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The main purpose of this paper is to develop a theoretical tool in order to fundamentally characterize the performance of Myocardial elastography and identify the optimal parameters to be used for the more reliable detection of ischemia or infarction. A complete representation of the left-ventricular function throughout an entire cardiac cycle was previously demonstrated through the use of a 3D finite-element...
Tissue stiffness is generally known to be associated with pathologic changes. Ultrasound indentation is able to assess the mechanical properties of soft tissues. Conventional ultrasound indentation devices use rigid flat-ended transducers to directly contact with the tissues and typically operate in the frequency ranging between 2 M Hz and 10 MHz. This paper introduced a novel ultrasound indentation...
We investigated the B-mode ultrasound (US) images of abdomen by normalizing the gray level values of the liver with the representative gray levels (RGL's) of the liver parenchyma, renal cortex, subcutaneous fat, to quantify the fatty infiltration of the liver (FIL). The RGL's were compared with the clinical diagnosis of the FIL showing good correlation between them
A high frequency contrast-assisted destruction/reperfusion imaging system has been developed to improve image resolution in previous study. Our goal in this work is to build a fast and robust algorithm to evaluate volumetric microcirculation blood flow. The microcirculation flow rate is determined by the multiplication of perfusion area and corresponding blood flow velocity mapping. The blood flow...
The anterior cruciate ligament (ACL) functions as a mechanical stabilizer in the tibiofemoral joint. Over 250,000 Americans each year suffer ACL ruptures and tears, making the ACL the most commonly injured knee ligament. Methods which permit the in situ monitoring of changes in ACL graft mechanical properties during healing are needed. A long term goal in ACL reconstruction is to regenerate the ACL-bone...
Image registration has been widely used for generating more diagnostic and clinical values in medical imaging. On the other hand, inaccurate image registration and incorrect localization of region of interest risks a potential impact on patients. Vibro-acoustography (VA) is a new imaging modality that has been applied to both medical and industrial imaging. Combining unique diagnostic information...
In the diagnosis and therapy of prostate cancer, it is critical to measure the volume of the prostate and locate its boundary. Three-dimensional transrectal ultrasound (3D TRUS) imaging has been demonstrated to be a useful technique to perform such a task. Due to image speckle as well as low contrast in ultrasound images, segmentation of the prostate in 3D US images is challenging. In this paper,...
Non-invasive cardiovascular measurements are used to evaluate cardiovascular diseases early and to cure early. By using various evaluation methods of cardiovascular features to diagnose cardiovascular disease. Flow-mediated dilation (FMD) evaluated by ultrasound offers a mechanism to characterize endothelial function and, therefore, may play a role in the diagnosis of cardiovascular diseases. Cardiovascular...
Automatic contouring for breast tumors using medical ultrasound (US) imaging may assist physicians, without relevant experience, in making correct diagnoses. This study utilizes the watershed transform and active contour model (ACM) to overcome the natural properties of US images, speckle, noise and tissue-related textures, to segment the breast tumors precisely. The watershed transform is performed...
To cure brain paralysis this paper has briefly summarized the rudimentary knowledge of the ultrasonic therapy, and briefly introduced the methods of dolphin ultrasonic therapy, through the research of the dolphin ultrasonic therapy, the ultrasonic frequency chart wave band which is more efficient to the therapy of brain paralysis is measured, and one method of simulated dolphin therapy mechanism is...
This paper describes a system for dynamic intraoperative prostate brachytherapy using 3D ultrasound guidance with robotic assistance. The system consists of 3D TRUS imaging, a robot and software for prostate segmentation, intraoperative planning, oblique needle segmentation and tracking, seed segmentation, and 3D dose planning. The robot and 3D TRUS coordinate systems are unified through robot and...
A new method to accurately measure the mechanical properties of individual muscles and tendons under active contraction is presented. An individual muscle is activated selectively to different intensities through electrical stimulation with adjustable amplitude, frequency, and pulse width. During the course of active contraction of the stimulated muscle, muscle fiber pennation angle, muscle fascicle...
Wave propagation through the arterial system changes with age and disease state, and mutant mice are often used to study these conditions. We have developed several noninvasive ultrasonic techniques to measure blood velocity and vessel wall motion from which we can calculate aortic pulse wave velocity (PWV), local compliance, impedance spectra, characteristic impedance (Zc), augmentation index (AI),...
Molecular techniques are transforming our understanding of cellular function and disease. However, accurate molecular analysis methods will be limited if the input DNA, RNA, or protein is not derived from pure population of cells or is contaminated by the wrong cells. Ultrasonic vibration microdissection provides the technology to procure pure population of targeted cells from tissue sections for...
Color flow imaging plays a major role in the diagnosis of many vascular diseases, especially cardiovascular disease. The imaging quality is highly influenced by the clutter originating from the vascular wall, stationary and slowly moving tissues and relative motion between the probe held by doctor and the blood flow. The clutter rejection filter in front of the mean frequency estimator will restrict...
Optical coherence tomography (OCT) is a new technique mainly used in biomedical imaging. Here we present a particle-fixed Monte Carlo (PFMC) simulation for OCT. The scattering particles of the sample are assumed to be temporarily fixed randomly in the simulation process of backscattering light. The new model explains the exponential decay signal at the interface of different media layers in OCT experimental...
Image segmentation is a fundamental image process technique and plays an essential role in ultrasound image analysis. In this article, we propose an algorithm for image segmentation which is based on the random neural network (RNN) and features extracted by a bank of Gabor filters. With the scientists' work, it is revealed that Gabor functions act as some functions of human vision. And the RNN model...
Brachytherapy is a minimally invasive interventional surgery used to treat prostate cancer. It is composed of three steps: dose pre-planning, implantation of radioactive seeds, and dose post-planning. In these procedures, it is crucial to determine the positions of needles and seeds, measure the volume of the prostate gland. Three-dimensional transrectal ultrasound (TRUS) imaging has been demonstrated...
We propose a local weak form formulation for the geometric deformable model (GDM) which is capable of achieving robust segmentation results for noisy and broken edges. The local weak form partial differential equation (PDE) is solved on the analysis/evolution domain which is adaptively sampled by unstructured point cloud for improved accuracy and/or reduced computational cost. The fundamental power...
High intensity focused ultrasound (HIFU) is one of promising non invasive thermal ablation techniques of tumor, and the demand of imaging for guidance the HIFU procedure is becoming important. We choose ultrasound imaging method based on sequence images to locate the focal position of the HIFU. To the characteristic of ultrasound sequence images, we adopt a diffusion stick method for speckle noise...
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