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1.
Ultrasound Med Biol ; 43(6): 1195-1204, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28385470

RESUMO

It is known from physiology that heartbeat and respiration influence venous return, but little is known regarding the extent to which these two factors affect flow. In this study, we estimated the prevalence of cardiac- and breathing-induced venous flow modulations in the internal jugular vein (IJV) and vertebral vein (VV) and the effects of posture. In 19 healthy patients, neck vein flow was examined with pulsed wave Doppler. Electrocardiogram and respiratory signals were simultaneously acquired. In supine position, heart contraction always influenced venous flow, whereas breathing influenced 68% of IJV and 34% of VV flow. In sitting position, heart contraction influenced 74% of IJV and 42% of VV flow; breathing influenced 68% of IJV and 61% of VV measures. Thus, cardiac influence is greatly present in supine position, whereas breathing influence prevails in the VV while sitting. This setup allowed us to observe that in some patients, expiration may cause an unexpected increase in venous flow.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Frequência Cardíaca/fisiologia , Veias Jugulares/fisiologia , Contração Miocárdica/fisiologia , Postura/fisiologia , Mecânica Respiratória/fisiologia , Adolescente , Adulto , Ecocardiografia Doppler de Pulso/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
2.
Artigo em Inglês | MEDLINE | ID: mdl-24109957

RESUMO

Breast examination both for screening and second level of investigation has spread worldwide, due to increased breast cancer awareness. Thus, different diagnostic imaging technologies emerged in breast application. Ultrasound (US), a real-time examination, non-invasive, cost effective, ideal also for repetitive follow-up and able to give information about anatomy, hemodynamics and tissue stiffness, plays an important role in breast diagnostics. The present work describes the innovative three-dimensional (3D) Panoramic (Pan) tool of Virtual Navigator technology for real-time fusion imaging of breast 3D US volumes with bi-dimensional US scans. A Motion Control Sensor enables the correction of the examined subject's movements. Data about fusion precision and system performances will be presented regarding tests in vitro, in ex-vivo and in vivo.


Assuntos
Mama/anatomia & histologia , Imageamento Tridimensional , Exame Físico , Interface Usuário-Computador , Adulto , Animais , Galinhas , Cor , Feminino , Humanos , Pessoa de Meia-Idade , Imagens de Fantasmas
3.
Artigo em Inglês | MEDLINE | ID: mdl-24109960

RESUMO

Real-time fusion imaging technologies are increasingly being used among interventional radiologists, mostly Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) dataset, fused with Ultrasound (US) imaging. In addition, fusion of Positron Emission Tomography (PET) and CT is increasingly diffused in clinical practice, due to the wide availability of PET scanners and the capability to make either a direct (acquisitions performed within the same system) or an indirect (procedure performed on an external workstation, merging the two different sets of acquired data) fusion with CT data. The present work describes the feasibility of real-time fusion imaging directly between PET data and US imaging, with CT scans being used only for PET-US fusion registration. Data on multimodality registration precision and clinical applications are presented as well.


Assuntos
Fígado/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons/métodos , Interface Usuário-Computador , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Tomografia Computadorizada por Raios X , Ultrassonografia
4.
Artigo em Inglês | MEDLINE | ID: mdl-22254376

RESUMO

The Chronic Cerebro-Spinal Venous Insufficiency, recently described as a possible role in Multiple Sclerosis pathogenesis, is diagnosed and classified with Echo Color Doppler (ECD) examination of the extra- and intra-cranial veins. As to the intracranial examination, the presence of reflux in the deep cerebral veins (DCVs) or in the dural sinuses is inspected, with a new insonation approach, i.e. the transcondylar window. This work describes a procedure for the co-registration of anatomical Proton Density-weighted Magnetic Resonance Images (MRI) with the intracranial ECD obtained through the transcondylar window. The procedure, preliminarily tested on 10 volunteers, allowed to assess what are the DCVs visible from this new insonation approach and their position relative to the surrounding brain tissues.


Assuntos
Angiografia Cerebral/métodos , Veias Cerebrais/anatomia & histologia , Veias Cerebrais/diagnóstico por imagem , Ecoencefalografia/métodos , Aumento da Imagem/métodos , Angiografia por Ressonância Magnética/métodos , Técnica de Subtração , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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