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1.
Eur J Neurol ; 28(1): 172-181, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32897605

RESUMO

BACKGROUND AND PURPOSE: Dysphagia is common in acute stroke and leads to worse overall outcome. Transesophageal echocardiography (TEE) is used in the diagnostic evaluation of stroke with regard to its etiology and is a known cause of postoperative dysphagia in cardiac surgery. The prevalence of dysphagia in acute stroke patients undergoing TEE remains unknown. The aim of the Transesophageal Echocardiography - Dysphagia Risk in Acute Stroke (TEDRAS) study was to assess the influence of TEE on swallowing among patients who have experienced acute stroke. METHODS: The TEDRAS study was a prospective, blind, randomized, controlled trial that included two groups of patients with acute stroke. Simple unrestricted randomization was performed, and examiners were blinded to each other's results. Swallowing was tested using flexible endoscopic evaluation of swallowing (FEES) at three different time points in the intervention group (24 h before, immediately after and 24 h after TEE) and in the control group (FEES on three consecutive days and TEE earliest after the third FEES). Validated scales were used to assess dysphagia severity for all time points as primary outcome measures. RESULTS: A total of 34 patients were randomized: 19 to the intervention group and 15 to the control group. The key findings of the repeated-measures between-group comparisons were significant increases in the intervention group for the following dysphagia measures: (1) secretion severity score (immediately after TEE: P < 0.001; 24 h after TEE: P < 0.001) and (2) Penetration-Aspiration Scale score for saliva (immediately after TEE: P < 0.001; 24 h after TEE: P = 0.007), for small (immediately after TEE: P = 0.009) and large liquid boli (immediately after TEE: P = 0.009; 24 h after TEE: P = 0.025). CONCLUSION: The results indicate a negative influence of TEE on swallowing in acute stroke patients for at least 24 hours.


Assuntos
Transtornos de Deglutição , Acidente Vascular Cerebral , Deglutição , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/etiologia , Ecocardiografia Transesofagiana , Humanos , Estudos Prospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem
2.
Eur J Neurosci ; 41(7): 965-75, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25615590

RESUMO

Factor VII activating protease (FSAP) is a circulating protease with a putative role in hemostasis, remodeling and inflammation. A polymorphism giving rise to low proteolytic activity has been associated with an increased risk of stroke and carotid stenosis. To date, no in vivo studies or mechanistic information is available to explain these results. Based on the polymorphism data we hypothesize that a lack of endogenous FSAP will increase the severity of stroke. Stroke was induced by applying thrombin in the middle cerebral artery in wild-type (WT) and FSAP(-/-) mice. Increased stroke volume and worsened neurological deficit were observed in FSAP(-/-) mice. Raised levels of FSAP protein were detected in the infarcted area of WT mice together with enhanced leukocyte infiltration and apoptosis in FSAP(-/-) mice. There was a concomitant increase in the activation of the NFκB pathway and decrease in expression of the PI3K/AKT pathway proteins. At a cellular level, FSAP increased cell survival and decreased apoptosis in primary cortical neurons and astrocytes exposed to tPA/NMDA excitotoxicity or oxygen glucose deprivation (OGD)/reoxygenation, respectively. This was mediated via the PI3K/AKT pathway with involvement of the protease activated receptor-1. To corroborate the human epidemiological data, which link FSAP with stroke, we now show that the lack of FSAP in mice worsens the outcome of stroke. In the absence of FSAP there was a stronger inflammatory response and lower cell survival due to insufficient activation of the PI3K/AKT pathway.


Assuntos
Isquemia Encefálica/enzimologia , Serina Endopeptidases/deficiência , Acidente Vascular Cerebral/enzimologia , Animais , Apoptose/fisiologia , Astrócitos/enzimologia , Astrócitos/patologia , Encéfalo/enzimologia , Encéfalo/patologia , Isquemia Encefálica/patologia , Movimento Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média , Leucócitos/patologia , Leucócitos/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/enzimologia , Neurônios/patologia , Receptor PAR-1/metabolismo , Serina Endopeptidases/genética , Vazamento Acidental em Seveso , Acidente Vascular Cerebral/patologia , Trombina
3.
Naunyn Schmiedebergs Arch Pharmacol ; 396(12): 3887-3892, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37261475

RESUMO

Cerebral sinus venous thrombosis (CSVT) is an uncommon disease that is usually treated with anticoagulation (heparin, low-molecular heparin, or vitamin K-antagonists). We compared treatment with edoxaban, an oral factor Xa-antagonist, that has not been approved in patients with CSVT, with enoxaparin, a well-established therapy, in a rat model of CSVT. Fifty male Wistar rats were randomized into 5 groups (10 animals each) and subjected to aluminum chloride (AlCl3)-induced thrombosis of the superior sagittal sinus (SSS) or sham procedure. Animals with thrombosis of the SSS were treated with edoxaban, enoxaparin, or placebo. Diagnostic workup included neurological examination, MRI imaging, MR-flow measurements of the SSS, and immunohistochemical staining. Neurological examination revealed no differences between treatment groups. Seven days after initial thrombosis, flow in the SSS was lower in the active treatment group as compared to sham-operated animals (p < 0.05). Flow in the SSS in the active treatment groups (edoxaban 1 h prior to thrombosis: 0.16 cm/s ± 0.06 cm/s; edoxaban 6 h after thrombosis: 0.13 cm/s ± 0.05 cm/s; enoxaparin: 0.13 cm/s ± 0.04 cm/s; placebo: 0.07 cm/s ± 0.02 cm/s) was higher as compared to placebo (p < 0.05), but there were no differences between the active treatment groups (p > 0.05). Immunohistochemical staining showed no differences in the actively treated animals. Edoxaban proved to be similar to enoxaparin in a model of experimental AlCl3-induced CSVT.


Assuntos
Enoxaparina , Trombose , Humanos , Masculino , Ratos , Animais , Enoxaparina/farmacologia , Enoxaparina/uso terapêutico , Seio Sagital Superior , Ratos Wistar , Inibidores do Fator Xa/farmacologia , Inibidores do Fator Xa/uso terapêutico , Heparina/farmacologia , Trombose/induzido quimicamente , Trombose/tratamento farmacológico
4.
Nervenarzt ; 82(2): 190, 192-7, 2011 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-21347853

RESUMO

Over 100,000 heart surgeries are performed in Germany annually. Although severe neurological complications like ischaemic strokes have meanwhile become rare occurrences, subtle neuropsychological changes are still frequently recognized after major heart surgeries. The hitherto unsolved problem of postoperative cognitive decline (POCD) is portrayed in this article. Multifactorial aetiologies including microembolism and preoperative risk factors are supposed to play a significant role in POCD. A variety of neuroprotective strategies such as intraoperative microemboli filtration have been suggested to minimize cerebral risks. The utility of neuroprotective methods has recently been verified in randomized studies.


Assuntos
Isquemia Encefálica/epidemiologia , Isquemia Encefálica/prevenção & controle , Procedimentos Cirúrgicos Cardiovasculares/estatística & dados numéricos , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Comorbidade , Alemanha/epidemiologia , Humanos , Fármacos Neuroprotetores/uso terapêutico , Prevalência , Medição de Risco , Fatores de Risco
5.
J Neuroimmunol ; 197(1): 81-6, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18479754

RESUMO

Paraneoplastic neurological syndromes (PNS) are often associated with antineuronal autoantibodies and many of them could be identified in the recent years. However, there are still new antineuronal binding patterns with yet unidentified autoantigens. We here describe a new autoantibody associated with paraneoplastic sensorimotor and autonomic neuropathy in a patient with small cell lung cancer. In indirect immunofluorescence test, the patient's serum colocalised with the synaptic protein synaptophysin in the cerebellum and myenteric plexus of the gut. Immunoblotting showed a 38 kDa reactivity, which is also the molecular weight of synaptophysin. Therefore a Western Blot with recombinant synaptophysin has been used and revealed reactivity of the serum against synaptophysin. In patients with non-paraneoplastic neuropathies or healthy controls, anti-synaptophysin autoantibodies were not detectable. In 20 SCLC patients without neurological syndromes, two patients had low-titer anti-synaptophysin autoantibodies. The patient's serum and IgG fraction showed cytotoxicity to primary cultured myenteric plexus neurons. We conclude that synaptophysin is an autoantigen in paraneoplastic neurological syndromes.


Assuntos
Autoantígenos/imunologia , Polineuropatia Paraneoplásica/imunologia , Sinaptofisina/imunologia , Animais , Citotoxicidade Celular Dependente de Anticorpos , Autoanticorpos/metabolismo , Autoanticorpos/toxicidade , Autoantígenos/metabolismo , Western Blotting , Morte Celular/imunologia , Linhagem Celular Tumoral , Testes Imunológicos de Citotoxicidade , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/toxicidade , Masculino , Pessoa de Meia-Idade , Plexo Mientérico/citologia , Plexo Mientérico/imunologia , Neurônios/citologia , Neurônios/imunologia , Polineuropatia Paraneoplásica/diagnóstico , Ratos , Ratos Wistar , Sinaptofisina/metabolismo
6.
Eur J Neurol ; 15(12): 1390-4, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19049559

RESUMO

BACKGROUND: Paraneoplastic neurological syndromes (PNS) are mainly associated with small-cell lung cancer, gynaecological tumours and lymphomas. Few studies report the association of neurological syndromes with a carcinoid, the majority being a serotonin-related myopathy. We report four patients with a PNS associated with carcinoid. PATIENTS AND RESULTS: The clinical syndromes were sensory neuropathy, limbic encephalitis, myelopathy and brain stem encephalitis. Two patients had antineuronal autoantibodies (one anti-Hu, one anti-Yo), one patient had antinuclear antibodies, and one patient had no autoantibodies. For two of the carcinoids, expression of HuD in the tumour could be demonstrated. CONCLUSION: This study demonstrates that carcinoids can also be associated with classical antineuronal antibody-associated PNS.


Assuntos
Tumor Carcinoide/complicações , Síndromes Paraneoplásicas/etiologia , Idoso , Autoanticorpos/imunologia , Biomarcadores/análise , Biomarcadores/metabolismo , Tumor Carcinoide/patologia , Tumor Carcinoide/fisiopatologia , Proteínas ELAV/imunologia , Encefalite/etiologia , Encefalite/patologia , Encefalite/fisiopatologia , Feminino , Humanos , Encefalite Límbica/patologia , Encefalite Límbica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/imunologia , Polineuropatia Paraneoplásica/patologia , Polineuropatia Paraneoplásica/fisiopatologia , Síndromes Paraneoplásicas/patologia , Síndromes Paraneoplásicas/fisiopatologia , Doenças da Medula Espinal/etiologia , Doenças da Medula Espinal/patologia , Doenças da Medula Espinal/fisiopatologia , Adulto Jovem
7.
Ann N Y Acad Sci ; 1107: 104-10, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17804537

RESUMO

Paraneoplastic neurological syndromes are clinically heterogeneous manifestations of cancer, but are not caused by the tumor or its metastases. Because autoantibodies reacting with tumor and nervous system tissue have been described, an autoimmune pathogenesis is suspected. Most autoantibodies are directed against neuronal proteins. Here, we describe the impact of antiglial autoantibodies in paraneoplastic neurological syndromes. Anti-CRMP5 and antiglial nuclear antibody both can be associated with different paraneoplastic neurological syndromes and tumors.


Assuntos
Antígenos/imunologia , Autoanticorpos/imunologia , Neuroglia/imunologia , Síndromes Paraneoplásicas do Sistema Nervoso/imunologia , Animais , Autoimunidade/imunologia , Núcleo Celular/imunologia , Humanos , Síndromes Paraneoplásicas do Sistema Nervoso/patologia
8.
Eur J Neurol ; 14(2): 199-205, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17250730

RESUMO

Myeloproliferative disorders (MPD) are associated with an increased risk for thrombembolic events. In this study, we examined the prognostic value of transcranial Doppler (TCD) microemboli detection regarding clinical events and correlated TCD findings with results of blood cell counts and platelet flow cytometry to gain insight into the composition of circulating microemboli in these patients. In a cohort of 42 patients with MPD TCD microemboli detection was performed on a single occasion and correlated with thrombembolic events during a prospective follow up of 29.7 +/- 7.3 month. In all patients, a complete blood count and in 17 patients platelet flow cytometry were performed on the day of the TCD examination. Microembolic signals (MES) were recorded in 15 (35.7%) patients, however, without any correlation with the type of MPD, blood cell counts, or thrombembolic events [9 (21.4%)]. MES positive and negative patients did not differ regarding the levels of activated platelets, platelet microaggregates, or microparticles. We found a strong trend for higher rates of platelet-neutrophil conjugates in MES positive patients (P = 0.09). Detection of MES by TCD on a single occasion in MPD patients has only limited prognostic value. MES do not correlate with the type of MPD, nor blood cell counts. Flow cytometry suggests that MES in MPD may consist of platelet-neutrophil aggregates.


Assuntos
Embolia Intracraniana/diagnóstico por imagem , Embolia Intracraniana/etiologia , Transtornos Mieloproliferativos/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Contagem de Células Sanguíneas , Plaquetas/patologia , Agregação Celular , Estudos de Coortes , Estudos Transversais , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Embolia Intracraniana/sangue , Embolia Intracraniana/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Prognóstico , Tromboembolia/etiologia , Ultrassonografia Doppler Transcraniana
9.
Gen Physiol Biophys ; 25(2): 207-14, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16917133

RESUMO

Serious postoperative psycho-neurological dysfunction is at least partially attributed to the occurrence of gaseous microbubbles in the arterial line of extracorporeal circulation (ECC). Therefore, we investigated in a prospective randomized double blind study whether the usage of dynamic bubble trap (DBT) will reduce microbubble load of patients undergoing aortic valve replacement. Patients (n = 41) were divided into group I (GI, n = 22) with DBT introduced into the arterial line of ECC and group II (GII, n = 19) with placebo-DBT instead. Doppler ultrasonography was used for detection of microbubbles before and after DBT, and for detection of high intensity transient signals (HITS) within the middle cerebral artery. The recording time during ECC was divided into period 1 (P1, until aortic clamp removal) and period 2 (P2, clamp removal until the end of ECC). A significant reduction of microbubble load was found in GI only (p < 0.0001 for ECC; p < 0.0001 for P1; p < 0.0025 for P2). A significant difference in number of HITS between the groups was observed in P1 only (p < 0.002 left middle cerebral artery, p < 0.005 right middle cerebral artery), since in P2 the trapped air in left chamber can go to the supraaortal vessels without passing ECC. In conclusion the use of DBT cannot substitute careful venting after aortic declamping. Nevertheless, reduction of HITS in the cross-clamped period of ECC justifies the use of DBT in patients undergoing open chamber surgery.


Assuntos
Valva Aórtica/patologia , Próteses Valvulares Cardíacas , Microbolhas , Aorta/patologia , Método Duplo-Cego , Embolia Aérea , Circulação Extracorpórea , Feminino , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Masculino , Modelos Estatísticos , Estudos Prospectivos , Ultrassonografia Doppler Transcraniana/métodos
10.
Lab Anim ; 40(1): 1-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16460584

RESUMO

Investigating focal cerebral ischaemia requires animal models that are relevant to human stroke. This study was designed to evaluate the influence of early reperfusion and choice of rat strains on infarct volume and oedema formation. Thirty-six Wistar and Sprague-Dawley rats were subjected to temporary middle cerebral artery occlusion (MCAO) for 90 min (groups I and II) or to permanent MCAO (groups III and IV) using the suture technique. Ischaemic lesion volume and oedema formation were quantified 24 h after MCAO using 7T-magnetic resonance imaging (MRI). Impact of rat strains: Reperfusion led to significant larger ischaemic lesion volumes in Wistar rats as compared to Sprague-Dawley rats (P<0.0005). Oedema formation was similar in both rat strains. Permanent MCAO led to significantly larger ischaemic lesion volumes in Sprague-Dawley rats (P<0.05). Oedema formation, however, was significantly more accentuated in Wistar rats (P<0.005). Impact of reperfusion: Reperfusion did not cause any changes in ischaemic lesion volume in Wistar rats. Oedema formation, however, was significantly reduced (P<0.0005). In Sprague-Dawley rats, reperfusion caused a significant reduction of ischaemic lesion volume (P<0.00005), but did not modify oedema formation. These findings emphasize the critical importance of rat strain differences in experimental stroke research.


Assuntos
Edema Encefálico/patologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/patologia , Ataque Isquêmico Transitório/patologia , Animais , Edema Encefálico/etiologia , Edema Encefálico/fisiopatologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/fisiopatologia , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/fisiopatologia , Imageamento por Ressonância Magnética , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Especificidade da Espécie
11.
Rofo ; 177(11): 1513-21, 2005 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-16302132

RESUMO

PURPOSE: To retrospectively assess the indication for thoracic real-time MRI, demonstrate typical findings, analyze the diagnostic potential in subgroups with suspected pulmonary embolism (PE) and aortic dissection (AD), and describe the influence of real-time MRI on the role of MRI in acute thoracic diseases. MATERIALS AND METHODS: From July 2001 to February 2005, real-time MRI was applied in 2,256 examinations in 1,714 patients. MRI was the primary diagnostic modality for these thoracic diseases as computed tomography has been available only since 2003. Characteristics of the TrueFISP sequence applied were: TR/TE/flip angle 3.1 ms/1.6 ms/59 degrees , respectively. FOV 340 - 360 mm, matrix size 156 to 192 x 256 pixels, slice thickness 3 to 4 mm, slices overlapped by 50 %. Acquisition time was 0.4 to 0.5 s per image. Three hundred and twenty transverse, coronal and sagittal images were acquired in three minutes. No breath holding, and only minimal patient cooperation, was required. Turbo-spin-echo sequences as well as ECG-gated and contrast-enhanced sequences were added depending on the indication. RESULTS: Most common indications were: acute thoracic nonspecified disease (n = 276, 12.24 %), PE (n = 573, 25.4 %), bleeding (n = 154, 6.8 %), AD (n = 222, 9.8 %), topographic information in complex findings (n = 654, 29.0 %). Real-time MRI was the sole MRI technique applied in 180 examinations (8.0 %), ECG-gated real-time MRI was applied in 87 examinations and breath hold was used in 107 examinations. PE was diagnosed in 181 examinations; reference techniques (MRI, computed tomography, single photon emission computed tomography) confirmed 170 of these and detected 19 more cases (sensitivity 90.0 %, specificity 97.1 %). Real-time MRI detected 141 suspected AD and 53 more nonsuspected AD. Of these, 191 were confirmed by other MRI techniques, surgery or clinical course (98.5 %). Real-time MRI coincidentally detected 56 pulmonary tumors, all were confirmed with computed tomography. Thus, especially vascular diseases could be easily assessed with real-time MRI, while computed tomography had advantages in the evaluation of the lung parenchyma. CONCLUSION: Real-time MRI both enables emergency MRI examinations for thoracic diseases in clinical patients in unstable condition and allows an explorative style of working in patients with nondefined acute thoracic diseases.


Assuntos
Aneurisma da Aorta Torácica/diagnóstico , Dissecção Aórtica/diagnóstico , Imageamento por Ressonância Magnética/métodos , Embolia Pulmonar/diagnóstico , Doenças Torácicas/diagnóstico , Doença Aguda , Adulto , Idoso , Dissecção Aórtica/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Artefatos , Diagnóstico Diferencial , Imagem Ecoplanar , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Embolia Pulmonar/diagnóstico por imagem , Radiografia Torácica , Estudos Retrospectivos , Doenças Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
12.
Stroke ; 32(2): 442-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11157180

RESUMO

BACKGROUND AND PURPOSE: Transcranial color-coded duplex sonography (TCCS) allows bedside imaging of intracranial hemodynamics and parenchymal structures. It provides reliable information regarding midline shift (MLS) in space-occupying hemispheric stroke. We studied the value of MLS measurement to predict fatal outcome at different time points after stroke onset. METHODS: Forty-two patients with acute, severe hemispheric stroke were enrolled. Cranial computed tomography (CCT) and extracranial duplex sonography were performed on admission. TCCS was carried out 8+/-3, 16+/-3, 24+/-3, 32+/-3, and 40+/-3 hours after stroke onset. Lesion size was determined from follow-up CCT. RESULTS: Twelve patients died as the result of cerebral herniation (group 1); 28 survived (group 2). Two patients received decompressive hemicraniectomy and were therefore excluded from further evaluation. MLS was significantly higher in group 1 as early as 16 hours after onset of stroke. Specificity and positive predictive values for death caused by cerebral herniation of MLS >/=2.5, 3.5, 4.0, and 5.0 mm after 16, 24, 32, and 40 hours were 1.0. CONCLUSIONS: TCCS helps to estimate outcome as early as 16 hours after stroke onset and thus facilitates identification of patients who are unlikely to survive without decompressive craniectomy. Because of its noninvasive character and bedside suitability, sonographic monitoring of MLS might be a useful tool in management of critically ill patients who cannot undergo repeated CCT scans.


Assuntos
Acidente Vascular Cerebral/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Idoso , Edema Encefálico/etiologia , Edema Encefálico/mortalidade , Edema Encefálico/prevenção & controle , Descompressão Cirúrgica , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/cirurgia , Taxa de Sobrevida , Terceiro Ventrículo/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada por Raios X
13.
Stroke ; 34(9): 2234-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12920258

RESUMO

BACKGROUND AND PURPOSE: Permanent middle cerebral artery occlusion (MCAO) with the use of the suture technique causes hypothalamic damage with subsequent hyperthermia, which can confound neuroprotective drug studies. In the present study the neuroprotective effects of dizocilpine (MK-801) were compared in different permanent MCAO models with and without hypothalamic damage and hyperthermia. METHODS: Sixty Sprague-Dawley rats were treated with MK-801 or placebo, beginning 15 minutes before MCAO, and assigned to the following groups: suture MCAO (group I), macrosphere MCAO without hypothalamic damage (group II), or macrosphere MCAO with intentionally induced hypothalamic infarction (group III). Body temperature was measured at 3, 6, and 24 hours. Lesion size was determined after 24 hours (2,3,5-triphenyltetrazolium chloride staining). RESULTS: Hypothalamic damage was present in animals in group I and was intentionally induced in group III with the use of a modified macrosphere MCAO technique. Body temperature was significantly increased 3, 6, and 24 hours after MCAO in these 2 groups of animals. Hypothalamic damage and subsequent hyperthermia could be avoided effectively by limiting the number of macrospheres (group II). MK-801 provided a highly significant neuroprotective effect in group II but not in groups I and III. CONCLUSIONS: Hypothalamic damage with subsequent hyperthermia masked the neuroprotective effect of MK-801. This side effect can be avoided by using the macrosphere MCAO technique with a limited number of spheres. This model therefore may be more appropriate to study the effects of neuroprotective drugs in permanent focal cerebral ischemia than the suture method.


Assuntos
Maleato de Dizocilpina/uso terapêutico , Hipotálamo/fisiopatologia , Fármacos Neuroprotetores/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/fisiopatologia , Animais , Temperatura Corporal , Modelos Animais de Doenças , Progressão da Doença , Febre/etiologia , Febre/patologia , Febre/prevenção & controle , Hipotálamo/patologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/fisiopatologia , Ligadura , Masculino , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/complicações , Titânio , Resultado do Tratamento
14.
Stroke ; 35(2): 566-71, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14739415

RESUMO

BACKGROUND AND PURPOSE: Brain edema is a life-threatening consequence of stroke and leads to an extension of the affected tissue. The space-occupying effect due to brain edema can be quantified in rat stroke models with the use of MRI. The present study was performed to test 2 hypotheses: (1) Can quantification of the space-occupying effect due to brain edema serve as a noninvasive measure for brain water content? (2) Does morphometric assessment of brain swelling allow determination of true infarct size on MRI after correction for the space-occupying effect of edema? METHODS: Thirty rats were subjected to permanent suture middle cerebral artery occlusion. MRI was performed after 6 or 24 hours, and hemispheric swelling was assessed morphometrically. Interobserver and intraobserver agreements were determined for MRI measurements. In study I, the space-occupying effect due to brain edema was correlated with the absolute brain water content by the wet/dry method. In study II, lesion volumes corrected and uncorrected for edema were calculated on MRI and on TTC staining and compared. RESULTS: Interobserver and intraobserver agreements for MRI measurements were excellent (r>or=0.97). Brain water content and hemispheric swelling correlated well after 6 and 24 hours (r>or=0.95). Corrected lesion volumes correlated with r=0.78 between TTC staining and MRI. Without edema correction, lesion volumes were overestimated by 20.3% after 6 hours and by 29.6% after 24 hours of ischemia. CONCLUSIONS: Morphometric assessment of hemispheric swelling on MRI can determine the increase in absolute brain water content noninvasively and can also provide ischemic lesion volumes corrected for brain edema.


Assuntos
Edema Encefálico/patologia , Encéfalo/metabolismo , Acidente Vascular Cerebral/patologia , Água/metabolismo , Animais , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Edema Encefálico/etiologia , Edema Encefálico/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Imageamento por Ressonância Magnética , Masculino , Variações Dependentes do Observador , Projetos Piloto , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/complicações , Água/análise
15.
Stroke ; 31(10): 2342-5, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11022061

RESUMO

BACKGROUND AND PURPOSE: A number of controlled trials have evaluated the benefit of intravenous thrombolysis in acute stroke with inconsistent results. None of these studies assessed the initial vascular status or provided information regarding the recanalization rate after therapy. Further trials need to clarify whether certain subgroups might possibly benefit more than others from intravenous thrombolysis. Therefore, a fast and valid method for assessment of cerebrovascular status is needed. In this multicenter study, we evaluated the potentials and limitations of color-coded duplex sonography (TCCS) for cerebrovascular status assessment in acute stroke patients before and after therapy. Furthermore, we compared the recanalization rate for patients referred to thrombolytic and conservative medical therapy. METHODS: Fifty-eight patients suffering from hemispheric stroke were enrolled consecutively in 8 centers. Duplex sonography was performed on admission, 2 hours after start of therapy, and 24 hours after onset of symptoms. Therapy was started within 6 hours. RESULTS: Intravenous thrombolysis was performed in 18 patients, conservative medical therapy in 39 patients, and early thromboendarterectomy in 1 patient. The middle cerebral artery (MCA) mainstem was patent in 29 patients (53.7%), occluded in 25 (46.3%), and was not assessable in 4 patients. Recanalization of the occluded MCA after 2 and 24 hours was diagnosed in 50% and 78% of the patients treated with rtPA and in 0% and 8% in the conservatively treated patients. CONCLUSIONS: Intravenous thrombolysis is highly effective in restoring blood flow after MCA occlusion. TCCS is suitable for assessment of the cerebrovascular status in acute stroke and therefore might define therapeutically relevant subgroups of patients in future stroke trials on the basis of their vascular pathology.


Assuntos
Circulação Cerebrovascular , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Artérias Carótidas/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Endarterectomia , Feminino , Humanos , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento , Ultrassonografia Doppler em Cores/métodos , Grau de Desobstrução Vascular/efeitos dos fármacos
16.
Neurology ; 52(6): 1133-7, 1999 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-10214733

RESUMO

OBJECTIVE: To evaluate the diagnostic efficiency and accuracy of contrast-enhanced transcranial color-coded sonography (CE-TCCS). BACKGROUND: TCCS is hampered by insufficient ultrasonic penetration in 20% of cerebrovascular patients. METHODS: In 47 patients whose basal arteries could not be assessed adequately, 59 TCCS examinations were performed before and after administration of the ultrasonic contrast agent (CA) Levovist. The assessability of different basal cerebral arteries after CA administration was evaluated off-line. Angiographic records were available from 11 patients. RESULTS: Satisfactory investigation of the middle cerebral artery, the anterior cerebral artery, the P1 and P2 segments of the posterior cerebral artery, and the supraclinoid portion of the internal carotid artery siphon was possible in 5.1%, 28.8%, 35.6%, 55.9%, and 47.5% of patients before, and in 84.7%, 91.5%, 93.2%, 94.5%, and 93.2% of patients after contrast enhancement. Stenoses or occlusions of basal cerebral arteries were registered in 28 patients (60%). CE-TCCS diagnosis was confirmed by digital subtraction angiography or magnetic resonance angiography in 10 of the 11 patients, leading to positive and negative predictive values of 0.86 and 1.00. CONCLUSION: Contrast enhancement improves the diagnostic potential of TCCS significantly in patients with temporal bone window failure, and proved to be a reliable method for detecting middle cerebral artery and siphon occlusion.


Assuntos
Transtornos Cerebrovasculares/diagnóstico por imagem , Ultrassonografia Doppler em Cores/métodos , Ultrassonografia Doppler Transcraniana/métodos , Adulto , Idoso , Artérias Cerebrais/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
17.
Neurology ; 52(1): 45-9, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-9921847

RESUMO

BACKGROUND AND OBJECTIVE: Transcranial color-coded sonography (TS) allows a noninvasive, accurate evaluation of lateral displacement of the third ventricle. The authors studied the prognostic value of TS monitoring of the midline shift (MLS) in acute hemispheric stroke. METHOD: Sixteen patients with acute middle cerebral artery (MCA) occlusion were investigated. On admission, the median modified Scandinavian Stroke Scale (mSSS) score was 6.0 (range, 5 to 8). Five patients died from cerebral herniation (group 1), 10 survived (group 2), and 1 patient (Patient 16) survived after decompressive surgery. TS was performed on days 1 to 4 (10 +/- 3, 32 +/- 4, 57 +/- 5, and 82 +/- 5 hours after onset of symptoms). Distance from the TS probe to the center of the third ventricle was measured both from the symptomatic (A) and asymptomatic (B) sides. MLS was calculated using the formula MLS = (A - B)/2. RESULTS: Ten hours after stroke onset, MLS and mSSS scores were not significantly different between the two groups. At 32, 57, and 82 hours, MLS was higher in group 1 (32 hours, p = 0.001; 57 hours, p = 0.003; 82 hours, p = 0.023) whereas there was no difference in mSSS score after 32 hours. All patients with an MLS < 4 mm at 32 hours survived, whereas patients with an MLS > 4 mm died as a result of cerebral herniation, with the exception of the one patient who underwent decompressive hemicraniectomy. CONCLUSIONS: The study of MLS at 32 hours after stroke onset in patients with severe MCA infarctions may identify patients who are unlikely to survive. The value of MLS in determining the indication of decompressive craniectomy merits further study.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Infarto Cerebral/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias Cerebrais/fisiologia , Infarto Cerebral/complicações , Infarto Cerebral/cirurgia , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/patologia , Circulação Cerebrovascular/fisiologia , Craniotomia , Descompressão Cirúrgica , Progressão da Doença , Feminino , Hérnia/diagnóstico por imagem , Hérnia/etiologia , Herniorrafia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Tomografia Computadorizada por Raios X
18.
Neurology ; 55(11): 1741-3, 2000 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-11113236

RESUMO

Neurologic injury subsequent to decompression from diving may be due to paradoxical arterialization of venous gas emboli. Of 40 divers who performed 53 open water dives after being tested for a patent foramen ovale (PFO), arterial gas emboli were detected in 7 of 13 dives, which resulted in venous bubbles. In five of these seven dives, there was evidence of a PFO by contrast transcranial Doppler sonography, indicating an increased risk of arterializing venous bubbles in divers with a PFO.


Assuntos
Doença da Descompressão , Mergulho , Embolia Aérea/fisiopatologia , Adulto , Temperatura Baixa/efeitos adversos , Embolia Aérea/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia Doppler
19.
AJNR Am J Neuroradiol ; 20(8): 1567-71, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10512247

RESUMO

BACKGROUND AND PURPOSE: Transcranial color-coded duplex sonography (TCCS) allows the noninvasive, easily reproducible measurement of midline dislocation (MLD) of the third ventricle in space-occupying stroke, even in critically ill patients. However, the method has been validated only in a small number of subjects. The aim of this study was to test the method under clinical conditions. METHODS: In 61 prospectively recruited patients (mean age, 62+/-15 years) with supratentorial ischemic infarction or intracranial hemorrhage, the sonographic measurement of MLD was compared with cranial CT data in a 12-hour time window. Subgroup analysis was also undertaken for comparing TCCS and cranial CT measurements within a 3-hour time window. RESULTS: One hundred twenty-two data pairs of TCCS and cranial CT MLD measurements were correlated within the 12-hour time window. TCCS and cranial CT measurements of MLD correlated both in the total patient group and in the different subgroups with coefficients of over 0.9. The 2-SD confidence interval of the difference between the TCCS measurements and the respective means of both methods in the total patient collective was +/-1.78 mm. CONCLUSION: TCCS provides a noninvasive, easily reproducible and reliable method for monitoring MLD of the third ventricle in stroke patients. It is particularly suitable for critically ill patients who are not fit for transportation.


Assuntos
Infarto da Artéria Cerebral Média/diagnóstico , Hemorragias Intracranianas/diagnóstico , Terceiro Ventrículo/patologia , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana , Adulto , Idoso , Idoso de 80 Anos ou mais , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
20.
J Neuroimaging ; 5(2): 105-8, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7718936

RESUMO

Transcranial duplex color-flow sonography provides visualization of intracranial structures, and measures angle-corrected blood flow velocity in the basal cerebral arteries of adults. In 44 patients with central nervous system disease, the oblique diameters of the third and the middle part of the lateral ventricle were measured by transcranial duplex color-flow sonography using a system with a 2.5-MHz transducer, and compared to computed tomography measurements. The correlation coefficients for the third and lateral ventricle measurements were r = 0.83 (p < 0.0001, N = 38) and 0.73 (p < 0.0001, N = 78), respectively. A second investigation was performed by transcranial duplex to evaluate intraobserver and interobserver reproducibility. The correlation coefficient representing interobserver reproducibility in 27 patients was r = 0.87 (p < 0.0001, N = 47) for the lateral ventricle and r = 0.9 (p < 0.0001, N = 49) for the third ventricle. The intraobserver reproducibility correlation coefficient was r = 0.93 (p < 0.0001, N = 22) for the lateral ventricle in 12 patients. In 49 healthy volunteers the oblique diameters of the lateral and third ventricles were age dependent, measuring 16.7 +/- 2.3 mm and 4.8 +/- 1.9 mm, respectively, in those younger than 59 years, compared to 19.0 +/- 2.9 mm and 7.6 +/- 2.1 mm in those 60 years or older. Therefore, transcranial duplex color-flow sonography measures noninvasively the third and the lateral ventricle in adults.


Assuntos
Ventrículos Cerebrais/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Doenças do Sistema Nervoso Central/diagnóstico por imagem , Doenças do Sistema Nervoso Central/fisiopatologia , Ventriculografia Cerebral , Estudos de Coortes , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
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