Leveraging the Imaging Transmit Pulse to Manipulate Phase-Change Nanodroplets for Contrast-Enhanced Ultrasound.
IEEE Trans Ultrason Ferroelectr Freq Control
; 66(4): 692-700, 2019 04.
Article
em En
| MEDLINE
| ID: mdl-30703017
ABSTRACT
Phase-change perfluorohexane nanodroplets (PFHnDs) are a new class of recondensable submicrometer-sized contrast agents that have potential for contrast-enhanced and super-resolution ultrasound imaging with an ability to reach extravascular targets. The PFHnDs can be optically triggered to undergo vaporization, resulting in spatially stationary, temporally transient microbubbles. The vaporized PFHnDs are hyperechoic in ultrasound imaging for several to hundreds of milliseconds before recondensing to their native, hypoechoic, liquid nanodroplet state. The decay of echogenicity, i.e., the dynamic behavior of the ultrasound signal from optically triggered PFHnDs in ultrasound imaging, can be captured using high-frame-rate ultrasound imaging. We explore the possibility to manipulate the echogenicity dynamics of optically triggered PFHnDs in ultrasound imaging by changing the phase of the ultrasound imaging pulse. Specifically, the ultrasound imaging system was programmed to transmit two imaging pulses with inverse polarities. We show that the imaging pulse phase can affect the amplitude and the temporal behavior of PFHnD echogenicity in ultrasound imaging. The results of this study demonstrate that the ultrasound echogenicity is significantly increased (about 78% improvement) and the hyperechoic timespan of optically triggered PFHnDs is significantly longer (about four times) if the nanodroplets are imaged by an ultrasound pulse starting with rarefactional pressure versus a pulse starting with compressional pressure. Our finding has direct and significant implications for contrast-enhanced ultrasound imaging of droplets in applications such as super-resolution imaging and molecular imaging where detection of individual or low-concentration PFHnDs is required.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Processamento de Imagem Assistida por Computador
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Ultrassonografia
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Nanopartículas
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Fluorocarbonos
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
IEEE Trans Ultrason Ferroelectr Freq Control
Assunto da revista:
MEDICINA NUCLEAR
Ano de publicação:
2019
Tipo de documento:
Article
País de publicação:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA