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1.
Eur J Neurol ; 28(1): 172-181, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32897605

RESUMEN

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.


Asunto(s)
Trastornos de Deglución , Accidente Cerebrovascular , Deglución , Trastornos de Deglución/diagnóstico por imagen , Trastornos de Deglución/epidemiología , Trastornos de Deglución/etiología , Ecocardiografía Transesofágica , Humanos , Estudios Prospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen
2.
Eur J Neurosci ; 41(7): 965-75, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25615590

RESUMEN

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.


Asunto(s)
Isquemia Encefálica/enzimología , Serina Endopeptidasas/deficiencia , Accidente Cerebrovascular/enzimología , Animales , Apoptosis/fisiología , Astrocitos/enzimología , Astrocitos/patología , Encéfalo/enzimología , Encéfalo/patología , Isquemia Encefálica/patología , Movimiento Celular/fisiología , Supervivencia Celular/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media , Leucocitos/patología , Leucocitos/fisiología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Neuronas/enzimología , Neuronas/patología , Receptor PAR-1/metabolismo , Serina Endopeptidasas/genética , Liberación Accidental en Seveso , Accidente Cerebrovascular/patología , Trombina
3.
Naunyn Schmiedebergs Arch Pharmacol ; 396(12): 3887-3892, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37261475

RESUMEN

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.


Asunto(s)
Enoxaparina , Trombosis , Humanos , Masculino , Ratas , Animales , Enoxaparina/farmacología , Enoxaparina/uso terapéutico , Seno Sagital Superior , Ratas Wistar , Inhibidores del Factor Xa/farmacología , Inhibidores del Factor Xa/uso terapéutico , Heparina/farmacología , Trombosis/inducido químicamente , Trombosis/tratamiento farmacológico
4.
Nervenarzt ; 82(2): 190, 192-7, 2011 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-21347853

RESUMEN

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.


Asunto(s)
Isquemia Encefálica/epidemiología , Isquemia Encefálica/prevención & control , Procedimientos Quirúrgicos Cardiovasculares/estadística & datos numéricos , Trastornos del Conocimiento/epidemiología , Trastornos del Conocimiento/prevención & control , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Comorbilidad , Alemania/epidemiología , Humanos , Fármacos Neuroprotectores/uso terapéutico , Prevalencia , Medición de Riesgo , Factores de Riesgo
5.
J Neuroimmunol ; 197(1): 81-6, 2008 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-18479754

RESUMEN

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.


Asunto(s)
Autoantígenos/inmunología , Polineuropatía Paraneoplásica/inmunología , Sinaptofisina/inmunología , Animales , Citotoxicidad Celular Dependiente de Anticuerpos , Autoanticuerpos/metabolismo , Autoanticuerpos/toxicidad , Autoantígenos/metabolismo , Western Blotting , Muerte Celular/inmunología , Línea Celular Tumoral , Pruebas Inmunológicas de Citotoxicidad , Técnica del Anticuerpo Fluorescente Indirecta , Humanos , Inmunoglobulina G/toxicidad , Masculino , Persona de Mediana Edad , Plexo Mientérico/citología , Plexo Mientérico/inmunología , Neuronas/citología , Neuronas/inmunología , Polineuropatía Paraneoplásica/diagnóstico , Ratas , Ratas Wistar , Sinaptofisina/metabolismo
6.
Eur J Neurol ; 15(12): 1390-4, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19049559

RESUMEN

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.


Asunto(s)
Tumor Carcinoide/complicaciones , Síndromes Paraneoplásicos/etiología , Anciano , Autoanticuerpos/inmunología , Biomarcadores/análisis , Biomarcadores/metabolismo , Tumor Carcinoide/patología , Tumor Carcinoide/fisiopatología , Proteínas ELAV/inmunología , Encefalitis/etiología , Encefalitis/patología , Encefalitis/fisiopatología , Femenino , Humanos , Encefalitis Límbica/patología , Encefalitis Límbica/fisiopatología , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/inmunología , Polineuropatía Paraneoplásica/patología , Polineuropatía Paraneoplásica/fisiopatología , Síndromes Paraneoplásicos/patología , Síndromes Paraneoplásicos/fisiopatología , Enfermedades de la Médula Espinal/etiología , Enfermedades de la Médula Espinal/patología , Enfermedades de la Médula Espinal/fisiopatología , Adulto Joven
7.
Ann N Y Acad Sci ; 1107: 104-10, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17804537

RESUMEN

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.


Asunto(s)
Antígenos/inmunología , Autoanticuerpos/inmunología , Neuroglía/inmunología , Síndromes Paraneoplásicos del Sistema Nervioso/inmunología , Animales , Autoinmunidad/inmunología , Núcleo Celular/inmunología , Humanos , Síndromes Paraneoplásicos del Sistema Nervioso/patología
8.
Eur J Neurol ; 14(2): 199-205, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17250730

RESUMEN

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.


Asunto(s)
Embolia Intracraneal/diagnóstico por imagen , Embolia Intracraneal/etiología , Trastornos Mieloproliferativos/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Recuento de Células Sanguíneas , Plaquetas/patología , Agregación Celular , Estudios de Cohortes , Estudios Transversales , Femenino , Citometría de Flujo , Estudios de Seguimiento , Humanos , Embolia Intracraneal/sangre , Embolia Intracraneal/patología , Masculino , Persona de Mediana Edad , Neutrófilos/patología , Pronóstico , Tromboembolia/etiología , Ultrasonografía Doppler Transcraneal
9.
Gen Physiol Biophys ; 25(2): 207-14, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16917133

RESUMEN

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.


Asunto(s)
Válvula Aórtica/patología , Prótesis Valvulares Cardíacas , Microburbujas , Aorta/patología , Método Doble Ciego , Embolia Aérea , Circulación Extracorporea , Femenino , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Masculino , Modelos Estadísticos , Estudios Prospectivos , Ultrasonografía Doppler Transcraneal/métodos
10.
Lab Anim ; 40(1): 1-8, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16460584

RESUMEN

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.


Asunto(s)
Edema Encefálico/patología , Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media/patología , Ataque Isquémico Transitorio/patología , Animales , Edema Encefálico/etiología , Edema Encefálico/fisiopatología , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/fisiopatología , Ataque Isquémico Transitorio/complicaciones , Ataque Isquémico Transitorio/fisiopatología , Imagen por Resonancia Magnética , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatología , Especificidad de la Especie
11.
Rofo ; 177(11): 1513-21, 2005 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-16302132

RESUMEN

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.


Asunto(s)
Aneurisma de la Aorta Torácica/diagnóstico , Disección Aórtica/diagnóstico , Imagen por Resonancia Magnética/métodos , Embolia Pulmonar/diagnóstico , Enfermedades Torácicas/diagnóstico , Enfermedad Aguda , Adulto , Anciano , Disección Aórtica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Artefactos , Diagnóstico Diferencial , Imagen Eco-Planar , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico por imagen , Radiografía Torácica , Estudios Retrospectivos , Enfermedades Torácicas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
12.
Stroke ; 32(2): 442-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11157180

RESUMEN

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.


Asunto(s)
Accidente Cerebrovascular/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal/métodos , Anciano , Edema Encefálico/etiología , Edema Encefálico/mortalidad , Edema Encefálico/prevención & control , Descompresión Quirúrgica , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/cirugía , Tasa de Supervivencia , Tercer Ventrículo/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X
13.
Stroke ; 34(9): 2234-9, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12920258

RESUMEN

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.


Asunto(s)
Maleato de Dizocilpina/uso terapéutico , Hipotálamo/fisiopatología , Fármacos Neuroprotectores/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/fisiopatología , Animales , Temperatura Corporal , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Fiebre/etiología , Fiebre/patología , Fiebre/prevención & control , Hipotálamo/patología , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/fisiopatología , Ligadura , Masculino , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/complicaciones , Titanio , Resultado del Tratamiento
14.
Stroke ; 35(2): 566-71, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14739415

RESUMEN

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.


Asunto(s)
Edema Encefálico/patología , Encéfalo/metabolismo , Accidente Cerebrovascular/patología , Agua/metabolismo , Animales , Encéfalo/irrigación sanguínea , Encéfalo/patología , Edema Encefálico/etiología , Edema Encefálico/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Imagen por Resonancia Magnética , Masculino , Variaciones Dependientes del Observador , Proyectos Piloto , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Accidente Cerebrovascular/complicaciones , Agua/análisis
15.
Stroke ; 31(10): 2342-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11022061

RESUMEN

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.


Asunto(s)
Circulación Cerebrovascular , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Activador de Tejido Plasminógeno/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/efectos de los fármacos , Arterias Carótidas/diagnóstico por imagen , Arterias Cerebrales/diagnóstico por imagen , Endarterectomía , Femenino , Humanos , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Accidente Cerebrovascular/etiología , Resultado del Tratamiento , Ultrasonografía Doppler en Color/métodos , Grado de Desobstrucción Vascular/efectos de los fármacos
16.
Neurology ; 52(6): 1133-7, 1999 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-10214733

RESUMEN

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.


Asunto(s)
Trastornos Cerebrovasculares/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Ultrasonografía Doppler Transcraneal/métodos , Adulto , Anciano , Arterias Cerebrales/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
17.
Neurology ; 52(1): 45-9, 1999 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-9921847

RESUMEN

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.


Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Infarto Cerebral/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Anciano de 80 o más Años , Arterias Cerebrales/fisiología , Infarto Cerebral/complicaciones , Infarto Cerebral/cirugía , Ventrículos Cerebrales/diagnóstico por imagen , Ventrículos Cerebrales/patología , Circulación Cerebrovascular/fisiología , Craneotomía , Descompresión Quirúrgica , Progresión de la Enfermedad , Femenino , Hernia/diagnóstico por imagen , Hernia/etiología , Herniorrafia , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Tomografía Computarizada por Rayos X
18.
Neurology ; 55(11): 1741-3, 2000 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-11113236

RESUMEN

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.


Asunto(s)
Enfermedad de Descompresión , Buceo , Embolia Aérea/fisiopatología , Adulto , Frío/efectos adversos , Embolia Aérea/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ultrasonografía Doppler
19.
AJNR Am J Neuroradiol ; 20(8): 1567-71, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10512247

RESUMEN

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.


Asunto(s)
Infarto de la Arteria Cerebral Media/diagnóstico , Hemorragias Intracraneales/diagnóstico , Tercer Ventrículo/patología , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler Transcraneal , Adulto , Anciano , Anciano de 80 o más Años , Cuidados Críticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad
20.
J Neuroimaging ; 6(4): 227-30, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8903074

RESUMEN

Transcranial color-coded duplex sonography is a recently introduced method for visualizing (1) the blood flow velocity of the basal cerebral arteries and (2) the brain parenchyma as an acoustic impedance image. Dislocation of the third ventricle due to space-occupying stroke is an important clinical marker. This study evaluated the dislocation of the third ventricle from the brain midline by transcranial duplex sonography in 10 healthy volunteers. The mean dislocation was 0.2 +/- 0.3 mm. Eighteen stroke patients were investigated within 12 hours by both duplex sonography and computed tomography (CT) and the dislocation of the third ventricle was measured. Correlation between the two methods was high (r = 0.87, N = 27). Twelve stroke patients divided into three subgroups according to the extent of the space-occupying effects of the lesion were followed for 3 weeks. The increase and decrease of the dislocation of the third ventricle over the time were monitored. In conclusion, transcranial duplex sonography is a reliable tool to monitor dislocation of the third ventricle due to space-occupying stroke.


Asunto(s)
Ventrículos Cerebrales/diagnóstico por imagen , Trastornos Cerebrovasculares/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal , Adulto , Velocidad del Flujo Sanguíneo , Edema Encefálico/diagnóstico por imagen , Arterias Cerebrales/diagnóstico por imagen , Hemorragia Cerebral/diagnóstico por imagen , Infarto Cerebral/diagnóstico por imagen , Ventriculografía Cerebral , Ecoencefalografía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Método Simple Ciego , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler en Color , Ultrasonografía Doppler Dúplex
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