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1.
Ultrasound Med Biol ; 26(5): 863-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10942833

RESUMO

Most three-dimensional (3-D) echocardiography (3-DE) systems today are based on off-line methods where a large number of cross-sectional 2-D scans have to be acquired sequentially before a 3-D image can be reconstructed. Because acquisition is done step-by-step based on ECG triggering plus respiratory gating, this introduces motion artefacts and takes significant acquisition time. Another 3-D approach is based on 2-D transducers and parallel beam-forming. Such a system is very complex. In this manuscript, a fast continuously-rotating scanning unit, based on a 64-element phased-array transducer, is described. Typical rotation speed of the 3-D unit is 8 rotations per s. Therefore, 16 3-D volume datasets can be acquired per s in real-time. The first clinical examples as acquired with this probe are presented.


Assuntos
Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Artefatos , Velocidade do Fluxo Sanguíneo/fisiologia , Ecocardiografia/instrumentação , Desenho de Equipamento , Humanos , Função Ventricular
2.
3.
Ultrasound Med Biol ; 22(1): 1-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8928306

RESUMO

After its introduction about two decades ago, transesophageal echocardiography (TEE) has rapidly evolved into an important diagnostic feature for the cardiologist, since it offers anatomic and hemodynamic information which cannot be obtained precordially. Part of this success was due to the developments in transducer technology which resulted in smaller probes with progressively better imaging qualities. A short review of past, recent and future developments of TEE phased array probes, in particular those at the Erasmus University in Rotterdam, will be given. Furthermore, this article discusses basic parameters of the transducer dictating image quality such as centre frequency, array aperture and focusing illustrated with several simulations. The simulations show that a poor design of the transducer will limit the resolution and will give artefacts in the two-dimensional image.


Assuntos
Ecocardiografia Transesofagiana , Cardiopatias/diagnóstico por imagem , Adulto , Criança , Ecocardiografia Transesofagiana/história , Ecocardiografia Transesofagiana/instrumentação , Desenho de Equipamento , História do Século XX , Humanos , Transdutores
4.
Am J Card Imaging ; 9(2): 79-86, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7795382

RESUMO

Early developments and basic principles in the field of Transesophageal Echocardiography (TEE) probe technology are summarized. Mechanical and electronical sector scanners are compared, and several probe characteristics and image parameters are discussed. A short review of recent developments in TEE is given.


Assuntos
Ecocardiografia Transesofagiana/instrumentação , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador , Transdutores
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