Ultrasound enhanced synthetic platelet therapy for augmented wound repair.

Native platelets perform a number of functions within the wound healing process, including interacting with fibrin fibers at the wound site to bring about retraction after clot formation. Clot retraction improves clot stability and enhances the function of the fibrin network as a provisional matrix to support cellular infiltration of the wound site, thus facilitating tissue repair and remodeling after hemostasis. In cases of traumatic injury or disease, platelets can become depleted and this process disrupted.

In Vivo Assessment of Pulmonary Fibrosis and Pulmonary Edema in Rodents Using Ultrasound Multiple Scattering.

Idiopathic pulmonary fibrosis (IPF) affects 200 000 patients in the United States of America. IPF is responsible for changes in the micro-architecture of the lung parenchyma, such as thickening of the alveolar walls, which reduces compliance and elasticity. In this study, we verify the hypothesis that changes in the microarchitecture of the lung parenchyma can be characterized by exploiting multiple scattering of ultrasound waves by the alveolar structure.

Lesion Imaging and Target Detection in Multiple Scattering (LITMUS) Media.

We present an ultrasound algorithm [lesion imaging and target detection in multiple scattering (LITMUS)] suited to image lesions (hypoechoic) or targets (hyperechoic) in highly complex structures. In such media, standard ultrasound imaging techniques fail to detect lesions or targets due to aberrations and the loss of linearity between propagation distance and propagation time, caused by multiple scattering of ultrasound waves. The present algorithm (LITMUS) has the capability to predict the location as well as the size of such lesions/targets by using the multiple scattered ultrasound signals to its advantage.

Artificial neural network to estimate micro-architectural properties of cortical bone using ultrasonic attenuation: A 2-D numerical study.

The goal of this study is to estimate micro-architectural parameters of cortical porosity such as pore diameter (φ), pore density (ρ) and porosity (ν) of cortical bone from ultrasound frequency dependent attenuation using an artificial neural network (ANN). First, heterogeneous structures with controlled pore diameters and pore densities (mono-disperse) were generated, to mimic simplified structure of cortical bone. Then, more realistic structures were obtained from high resolution CT scans of human cortical bone.

Predicting Structural Properties of Cortical Bone by Combining Ultrasonic Attenuation and an Artificial Neural Network (ANN): 2-D FDTD Study.

The goal of this paper is to predict the micro-architectural parameters of cortical bone such as pore diameter and porosity from ultrasound attenuation measurements using an artificial neural network (ANN). Slices from a 3-D CT scan of human femur are obtained. The micro-architectural parameters of porosity such as average pore size and porosity are calculated using image processing.

Ultrasound multiple scattering with microbubbles can differentiate between tumor and healthy tissue in vivo.

Most solid tumors are characterized by highly dense, isotropic vessel networks. Characterization of such features has shown promise for early cancer diagnosis. Ultrasound diffusion has been used to characterize the micro-architecture of complex media, such as bone and the lungs.

Observation of Self-Bending and Focused Ultrasound Beams in the Megahertz Range.

Self-bending (or self-accelerating) and nondiffracting acoustic beams, such as Airy beams, have the potential to focus around obstacles that are directly in the beam path. Here, we demonstrate the self-bending and focusing properties of Airy beams in the ultrasound domain using finite difference time-domain simulations at 5.2 MHz.

Microstructural characterization of trabecular bone using ultrasonic backscattering and diffusion parameters.

Finite differences time domain methods were utilized to simulate ultrasound propagation and scattering in anisotropic trabecular bone structures obtained from high resolution Computed Tomography (CT). The backscattered signals were collected and the incoherent contribution was extracted. The diffusion constant was calculated for propagations along and across the main direction of anisotropy, and was used to characterize the anisotropy of the trabecular microstructures.

Characterization of the Lung Parenchyma Using Ultrasound Multiple Scattering.

The purpose of the study described here was to showcase the application of ultrasound to quantitative characterization of the micro-architecture of the lung parenchyma to predict the extent of pulmonary edema. The lung parenchyma is a highly complex and diffusive medium for which ultrasound techniques have remained qualitative. The approach presented here is based on ultrasound multiple scattering and exploits the complexity of ultrasound propagation in the lung structure.