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Start Over Topic ultrasonography Publication Year Range Last 10 years
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1. Perfluorooctyl bromide traces self-assembled with polymeric nanovesicles for blood pool ultrasound imaging.

Author

Li H, Wang P, Wang X, Yin T, Zhou G, Shuai X, and Zheng R

Subjects
Animals, Cell Line, Tumor cytology, Contrast Media chemistry, Contrast Media metabolism, Fluorocarbons metabolism, Hydrocarbons, Brominated, Male, Mice, Nanoparticles metabolism, Particle Size, Polyesters chemistry, Polyethylene Glycols chemistry, Polymers chemistry, Polymers metabolism, Rats, Rats, Wistar, Sepharose analysis, Fluorocarbons chemistry, Nanoparticles chemistry, Ultrasonography
Abstract

A novel perfluorooctyl bromide (PFOB)-loaded nanovesicle with a size of about 500 nm was prepared by self-assembly of an amphiphilic block copolymer, poly(ethylene oxide)-b-poly(d,l-lactic acid) (PEG-PDLLA), for blood pool ultrasound imaging. The excellent compatibility of PFOB with the hydrophobic PDLLA block makes PFOB uniformly distribute and integrate well within the nanovesicle shell. In theory, both the compressibility and shell density of the nanovesicle as ultrasound scatterers are enhanced, resulting in much higher echo intensity compared to the other PFOB nanoparticles. In vitro and in vivo imaging results illustrate that these polymeric nanovesicles with extremely low content of PFOB show quite a good contrast-enhancing effect even if highly diluted in blood. Therefore this PFOB-loaded polymeric nanovesicle is anticipated to be applicable as an ultrasound contrast agent for normal angiography and specific imaging of capillary-abundant organs or tissues (e.g. tumors).

Published
2016
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2. Three-dimensional Simulation of Quantitative Ultrasound in Cancellous Bone using the Echographic Response of a Metallic Pin

Author

Yoshiki Nagatani, Salah Naili, Vu-Hieu Nguyen, Séraphin Guipieri, Guillaume Haїat, Christine Chappard, Didier Geiger, Department of Electronics [Kobe, Japan], Kobe City College of Technology [Kobe, Japan], Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Laboratoire de Modélisation et Simulation Multi Echelle (MSME), Université Paris-Est Marne-la-Vallée (UPEM)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Bioingénierie et Bioimagerie Ostéo-articulaires, Biomécanique et Biomatériaux Ostéo-Articulaires (B2OA (UMR_7052)), École nationale vétérinaire - Alfort (ENVA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), This study was supported in part by KAKENHI (Grant Number 25871038 and 16K01431) from the Japan Society for the Promotion of Science (JSPS) and the PRTS program (project OsseoWave n°ANR-13-PRTS-0015-02) of French National Research Agency (ANR). This paper has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement No 682001, project ERC Consolidator Grant 2015 BoneImplant)., Haiat, Guillaume, Institut National de la Santé et de la Recherche Médicale (INSERM)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-IFR10, Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-École nationale vétérinaire d'Alfort (ENVA), and Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Paris-Est Marne-la-Vallée (UPEM)

Subjects
FDTD Simulation, Materials science, Swine, FOS: Physical sciences, 3d model, Reflector (antenna), Physics - Classical Physics, Bone Nails, 01 natural sciences, 030218 nuclear medicine & medical imaging, 03 medical and health sciences, 0302 clinical medicine, Spine surgery, Imaging, Three-Dimensional, 0103 physical sciences, medicine, Animals, Radiology, Nuclear Medicine and imaging, Femur, 010301 acoustics, Ultrasonography, Discopathy, Radiological and Ultrasound Technology, 3D Model, Soft tissue, Classical Physics (physics.class-ph), Physics - Medical Physics, [PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph], Vertebral body, Quantitative ultrasound, Three dimensional simulation, medicine.anatomical_structure, Metals, Models, Animal, Cancellous Bone, Medical Physics (physics.med-ph), Quantitative ultrasound (QUS), [PHYS.MECA.ACOU] Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph], Cancellous bone, Biomedical engineering
Abstract

Degenerative discopathy is a common pathology that may require spine surgery. A metallic cylindrical pin is inserted into the vertebral body to maintain soft tissues and may be used as a reflector of ultrasonic wave to estimate bone density. The first aim of this paper is to validate a three-dimensional (3-D) model to simulate the ultrasonic propagation in a trabecular bone sample in which a metallic pin has been inserted. We also aim at determining the effect of changes of bone volume fraction (BV/TV) and of positioning errors on the quantitative ultrasound (QUS) parameters in this specific configuration. The approach consists in coupling finite-difference time-domain simulation with X-ray microcomputed tomography. The correlation coefficient between experimental and simulated speed of sound (SOS)—respectively, broadband ultrasonic attenuation (BUA)—was equal to 0.90 (respectively, 0.55). The results show a significant correlation of SOS with BV/TV ( R = 0.82), while BUA values exhibit a nonlinear behavior versus BV/TV. The orientation of the pin should be controlled with an accuracy of around 1° to obtain accurate results. The results indicate that using the ultrasonic wave reflected by a pin has a potential to estimate the bone density. SOS is more reliable than BUA due to its lower sensitivity to the tilt angle.

Published
2017