and generally improves outcome; however 45-55% of injuries still result in death or severe neurodevelopmental disability. We have developed a systems biology model of cerebral oxygen transport and metabolism to model the impact of hypothermia on the piglet brain (the neonatal preclinical animal model) tissue physiology. This computational model is an extension of the BrainSignals model of the adult brain. The model predicts that during hypothermia there is a 5.1% decrease in cerebral metabolism, 1.1% decrease in blood flow and 2.3% increase in cerebral tissue oxygenation saturation. The model can be used to simulate effects of hypothermia on the brain and to help interpret bedside recordings.


Assuntos
Circulação Cerebrovascular , Cérebro , Hipotermia , Modelos Biológicos , Animais , Animais Recém-Nascidos , Circulação Cerebrovascular/fisiologia , Cérebro/metabolismo , Simulação por Computador , Humanos , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Suínos
10.
Adv Exp Med Biol ; 1232: 323-329, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893427

RESUMO

Recent guidelines on cardiopulmonary resuscitation (CPR) have stressed the necessity to improve the quality of CPR. Our previous studies demonstrated the usefulness of monitoring cerebral blood oxygenation (CBO) during CPR by near-infrared spectroscopy (NIRS). The present study evaluates whether the NIRO-CCR1, a new NIRS device, is as useful in the clinical setting as the NIRO-200NX. We monitored CBO in 20 patients with cardiac arrest by NIRS. On the arrival of patients at the emergency department, the attending physician immediately assessed whether the patient was eligible for this study after conventional advanced life support and, if eligible, measured CBO in the frontal lobe by NIRS. We found that in all patients, the cerebral blood flow waveform was in synchrony with the chest compressions. Moreover, the tissue oxygenation index increased following cardiopulmonary bypass (CPB) in patients undergoing CPB, including one patient in whom CBO was monitored using the NIRO-CCR1. In addition, although the NIRO-CCR1 could display the pulse rate (Tempo) in real time, Tempo was not always detected, despite detection of the cerebral blood flow waveform. This suggested that chest compressions may not have been effective, indicating that the NIRO-CCR1 also seems useful to assess the quality of CPR. This study suggests that the NIRO-CCR1 can measure CBO during CPR in patients with cardiac arrest as effectively as the NIRO-200NX; in addition, the new NIRO-CCR1 may be even more useful, especially in prehospital fields (e.g. in an ambulance), since it is easy to carry.


Assuntos
Reanimação Cardiopulmonar , Circulação Cerebrovascular , Parada Cardíaca , Monitorização Fisiológica , Oximetria , Espectroscopia de Luz Próxima ao Infravermelho , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/normas , Oximetria/instrumentação , Oximetria/normas , Projetos Piloto , Espectroscopia de Luz Próxima ao Infravermelho/instrumentação , Espectroscopia de Luz Próxima ao Infravermelho/normas
11.
Medicine (Baltimore) ; 99(4): e18998, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977916

RESUMO

The causes for falls in the elderly are varied, and visual spatial neglect could be 1 contributing factor. Further, the presence of a carotid artery plaque, especially on the right side, might influence the visual spatial attention of the elderly.Our aim was to identify the intrinsic association between carotid plaques and lateralization of spatial attention in the elderly. Further, we sought to understand and potentially prevent the consequences of unilateral spatial neglect such as injury from falls.Participants aged 64 to 93 years were divided into a group with carotid artery plaque(s) of the right side or both sides (BOTH, n = 38; and 9/ 38 were right side only) and a group without right-side carotid artery plaque(s) (LEFT, n = 53). Participants were asked to perform a line bisection task and undergo doppler ultrasonography examinations.Contrary to expectations, compared to LEFT, the mean index and net scores of the line bisection errors in BOTH were significantly less leftward, but the mean diameter of the right-side common carotid artery in BOTH was significantly larger.Our results indicate that the presence of carotid plaque(s) might be linked to increased risk of falls in the elderly. The attenuated spatial neglect in participants with right-side carotid artery plaque(s) might be due to compensatory carotid artery dilatation.


Assuntos
Acidentes por Quedas , Estenose das Carótidas/complicações , Transtornos da Percepção/complicações , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Primitiva/patologia , Artéria Carótida Interna/patologia , Estudos de Casos e Controles , Circulação Cerebrovascular/fisiologia , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Fatores de Risco
12.
World Neurosurg ; 133: e558-e566, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31562963

RESUMO

OBJECTIVE: In pediatric patients with moyamoya disease, the pathophysiology of transient neurological deficits and the clinical features of perioperative cerebral blood flow (CBF) changes are unclear. The purpose of this study was to investigate the risk factors of postoperative transient neurological deficits and identify predictors of perioperative CBF changes. METHODS: This retrospective study included 42 surgical procedures in 28 pediatric patients who underwent surgical revascularization for moyamoya disease, including encephalo-myo-synangiosis (EMS) with or without superficial temporal artery-middle cerebral artery (MCA) anastomosis. Magnetic resonance images and single photon emission computed tomography results were obtained. Brain compression by EMS was also checked in fluid attenuated inversion recovery images. Using single photon emission computed tomography, CBF was measured at each anterior and posterior part of the MCA region. RESULTS: Postoperative transient neurological deficits were observed in 12 (28.6%) out of 42 surgical procedures. Brain compression by EMS was a significant risk for transient neurological deficits (P = 0.009). The postoperative CBF in the anterior region increased in 9 cases (21.4%) and decreased in 10 cases (23.8%); in the posterior region, it increased in 12 cases (28.6%) and decreased in 10 cases (23.8%). Preoperative CBF of the anterior region was significantly related to both perioperative CBF changes in the MCA regions (anterior part, P = 0.004; posterior part, P = 0.025). CONCLUSIONS: Brain compression by EMS is a risk factor for postoperative transient neurological deficits in pediatric patients with moyamoya disease, and preoperative CBF of the anterior MCA region could predict perioperative CBF change in the MCA regions.


Assuntos
Revascularização Cerebral/efeitos adversos , Revascularização Cerebral/métodos , Doença de Moyamoya/cirurgia , Complicações Pós-Operatórias/etiologia , Circulação Cerebrovascular/fisiologia , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco
13.
World Neurosurg ; 133: e522-e528, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31550537

RESUMO

OBJECTIVE: We aimed to compare flat detector computed tomography cerebral blood volume (FD-CBV) imaging to single-photon emission computed tomography (SPECT) as an adjunctive technique during balloon test occlusion (BTO) in patients with intracranial aneurysms or tumors. METHODS: Twelve patients who underwent SPECT (99mTc-ethyl cysteinate dimer) and FD-CBV imaging during BTO were enrolled. Color-coded cerebral blood flow (CBF) images and color-coded FD-CBV images were generated and visually inspected whether there were asymmetries between the ipsilateral and contralateral cerebral hemispheres. Region of interest measurements were performed on the color-coded images at the same locations for both modalities. The mean interhemispheric region of interest ratios were calculated, and the ratio between these were estimated using linear regression models. RESULTS: Ten patients had no symptoms during BTO. Two patients developed subtle but inconclusive neurologic changes approximately 10 minutes after balloon inflation; their images showed asymmetric color-coded images with decreased CBF and FD-CBV in the ipsilateral hemisphere. The mean interhemispheric ratio of CBF was significantly smaller in patients with subtle changes than in those without (0.84 vs. 0.98; P < 0.001). Similarly, the mean interhemispheric ratio of FD-CBV was significantly smaller in patients with subtle changes than in those without (0.88 vs. 1.06; P = 0.01). No patient showed increased CBF or FD-CBV in the ipsilateral hemisphere. CONCLUSIONS: The patients with decreased CBF on SPECT also showed decreased FD-CBV in the ipsilateral hemisphere. FD-CBV imaging may be useful as an adjunctive technique for BTO before potential therapeutic carotid artery occlusion.


Assuntos
Arteriopatias Oclusivas/diagnóstico por imagem , Oclusão com Balão/métodos , Doenças das Artérias Carótidas/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Arteriopatias Oclusivas/cirurgia , Doenças das Artérias Carótidas/cirurgia , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Masculino , Neuroimagem/métodos
14.
World Neurosurg ; 133: e89-e96, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31479795

RESUMO

OBJECTIVE: To evaluate the feasibility to treat complex internal carotid aneurysms by superficial temporal artery trunk-radial artery-middle cerebral artery (STAT-RA-MCA) bypass combined with balloon occlusion of internal carotid artery. METHODS: Postoperative clinical symptoms, the patency of bridge vessels (radial artery graft [RAG]), STAT and RAG diameters, RAG flow, cerebral blood flow (CBF), and mean transit time (MTT) were observed in 14 cases. Their correlations were analyzed. RESULTS: Except 1 case, RAG was patent in 13 cases. Glasgow Outcome Scale score was 4 in one case and 5 in 13 cases. In the 13 cases with postoperative RAG patency, the mean diameter of STAT increased from 2.1 mm before operation to 3.0 mm on the first day after operation; the mean diameter of RAG was 3.7 mm on the first day after operation. In 3 of the 13 cases, STAT and RAG diameters further increased to 4.0 mm and 4.7 mm, respectively, 3 months after operation. There was a positive correlation between STAT and RAG diameters (P = 0.0005). The STAT (P < 0.0001, P < 0.0001) and RAG (P < 0.0001, P = 0.0042) diameters were positively correlated with RAG flow and CBF, but the STAT (r2 = 0.762, P < 0.0001) and RAG (r2 = 0.54, P = 0.0042) diameters were negatively correlated with MTT. CONCLUSIONS: STAT-RA-MCA bypass combined with balloon occlusion of internal carotid artery is feasible for the treatment of complex internal carotid aneurysms.


Assuntos
Oclusão com Balão , Artéria Carótida Interna/cirurgia , Revascularização Cerebral/métodos , Aneurisma Intracraniano/cirurgia , Artéria Cerebral Média/cirurgia , Artéria Radial/transplante , Artérias Temporais/cirurgia , Adulto , Idoso , Aneurisma Roto/etiologia , Aneurisma Roto/cirurgia , Circulação Cerebrovascular , Transtornos Cognitivos/etiologia , Estudos de Viabilidade , Feminino , Hemiplegia/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Hemorragia Subaracnóidea/etiologia , Adulto Jovem
15.
Acta Neurochir Suppl ; 127: 83-89, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31407068

RESUMO

There is considerable variability in the presentation of patients with acute subarachnoid hemorrhage (aSAH). Evidence suggests that a thick, diffuse clot better predicts the development of delayed cerebral ischemia and poor outcomes. In a rodent model of acute SAH, we directly measured the effects of the volume of blood injected versus the pattern of distribution of hemorrhage in the subarachnoid space on markers of early brain injury, namely, cerebral blood flow (CBF), cerebrospinal fluid (CSF) concentrations of P450 eicosanoids and catecholamines, and cortical spreading depolarizations (CSDs). There is a significant decrease in CBF, an increase in CSF biomarkers, and a trend toward increasing frequency and severity of CSDs when grouped by severity of hemorrhage but not by volume of blood injected. In severe hemorrhage grade animals, there was a progressive decrease in CBF after successive CSD events. These results suggest that the pattern of SAH (thick diffuse clots) correlates with the "clinical" severity of SAH.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Infarto Cerebral , Circulação Cerebrovascular , Hemorragia Subaracnóidea , Animais , Humanos , Ratos
16.
Br J Radiol ; 93(1105): 20190543, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31617743

RESUMO

OBJECTIVE: MR-perfusion post-processing still lacks standardization. This study evaluates the results of perfusion analysis with two established software solutions in a large series of patients with different diseases when a highly standardized processing workflow is ensured. METHODS: Multicenter data of 260 patients (80 with brain tumors, 124 with cerebrovascular disease and 56 with dementia examined with the same MR protocol) were analyzed. Raw data sets were processed with two software suites: Olea sphere and NordicICE. Group differences were analyzed with paired t-tests and one-way ANOVA. RESULTS: Perfusion metrics were significantly different for all examined diseases in the unaffected brain for both software suites [ratio cortex/white matter left hemisphere: mean transit time (MTT) 0.991 vs 0.847, p < 0.05; relative cerebral bloodflow (rBF) 3.23 vs 4.418, p < 0.001; relative cerebral bloodvolume (rBVc) 2.813 vs 3.884, p < 0.001; right hemisphere: MTT 1.079 vs 0.854, p < 0.05; rBF 3.262 vs 4.378, p < 0.001; rBVc 2.762 vs 3.935, p < 0.001)]. Perfusion results were also significantly different in patients with stroke (ratio cortex/white matter affected hemisphere: MTT 1.058 vs 0.784; p < 0.001), dementia (ratio cortex/white matter left hemisphere: rBVc 1.152 vs 1.795, p < 0.001; right hemisphere: rBVc 1.396 vs 1.662, p < 0.05) and brain tumors (ratio cortex/whole tumor rBVc: 0.778 vs 0.919, p < 0.001 and ratio cortex/tumor hotspot rBVc: 0.529 vs 0.512, p < 0.05). CONCLUSION: Despite a highly standardized workflow, parametric perfusion maps are depended on the chosen software. Radiologists should consider software related variances when using dynamic susceptibility contrast perfusion for clinical imaging and research. ADVANCES IN KNOWLEDGE: This multicenter study compared perfusion parameters calculated by two commercial dynamic susceptibility contrast perfusion post-processing software solutions in different central nervous system disorders with a large sample size and a highly standardized processing workflow. Despite, parametric perfusion maps are depended on the chosen software which impacts clinical imaging and research.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Transtornos Cerebrovasculares/diagnóstico por imagem , Demência/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Software , Circulação Cerebrovascular , Meios de Contraste , Feminino , Humanos , Masculino , Compostos Organometálicos , Perfusão
17.
J Assoc Physicians India ; 67(11): 71-73, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31793276

RESUMO

Cerebral Hyperperfusion syndrome is a relatively rare event following carotid revascularization. It can occur after both carotid endarterectomy and carotid artery stenting. It is characterized by focal neurodeficit, seizures and headache in the absence of ischemia. It occurs due to ipsilateral cerebral edema secondary to hyperperfusion. CT and MRI of the brain are the main modalities used for diagnosis and to rule out infarct. Prompt recognition and treatment can prevent permanent injury to the brain. We present a case of cerebral hyperperfusion syndrome in an elderly gentleman after a staged bilateral internal carotid artery stenting.


Assuntos
Isquemia Encefálica , Estenose das Carótidas , Circulação Cerebrovascular , Endarterectomia das Carótidas , Stents , Idoso , Isquemia Encefálica/etiologia , Artéria Carótida Interna , Estenose das Carótidas/cirurgia , Humanos , Stents/efeitos adversos , Síndrome
19.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde, LIS-bvsms | ID: lis-LISBR1.1-46871

RESUMO

A SBDCV é uma Sociedade Médica que reúne profissionais com interesse especial no estudo, pesquisa e assistência ao Acidente Vascular Cerebral (AVC). Atuamos de forma alinhada com o Departamento Científico de AVC da Academia Brasileira de Neurologia.


Assuntos
Acidente Vascular Cerebral , Circulação Cerebrovascular
20.
Zhonghua Nei Ke Za Zhi ; 58(11): 814-818, 2019 Nov 01.
Artigo em Chinês | MEDLINE | ID: mdl-31665856

RESUMO

Objective: To investigate the clinical significance of transcranial Doppler (TCD) in early diagnosis of sepsis-associated encephalopathy(SAE). Methods: Septic patients admitted to the intensive care unit(ICU) were recruited at Xiangya Hospital, Central South University from July 2015 to March 2016. Clinical data and TCD parameters during 24 hours after admission were collected. All patients were screened for delirium using the confusion assessment method for the intensive care unit (CAM-ICU) twice a day. The gold standard of the diagnosis of SAE was positive CAM-ICU evaluation. Patients were divided into SAE group and the non-SAE group. TCD data including systolic velocity (Vs), diastolic velocity (Vd), mean velocity (Vm), pulsatility index (PI) and resistant index (RI) were analyzed to determine the optimal diagnostic cut-off value. Results: A total of 43 patients were enrolled including 12 in SAE group and 31 in non-SAE group. Vm and Vd were lower in SAE group [Vm: (53.50±12.22) cm/s vs. (61.68±9.63) cm/s, P<0.05; Vd: (33.42±10.87) cm/s vs. (43.16±7.84) cm/s, P<0.01] but PI and RI were significant higher in SAE group[PI:(1.16±0.2) vs. (0.90±0.15), P<0.01;RI:(0.65±0.08) vs. (0.56±0.06), P<0.01] than in non-SAE group. The cut-off values of Vs, Vm, Vd, PI and RI for the diagnosis of SAE were 112cm/s, 55.50cm/s, 34.50cm/s, 1.16, 0.65, respectively, with the relevant sensitivities of 19.4%, 83.9%, 93.5%, 58.3%, 58.3% and the specificities of 100.0%, 50.0%, 58.3%, 96.8%, 96.8%, respectively. The diagnostic AUC of Vd, PI and RI were 0.741, 0.808 and 0.808 respectively. Conclusions: The parameter changes of TCD suggest that the pathogenesis of SAE is related to cerebral hypoperfusion, TCD is a helpful method for the early diagnosis of SAE.


Assuntos
Circulação Cerebrovascular , Artéria Cerebral Média/diagnóstico por imagem , Encefalopatia Associada a Sepse/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Diagnóstico Precoce , Humanos , Unidades de Terapia Intensiva
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