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1.
Int J Endocrinol ; 2017: 3946569, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28852407

RESUMO

OBJECTIVE: It is highly debated whether associations between osteoporosis and atherosclerosis are independent of cardiovascular risk factors. We aimed to explore the associations between quantitative ultrasound (QUS) parameters at the heel with the carotid artery intima-media thickness (IMT), the presence of carotid artery plaques, and the ankle-brachial index (ABI). METHODS: The study population comprised 5680 men and women aged 20-93 years from two population-based cohort studies: Study of Health in Pomerania (SHIP) and SHIP-Trend. QUS measurements were performed at the heel. The extracranial carotid arteries were examined with B-mode ultrasonography. ABI was measured in a subgroup of 3853 participants. Analyses of variance and linear and logistic regression models were calculated and adjusted for major cardiovascular risk factors. RESULTS: Men but not women had significantly increased odds for carotid artery plaques with decreasing QUS parameters independent of diabetes mellitus, dyslipidemia, and hypertension. Beyond this, the QUS parameters were not significantly associated with IMT or ABI in fully adjusted models. CONCLUSIONS: Our data argue against an independent role of bone metabolism in atherosclerotic changes in women. Yet, in men, associations with advanced atherosclerosis, exist. Thus, men presenting with clinical signs of osteoporosis may be at increased risk for atherosclerotic disease.

2.
Gesundheitswesen ; 77(2): e20-5, 2015 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-25714194

RESUMO

OBJECTIVE: This study describes (i) the procedure of obtaining patients' consent for secondary data usage, (ii) the complexity of integrating data from multiple sources, and (iii) the correspondence among patients' self-reports, physician reports, routine data, hospital discharge diagnosis, and cause-of-death coding regarding stroke. METHODS: Data from the first follow-up (N=3 186) of the population-based Study of Health in Pomerania (SHIP) were used. These data were combined with secondary data from the Greifswald University Hospital, the association of statutory health insurance physicians Mecklenburg-Western Pomerania, physician reports, and death certificates. RESULTS: Consent for using health-related information from all data sources in question was obtained from more than 90% of the SHIP participants. Follow-up data from at least one source were available for 2 747 (86%) participants. For 92 participants information about the occurrence of stroke was found in at least one data source. In 59 cases the event appeared in only one data source, in 24 cases the event was found in 2 sources, and for 9 participants 3 data sources reported on the event. CONCLUSION: Participants of a population-based cohort are highly willing to give consent for using their health-related information from secondary data sources. Yet, data integration is challenging due to considerable differences in data type, structure and coverage.


Assuntos
Hospitalização/estatística & dados numéricos , Consentimento Livre e Esclarecido/estatística & dados numéricos , Registro Médico Coordenado/métodos , Sistemas Computadorizados de Registros Médicos/estatística & dados numéricos , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/terapia , Confiabilidade dos Dados , Estudos de Viabilidade , Alemanha/epidemiologia , Humanos , Armazenamento e Recuperação da Informação/estatística & dados numéricos , Uso Significativo/estatística & dados numéricos , Programas Nacionais de Saúde/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Prevalência , Acidente Vascular Cerebral/diagnóstico , Taxa de Sobrevida , Integração de Sistemas , Resultado do Tratamento
4.
Med Klin Intensivmed Notfmed ; 108(2): 131-8, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23070330

RESUMO

BACKGROUND: This article gives an up-to-date overview of neurosonographic emergency and intensive care diagnostics. METHODS: Selective literature research from 1984 with critical appraisal and including national and international guidelines. RESULTS: Fast and valid diagnostics in acute stroke is the main field of application of neurosonography. Specific monitoring methods bear great advantages for intensive care patients, especially "as-often-as-wanted" repetitive imaging under real-time conditions. A number of new developments make neurosonography an interesting area of research. CONCLUSIONS: Neurosonography has played a key role in neurological emergency and intensive care medicine for many years. It remains important to continuously support dissemination of the method.


Assuntos
Morte Encefálica/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Cuidados Críticos , Ecoencefalografia , Serviço Hospitalar de Emergência , Aneurisma Intracraniano/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Ultrassonografia , Insuficiência Vertebrobasilar/diagnóstico por imagem , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/terapia , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Dissecação da Artéria Carótida Interna/terapia , Estenose das Carótidas/terapia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/terapia , Diagnóstico Diferencial , Humanos , Aneurisma Intracraniano/terapia , Monitorização Fisiológica , Sensibilidade e Especificidade , Acidente Vascular Cerebral/terapia , Trombectomia , Terapia Trombolítica , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Transcraniana , Ultrassonografia de Intervenção , Insuficiência Vertebrobasilar/terapia
5.
Cerebrovasc Dis ; 34(4): 290-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23128470

RESUMO

Intima-media thickness (IMT) provides a surrogate end point of cardiovascular outcomes in clinical trials evaluating the efficacy of cardiovascular risk factor modification. Carotid artery plaque further adds to the cardiovascular risk assessment. It is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. The scientific basis for use of IMT in clinical trials and practice includes ultrasound physics, technical and disease-related principles as well as best practice on the performance, interpretation and documentation of study results. Comparison of IMT results obtained from epidemiological and interventional studies around the world relies on harmonization on approaches to carotid image acquisition and analysis. This updated consensus document delineates further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT. Standardized methods will foster homogenous data collection and analysis, improve the power of randomized clinical trials incorporating IMT and plaque measurements and facilitate the merging of large databases for meta-analyses. IMT results are applied to individual patients as an integrated assessment of cardiovascular risk factors. However, this document recommends against serial monitoring in individual patients.


Assuntos
Artérias Carótidas/patologia , Espessura Intima-Media Carotídea , Acidente Vascular Cerebral/patologia , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Artérias Carótidas/diagnóstico por imagem , Humanos , Placa Aterosclerótica/diagnóstico , Placa Aterosclerótica/diagnóstico por imagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico por imagem
6.
Ultraschall Med ; 33(4): 320-31; quiz 332-6, 2012 Aug.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-22833201

RESUMO

Transcranial B-mode sonography is an easy to use bedside imaging modality to monitor significant changes of the brain parenchyma such as in malignant middle cerebral infarction or intracerebral hemorrhage. The elevation of intracranial pressure can be followed with various neurosonographical techniques: Measurements of the ventricular width, midline shift, arterial resistance, and optic nerve sheath diameter. They should be viewed as complementary to each other and to other imaging modalities. Repeated cCT and MRI may be avoided in unstable patients by bedside neurosonography in the hands of an experienced physician. Monitoring of evolving hydrocephalus using serial measurements of the third and lateral ventricles can be used to guide therapeutic decisions such as the removal of a ventricular drainage. The cessation of cerebral blood flow in the case of intracranial pressure exceeding systemic arterial pressure is an important part of brain death diagnostics. Early demonstration of a sufficient temporal bone window is needed in patients in whom brain death may be expected. Cerebrovascular autoregulation is an integer component of the brain's blood supply and is compromised in a variety of neurological diseases. In neurological/neurosurgical patients in the intensive care unit, its assessment allows for extended neuromonitoring and control of therapeutic procedures.


Assuntos
Morte Encefálica/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Ecoencefalografia/métodos , Serviço Hospitalar de Emergência , Homeostase/fisiologia , Unidades de Terapia Intensiva , Hipertensão Intracraniana/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Humanos , Monitorização Fisiológica , Sensibilidade e Especificidade
8.
Clin Neurol Neurosurg ; 114(6): 627-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22236827

RESUMO

BACKGROUND: Although randomized clinical trials have reported significant improvement in mortality and functional outcome as measured with modified Rankin Scale (mRS) or Barthel index (BI) in stroke patients with space-occupying anterior circulation infarctions treated with hemicraniectomy, many clinicians are still concerned about the long-term health-related quality of life (HRQoL). AIM: Assessment of HRQoL after hemicraniectomy to holistically reevaluate clinical outcome. METHODS: Eleven patients (6 men, 5 women; mean age 48 (SD 5.8) years) were examined at 9-51 months after hemicraniectomy. Test batteries comprised NIH stroke scale, BI, mRS, neuropsychological tests (Visual Object and Space Perception Battery and clock test), and HRQoL-scales (Short Form 36 Health Survey (SF-36), Nottingham Health Profile (NHP), Questions on Life Satisfaction, Hospital Anxiety and Depression Scale and EQ-5D). RESULTS: Median values for NIHSS, BI and mRS were 11.5, 55 and 3.5. In HRQoL-scales, subscales related to physical mobility and functioning were consistently severely impaired, while subscales related to psychological well-being were impaired to a lesser extent. Mean scores for physical functioning and physical role were 10.5 and 12.5 in the SF-36, and 61.3 and 43.3 for physical mobility and energy in the NHP; emotional role and mental health scored 63.3 and 66.4 (SF-36), scores for emotional reaction and social isolation were 18.9 and 16.0 (NHP), respectively. CONCLUSION: Although, physical components of HRQoL are highly impaired, these stroke patients achieved a satisfying level of psychological well-being which was endorsed by a nearly unanimous retrospective appraisal of life-saving hemicraniectomy.


Assuntos
Edema Encefálico/psicologia , Edema Encefálico/cirurgia , Descompressão Cirúrgica/psicologia , Procedimentos Neurocirúrgicos/psicologia , Qualidade de Vida/psicologia , Acidente Vascular Cerebral/psicologia , Acidente Vascular Cerebral/cirurgia , Adulto , Idoso , Ansiedade/etiologia , Ansiedade/psicologia , Infarto Cerebral/cirurgia , Craniotomia , Depressão/etiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Testes Neuropsicológicos , Satisfação Pessoal , Estudos Retrospectivos , Isolamento Social , Reabilitação do Acidente Vascular Cerebral , Resultado do Tratamento
9.
Acta Neurol Scand ; 126(3): 171-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22077692

RESUMO

INTRODUCTION: It is crucial to understand the reasons behind pre- and in-hospital delays to improve nationwide access to effective treatment for acute stroke. AIMS: To evaluate the pre- and in-hospital delays and to compare the intravenous (IV) thrombolysis rates in the urban and rural areas of the Province of Pomerania, Poland. MATERIALS & METHODS: We evaluated the medical records of 2134 patients treated in the stroke units (SUs) and consecutively reported to the Pomeranian Stroke Register from June 2006-December 2007. RESULTS: The time of ischaemic stroke onset was known in 488 (59%) of the 834 urban patients and in 744 (70%) of the 1063 rural patients (P < 0.001). The proportion of patients who called the emergency medical services with a delay of >45 min was similar in both locations: urban, 314/488 (64.3%) vs rural, 490/744 (65.8%). Although the proportion of patients who reached the emergency room within 3 h was higher in the rural areas (29.0% vs 24.3%; P = 0.02), only 4.2% of these patients received IV thrombolysis compared with 23.1% in the urban areas (P < 0.001). The proportion of patients who did not seek any kind of professional medical help prior to admission was lower in the rural areas (29/744 (3.9%) vs urban 50/488 (10.2%)) (P < 0.001). CONCLUSIONS: Pre-hospital delays reduced the number of patients eligible for IV thrombolysis in both rural and urban areas. The low proportion of patients treated with IV thrombolysis in rural SUs may be attributed to ineffective in-hospital procedures.


Assuntos
Fibrinolíticos/administração & dosagem , Hospitalização , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , População Rural , Acidente Vascular Cerebral/epidemiologia , Fatores de Tempo , População Urbana
10.
Clin Radiol ; 64(11): 1097-103, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19822243

RESUMO

AIM: To investigate the gender differences associated with a thinner intima-media thickness (IMT) of the common carotid artery (CCA) in women. MATERIALS AND METHODS: In a sample of 218 consecutive healthy volunteers comprising 110 men and 108 women, the IMT of the CCA was measured using B-mode ultrasonography. Blood pressure, fasting blood sugar, body mass index (BMI), blood lipid profile, homocysteine, folic acid, uric acid, high sensitive C-reactive protein, and thiobarbituric acid reactive substances (TBARS) levels were measured and compared with each other in both genders. RESULTS: The IMT of the CCA was significantly thinner in women than in men (p=0.012). Blood pressure, fasting plasma glucose, BMI, low-density lipoprotein cholesterol, triglycerides, homocysteine, uric acid, and TBARS were significantly (p<0.05) lower, folic acid and high-density lipoprotein cholesterol (HDL-C) were significantly (p<0.0001) higher in women compared with men. Multivariable logistic regression analysis revealed that higher serum levels of homocysteine, uric acid, and TBARS, and lower serum levels of HDL-C were significantly (p<0.05) associated with male sex. Multiple linear regression analysis further revealed that age, sex, and BMI were independently associated with CCA IMT. CONCLUSIONS: The IMT of the CCA was thinner in women than in men. Traditional vascular risk factors explain only a small amount of variance in multivariate regression models supporting the hypothesis that other behavioural, sex hormone-related or genetic factors, which have not been sufficiently explored so far, may play a role in the gender differences of IMT.


Assuntos
Artéria Carótida Primitiva , Túnica Média , Adulto , Fatores Etários , Idoso , Biomarcadores/sangue , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa/análise , Artéria Carótida Primitiva/anatomia & histologia , Artéria Carótida Primitiva/diagnóstico por imagem , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco , Fatores Sexuais , Triglicerídeos/sangue , Túnica Média/anatomia & histologia , Túnica Média/diagnóstico por imagem , Ultrassonografia , Adulto Jovem
11.
Cerebrovasc Dis ; 28(4): 349-56, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19628936

RESUMO

BACKGROUND: Right-to-left cardiac shunt (RLS) is considered a risk factor for stroke, especially in patients aged <55 years. We aimed to investigate the current management and prognosis in consecutive patients with RLS and otherwise cryptogenic cerebrovascular events. METHODS: In total, 1,126 patients with cryptogenic stroke or TIA were included from 17 German neurology departments. During a mean follow-up of 28.4 months, we assessed current antithrombotic medication, percutaneous device closure (PDC) and recurrent cerebrovascular events in 899 patients (79.8%). Stroke recurrence was compared between 548 patients without RLS and 351 patients with RLS under various prevention regimens. RESULTS: RLS was detected in 35.9% of cryptogenic cerebrovascular patients, but could not be evaluated as an independent predictor for recurrent stroke (adjusted HR 1.6, 95% CI: 0.9-2.7). In RLS-positive patients, the Kaplan-Meier estimate for stroke during the first year was 4.1% (95% CI: 1.9-6.3%) and 1.7% (95% CI: 0.9-2.4%) per year thereafter. At the last follow-up before recurrent stroke or end of study, 117 RLS-positive patients (33.3%) had received a PDC, 154 (43.9%) were receiving antiplatelets, 63 (17.9%) received anticoagulation, and 17 (4.8%) received none of the above. No association with recurrent stroke was found for the secondary preventive regime. CONCLUSION: Our multicenter hospital-based cohort study confirmed low recurrent event rates in RLS patients with otherwise cryptogenic stroke or TIA, as well as a great heterogeneity of current management. Despite the lack of scientific evidence, a substantial number of RLS-positive patients underwent PDC for secondary stroke prevention.


Assuntos
Anticoagulantes/uso terapêutico , Cateterismo Cardíaco , Circulação Coronária , Forame Oval Patente/terapia , Ataque Isquêmico Transitório/terapia , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/terapia , Cateterismo Cardíaco/instrumentação , Feminino , Seguimentos , Forame Oval Patente/complicações , Forame Oval Patente/mortalidade , Forame Oval Patente/fisiopatologia , Alemanha , Humanos , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/mortalidade , Ataque Isquêmico Transitório/fisiopatologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Prevenção Secundária , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
12.
Cerebrovasc Dis ; 23(1): 75-80, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17108679

RESUMO

Intima-media thickness (IMT) is increasingly used as a surrogate end point of vascular outcomes in clinical trials aimed at determining the success of interventions that lower risk factors for atherosclerosis and associated diseases (stroke, myocardial infarction and peripheral artery diseases). The necessity to promote further criteria to distinguish early atherosclerotic plaque formation from thickening of IMT and to standardize IMT measurements is expressed through this updated consensus. Plaque is defined as a focal structure that encroaches into the arterial lumen of at least 0.5 mm or 50% of the surrounding IMT value or demonstrates a thickness >1.5 mm as measured from the media-adventitia interface to the intima-lumen interface. Standard use of IMT measurements is based on physics, technical and disease-related principles as well as agreements on how to perform, interpret and document study results. Harmonization of carotid image acquisition and analysis is needed for the comparison of the IMT results obtained from epidemiological and interventional studies around the world. The consensus concludes that there is no need to 'treat IMT values' nor to monitor IMT values in individual patients apart from exceptions named, which emphasize that inside randomized clinical trials should be performed. Although IMT has been suggested to represent an important risk marker, according to the current evidence it does not fulfill the characteristics of an accepted risk factor. Standardized methods recommended in this consensus statement will foster homogenous data collection and analysis. This will help to improve the power of randomized clinical trials incorporating IMT measurements and to facilitate the merging of large databases for meta-analyses.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Doenças das Artérias Carótidas/complicações , Ensaios Clínicos como Assunto/métodos , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Projetos de Pesquisa , Fatores de Risco , Ultrassonografia/métodos , Ultrassonografia/normas
13.
J Neuroimaging ; 12(3): 245-51, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12116743

RESUMO

BACKGROUND AND PURPOSE: Lowering of serum cholesterol levels with HMG-CoA reductase inhibitors (statins) slowed the progression of atherosclerosis in the carotid arteries in several clinical trials using carotid artery intima media thickness as primary outcome measure. Whereas conventional ultrasonography is limited to thin 2-dimensional image planes, 3-dimensional (3D) ultrasonography provides quantitative measurement of the entire carotid artery plaque volume. This study aims to assess the feasibility of 3D ultrasonography to monitor plaque progression in hypercholesterolemic patients. METHODS: The authors prospectively assessed the progression of 31 carotid artery plaques over 15.1 +/- 4.5 months in a study of 23 patients (6 women, 17 men; mean age = 61.7 +/- 7.5 years) with hypercholesterolemia under therapy with HMG-CoA reductase inhibitors. All patients were maintained on a lipid-lowering diet. Sixteen patients were additionally treated with statins. Quantitative measurements of carotid artery plaque volumes were performed after 3D reconstruction of exactly parallel transverse duplex ultrasound scans (slice distance = 0.1 mm) into volumetric 3D data sets and segmentation of voxels representing the carotid artery plaque. RESULTS: Within the treatment group, plaques were significantly less frequently progressive if they had a hypoechoic echogenicity (11%, n = 9 vs 64%, n = 14; P = .016) or if baseline serum cholesterol levels were above 8.0 mmol/L (9%, n = 11 vs 75%, n = 12; P = .002). CONCLUSION: Three-dimensional ultrasonography extends the measurement of the arterial wall thickness to the 3D volume of an entire atherosclerotic plaque including analysis of its morphology and configuration. However, further clinical trials with an adequate sample size to achieve sufficient statistical power are necessary to assess the effect of statin therapy on plaque progression.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Doenças das Artérias Carótidas/tratamento farmacológico , Estudos de Casos e Controles , Colesterol/sangue , Estudos de Viabilidade , Feminino , Humanos , Hipercolesterolemia/diagnóstico por imagem , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Inibidores da Agregação Plaquetária/uso terapêutico , Ultrassonografia
14.
J Neuroimaging ; 11(4): 435-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11677886

RESUMO

Bilateral symmetrical cerebellar infarcts in the territory supplied by the medial posterior inferior cerebellar artery (PICA) branches are extremely rare. In the few cases published, it has not been possible to clearly pinpoint the cause of this infarct pattern. The authors present the case history of a 58-year-old man who had acute headaches accompanied by pronounced rotatory vertigo with nausea and vomiting. The neurological examination revealed bilateral cerebellar signs. Cranial magnetic resonance imaging showed bilateral, nearly symmetrical infarcts in the territory of the medial branches of both PICAs. These bilateral PICA infarctions were caused by a stenosis of an unpaired PICA originating from the left vertebral artery supplying both cerebellar hemispheres.


Assuntos
Arteriopatias Oclusivas/complicações , Doenças Cerebelares/etiologia , Cerebelo/irrigação sanguínea , Artérias Cerebrais/anormalidades , Infarto Cerebral/etiologia , Arteriopatias Oclusivas/diagnóstico , Doenças Cerebelares/diagnóstico , Infarto Cerebral/diagnóstico , Diagnóstico por Imagem , Humanos , Masculino , Pessoa de Meia-Idade
16.
Neuroradiology ; 43(1): 24-8, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11214643

RESUMO

Since the introduction of contrast media, transcranial colour-coded sonography (TCCS) has become increasingly important for examination of the intracranial vessels. However, the widely practised bolus injection of these agents leads to initial blooming artefacts and thereafter the level of contrast enhancement decreases rapidly, reducing the effective time of enhancement. It was our aim to investigate the effect of continuous administration of contrast medium at a defined infusion rate. We performed 28 TCCS examinations of the intracranial vessels in 26 patients using a 2.25 MHz phased-array transducer during administration of 4 g Levovist (Schering, Berlin, Germany) 300 mg/ml with a constant infusion rate of 60 ml/h into an antecubital vein. The degree of enhancement was graded over time in a subjective analysis by two independent observers. During continuous administration, a constant level of contrast enhancement was reached after 60.1+/-26.2 s and this lasted 663.4+/-55.8 s as assessed by the first observer (66.6+/-26.2 s and 664.3+/-55.9 s according to the second observer). The limits of inter-observer agreement ranged from -10.1% to 9.9%. No major blooming effect was seen in the initial phase of the examination.


Assuntos
Encéfalo/irrigação sanguínea , Transtornos Cerebrovasculares/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Polissacarídeos , Ultrassonografia Doppler Transcraniana , Artefatos , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Polissacarídeos/administração & dosagem , Estudos Prospectivos , Fatores de Tempo
17.
J Neuroimaging ; 10(3): 173-6, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10918745

RESUMO

Because examinations of the intracranial vessels using conventional transcranial color-coded sonography (TCCS) lack spatial orientation and reproducibility, development of a three-dimensional (3-D) imaging technique is required. Three patients with middle cerebral artery (MCA) stenosis, three with suspected intracranial aneurysm, two with vascular malformation, and one healthy volunteer were investigated by 3-D TCCS using a magnetic spatial positioning sensor mounted on the transducer for simultaneous recording of the probe coordinates to create a volumetric data set. Three-dimensional transcranial color-coded sonography enabled good visualization of intracranial aneurysms and MCA stenoses. However, it failed to detect morphological details in vascular malformations. In conclusion, 3-D TCCS is a promising technique that opens new perspectives in depicting intracranial vessels and provides volume measurement of intracranial aneurysms.


Assuntos
Doenças Arteriais Cerebrais/diagnóstico por imagem , Círculo Arterial do Cérebro/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Transcraniana , Adulto , Idoso , Constrição Patológica/diagnóstico por imagem , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
18.
Stroke ; 31(7): 1651-5, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10884468

RESUMO

BACKGROUND AND PURPOSE: Carotid artery plaque ulceration is associated with an increased risk of cerebral embolism. However, because of the rather poor diagnostic quality of conventional 2-D ultrasound and angiography compared with the evaluation of pathological specimens, little information exists on the natural course of carotid plaque ulceration. Recently, the introduction of 3-D ultrasound has made reproducible investigation of plaque morphology possible, providing a reliable plaque surface analysis. METHODS: We performed 3-D ultrasound examinations of 17 carotid artery plaques with an ulcerated surface in a prospective study of 16 patients (10 men, 6 women; mean+/-SD age 68.9+/-7.1 years) over a mean observation period of 17.6+/-6.3 months. Exactly parallel B-mode ultrasound scans (slice distance 0.1 mm) were acquired with a 5-MHz linear array probe clamped in a carriage device and driven by a mechanical step motor. The recorded images were reconstructed into a volumetric data set in a Cartesian coordinate system. RESULTS: At the end of the observation period, surface configuration had changed in 4 cases (23.5%). Plaque ulceration regressed in 3 cases, whereas ulcer progression occurred in 1 case. The remaining 13 plaques (76. 5%) showed an unchanged surface configuration. CONCLUSIONS: Through the use of 3-D ultrasound, it is possible to noninvasively examine the regression and progression of carotid artery plaque ulceration.


Assuntos
Artérias Carótidas/patologia , Doenças das Artérias Carótidas/patologia , Úlcera/patologia , Ultrassonografia/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/normas , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Reprodutibilidade dos Testes , Ultrassonografia/normas
19.
J Neurol ; 247(2): 106-11, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10751112

RESUMO

Elucidation of the dynamic nature of plaque progression has important implications for clinicians. The present study sought to establish an in vivo method for visualizing structural changes in carotid plaques. Three-dimensional reconstruction of parallel two-dimensional gray-scale B-mode ultrasound combined with power-mode examination of 38 carotid artery plaques was performed in a prospective study of 32 patients (18 men, 14 women; mean age 67.5 +/- 7.6 years). Initial mean plaque volume was 391 microl. After a mean of 18.9 months carotid artery plaque progression had occurred in 15% of carotid artery plaques, with plaque volume increasing 59% in these cases. Plaque volume remained constant, within a range of +/- 20% in 85% of cases. Progressive plaques were predominantly hypoechoic (3/5 cases) or had an ulcerated surface in cases of a hyperechoic echogenicity (2/5 cases). Risk factors and drug therapy were unrelated to plaque progression. This study illustrates that the combination of three-dimensional ultrasound with power-mode imaging improves the separation of the intraluminal plaque surface from the vessel lumen. Three-dimensional reconstruction of atherosclerotic carotid artery plaques enables the reproducible quantification of plaque volume and is therefore an excellent technique for longitudinal trials assessing progression or regression of carotid artery disease.


Assuntos
Arteriosclerose/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , Arteriosclerose/fisiopatologia , Doenças das Artérias Carótidas/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Estudos Prospectivos
20.
Neuroradiology ; 40(8): 490-5, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9763335

RESUMO

The main limitation of transcranial colour-coded duplex sonography (TCCD) is the inadequate acoustic window, which prevents transtemporal identification of the basal cerebral arteries in up to 30% of cases, especially in the elderly. TCCD with different colour-coding techniques, including frequency-based colour-flow (CFD) or power (PD) Doppler sonography, used alone or in combination with contrast media, were used in 23 patients with middle cerebral artery (MCA) stenosis. In 10 patients a contrast medium (400 mg/ml SHU 508 A) was administered because of inadequate colour-coded visualisation with TCCD. The data were compared with angiographic methods. Digital subtraction angiography (DSA) revealed 2 low-grade, 11 middle-grade and 10 high-grade stenoses in the M1 segment. With TCCD, we found a 7.7% higher blood flow velocity (systolic peak velocity) than with transcranial duplex sonography without colour-coding because of visual angle correction and a 20% higher systolic peak velocity using contrast enhancement. CFD did not differ from PD in identification of low- and middle-grade MCA stenoses, but PD alone revealed two more cases of high-grade stenosis than CFD. The contrast medium increased diagnostic confidence in 8 of 10 cases. Only 2 of 23 MCA stenoses (9%) could not be shown using TCCD.


Assuntos
Transtornos Cerebrovasculares/diagnóstico por imagem , Meios de Contraste , Ataque Isquêmico Transitório/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Ultrassonografia Doppler Transcraniana , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Artérias Cerebrais/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
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