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1.
Rheumatology (Oxford) ; 39(11): 1206-13, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11085798

RESUMO

OBJECTIVE: We used colour Doppler ultrasound (CDU) to differentiate primary from secondary Raynaud's phenomenon (pRP and sRP, respectively) and to assess digital vascular damage in patients with connective tissue disease (CTD). METHODS: Vascularity in the nailbeds of 15 healthy controls and 35 patients with CTD (systemic sclerosis or systemic lupus erythematosus) was quantified using a multi-D array transducer before and after cold and warm challenge, respectively. The results were compared with the clinically evaluated initial skin lesions. Vascularity was compared similarly between 10 pRP and 22 sRP patients. RESULTS: Vascularity at ambient temperature differed between healthy subjects and sRP patients as well as between healthy subjects and CTD patients without initial skin lesions. Patients with pRP had normal vascularity at ambient temperature but differed from healthy controls in response to a dynamic temperature challenge. CDU confirmed the clinical evaluation in 89.4% of the patients with RP and in 78.0% of the skin lesions. CONCLUSION: The novel CDU technique presented here makes it possible to discriminate between pRP and sRP and to quantify vascular changes in CTD patients.


Assuntos
Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Doença de Raynaud/diagnóstico por imagem , Escleroderma Sistêmico/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adulto , Temperatura Baixa , Diagnóstico Diferencial , Feminino , Dedos/irrigação sanguínea , Temperatura Alta , Humanos , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/patologia , Masculino , Microcirculação , Pessoa de Meia-Idade , Artéria Radial , Doença de Raynaud/etiologia , Doença de Raynaud/patologia , Fluxo Sanguíneo Regional , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/patologia , Artéria Ulnar
2.
J Clin Ultrasound ; 28(9): 441-51, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11056021

RESUMO

PURPOSE: Color Doppler sonography has gained considerable recognition as a noninvasive method to detect carotid artery disease and to assess the degree of carotid artery stenosis. However, results are highly operator-dependent and cannot be presented as survey images. The purpose of this study was to evaluate real-time 3-dimensional (3D) power Doppler sonography as a method for screening for atherosclerosis in the carotid arteries. METHODS: We prospectively screened 75 patients for carotid artery disease using both conventional color Doppler sonography and 3D power Doppler sonography, and the results from the 2 modalities were compared. A total of 150 common carotid arteries, 150 internal carotid arteries, and 150 external carotid arteries were examined utilizing a 7.5-MHz linear-array transducer combined with tissue harmonic imaging. RESULTS: Color Doppler sonography detected 297 normal or atherosclerotic arteries without stenosis, 57 arteries with mild (1-49%) stenosis, 41 with moderate (50-69%) stenosis, 32 with severe (70-99%) stenosis, and 9 with occlusions. The degree of stenosis determined by color Doppler sonography correlated with that determined by 3D power Doppler sonography (r = 0.982-0.998). Moreover, there was a good correlation between the measurements for both the length of the lesion and its distance from the bulb as determined by the 3D volume surveys and by color Doppler sonography (r = 0.986). The interobserver variability rate was 3.7% +/- 0.5%. Generally, the acquisition and reconstruction of the 3D data took less than 5 minutes. CONCLUSIONS: 3D power Doppler sonography is easy to perform and is an accurate method in screening for atherosclerotic lesions of the carotid arteries. Moreover, it provides excellent 3D volume surveys that may be helpful in the planning of surgical treatment.


Assuntos
Doenças das Artérias Carótidas/diagnóstico por imagem , Imageamento Tridimensional , Programas de Rastreamento , Ultrassonografia Doppler , Idoso , Idoso de 80 Anos ou mais , Doenças das Artérias Carótidas/classificação , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Externa/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Transdutores , Ultrassonografia Doppler/instrumentação , Ultrassonografia Doppler em Cores/instrumentação
3.
Eur Radiol ; 10(7): 1043-50, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11003395

RESUMO

The aim of this study was to compare the latest ultrasound-array technology to a conventional "high-resolution" transducer, modified MRI technique, and nerve conduction studies (NCS), in the diagnosis of carpal tunnel syndrome (CTS). In 19 normal wrists and 15 wrists with CTS, US with two different transducers was performed: a conventional linear-array transducer (LA) and a newly developed Multi-D linear-array transducer (MDA) were used. The US images were evaluated determining the swelling and the flattening ratios of the median nerve and correlated to respective findings in MRI (1.5 T) and to NCS. The NCS confirmed CTS in all 15 wrists. Measures of median nerve compression (swelling and flattening ratios) were significantly different in patients with CTS and controls (p < 0.01) with both types of US transducers and MRI. The MDA yielded higher correlation to MRI than the LA. Using critical values of 1.3 for the swelling and 3.4 for the flattening ratio, MRI, and US with the MDA yielded a sensitivity of 100% each. Modern imaging modalities allow for an exact diagnosis of CTS even in cases with only slight median nerve pathology.


Assuntos
Síndrome do Túnel Carpal/diagnóstico por imagem , Síndrome do Túnel Carpal/patologia , Imageamento por Ressonância Magnética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
4.
Ultraschall Med ; 21(1): 26-31, 2000 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-10746281

RESUMO

AIM: To evaluate a novel 3D power Doppler ultrasound-technique (3D PDUS) in the diagnosis and documentation of tumours of the floor of the mouth. METHOD: 22 patients with tumours of the floor of the mouth (2 T1-, 5 T2-, 6 T3- and 9 T4-carcinomas) prospectively underwent conventional grey-scale ultrasound combined with power Doppler ultrasound and 3D PDUS (3-Scape). All examinations were performed with the "Sonoline Elegra Advanced" in combination with a 7.5 MHz transducer. Two independent observers compared the results regarding clear tumour margins, midline crossing, infiltration of the mylohyoid muscle, infrahyoidal tumour, contact to the mandible, contact to major vessels (such as the lingual, submental and/or facial artery), intra- and peritumoural vascularisation and judged the value of the 3D reconstruction method for documentation purpose. RESULTS: All parameters relevant for therapy could be gathered from the 3D data (agreement: 98.2%) almost without loss of information; results of both observers were identical (kappa value: 1.0). In the comparison to conventional ultrasound, 3D PDUS also allows for the reconstruction of axial images of the floor of the mouth similar to CT-images, and a 3D image of tumour vascularisation can be obtained. Acquisition and reconstruction of the 3D data only takes a couple of minutes. CONCLUSIONS: "3-Scape" is a novel easy-to-perform method allowing the complete acquisition of 3D data of the entire floor of the mouth, and providing the possibility to digitally store and/or transfer examination results without loss of information. Reconstruction of ultrasound-images in any desirable plane and/or as a 3D presentation is possible. Thus, in the future, additional software will facilitate the determination of the volume and the degree of vascularisation of tumours.


Assuntos
Neoplasias Bucais/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Adulto , Idoso , Documentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/irrigação sanguínea , Neoplasias Bucais/patologia , Invasividade Neoplásica , Estadiamento de Neoplasias , Variações Dependentes do Observador
5.
Arthritis Rheum ; 42(11): 2303-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10555024

RESUMO

OBJECTIVE: To evaluate the extent of intraarticular vascularization and pannus formation in metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints of patients with rheumatoid arthritis (RA) by high-resolution ultrasound (US). METHODS: A newly developed, high-resolution multidimensional linear array US was utilized to obtain longitudinal and transverse scans of joints with active RA (n = 21), moderately active RA (n = 39), or inactive RA (n = 93), and of joints from healthy controls (n = 120). RESULTS: Healthy joints had no detectable pannus, whereas pannus could be detected in 52% of the joints with active RA, 82% of the joints with moderately active RA, and 67% of the joints with inactive RA. There was a significant difference in vascularization in the joints of all subgroups of RA patients and those of healthy subjects (P < 0.001). Moreover, vascularization differed significantly among the RA subgroups: inactive versus moderately active RA (P < 0.02) and inactive versus active RA (P < 0.05). Both pannus and vascularization appeared to be localized preferentially on the radial side of the joints. CONCLUSION: Evaluation of pannus and the extent of vascularization within the joints of patients with RA by high-resolution US might be helpful in the assessment of disease activity, and thus influence therapeutic strategies.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Articulação Metacarpofalângica/diagnóstico por imagem , Ultrassonografia/métodos , Adulto , Idoso , Artrite Reumatoide/patologia , Estudos Transversais , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Articulação Metacarpofalângica/irrigação sanguínea , Articulação Metacarpofalângica/patologia , Pessoa de Meia-Idade , Neovascularização Patológica
7.
Radiologe ; 38(5): 410-6, 1998 May.
Artigo em Alemão | MEDLINE | ID: mdl-9646349

RESUMO

Through high-performance computer processing it has become possible to realize a new ultrasound imaging process: SieScape imaging. This method provides extended field of view images in real time using successive ultrasound images obtained when a standard transducer is scanned over a distance of up to 60 cm without any position sensor. SieScape offers new possibilities to view topographical anatomy. It is especially advantageous for scanning extended and tubular structures as well as large and enlarged organs and big pathologic volumes. Parallel scanning sequences allow documentation comparable to that of computed tomography. In addition, just as in magnetic resonance, variable imaging planes can be realized. The following describes the results obtained with SieScape in a multitude of clinical applications, especially in examinations of throat, thoracic and abdominal walls, breast, and intraabdominal organs as well as the soft tissues and small vessels of the extremities. The experience gathered with SieScape imaging--its advantages as well as its potential limitations, such as the formation of artefacts--is described.


Assuntos
Aumento da Imagem/instrumentação , Processamento de Imagem Assistida por Computador/instrumentação , Ultrassonografia/instrumentação , Desenho de Equipamento , Humanos , Sensibilidade e Especificidade , Transdutores
8.
Ultraschall Med ; 14(5): 225-30, 1993 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-8256123

RESUMO

Various colour flow imaging techniques for diagnostic ultrasound have been reported in the literature, each claiming distinctive performance characteristics for the benefit of the user. The following is a review of the principles of autocorrelation, autoregression (or maximum entropy), and of cross-correlation methods. All three approaches are based on the same principle of physics, i.e. the analysis of echoes backscattered from red blood cells of fluctuating density due to motion, but differ in their sampling requirements and in signal processing. A comparison of major performance features and challenges is given.


Assuntos
Hemodinâmica/fisiologia , Processamento de Imagem Assistida por Computador/instrumentação , Ultrassonografia/instrumentação , Algoritmos , Velocidade do Fluxo Sanguíneo/fisiologia , Interpretação Estatística de Dados , Análise de Fourier , Humanos
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