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Regular video cameras shoot normally at 25/30 frames per second (fps). Actually there are available in the market equipments that allow us to acquire video at 1.000.000 fps. When we observe a video sequence it becomes noticeable that great part of the information remains unchanged regardless of the bit rate or frame rate used. One origin of discontinuity in video signals is directly related to movement...
Digital Image Elasto Tomography (DIET) is a non-invasive elastographic breast cancer screening technology, based on image-based measurement of surface vibrations induced on a breast by mechanical actuation. Knowledge of frequency response characteristics of a breast prior to imaging is critical to maximize the imaging signal and diagnostic capability of the system. A feasibility analysis for a non-invasive...
This paper summarizes dynamic measurements of shear modulus constants acquired for spontaneously growing rat mammary tumors. Measurements are compared with histology to determine tumor types. We also report on 3D shear-wave velocity fields acquired from an inhomogeneous hydrogel phantom with known mechanical properties. Phantom measurements enable us to interpret the effects of tissue structure and...
This paper presents a phase-based method for estimating subpixel motion in medical ultrasound imaging. The main novelty is to propose a closed form expression for local motion estimation in space domain based on the model of the monogenic signal. First, the proposed method uses the properties of the monogenic signal in order to extract local orientation and phase data of ultrasound images. Second,...
The early detection of biomechanical modifications in the arterial wall could be used as a predictor factor for various diseases, for example hypertension or atherosclerosis. In this work a transient elastography technique is used for the in vitro evaluation of the arterial wall elasticity. The obtained Young modulus is compared with the one obtained by a more classical approach: pressure-diameter...
An important goal in clinical cardiology is the non-invasive quantification of regional cardiac deformation. While many methods have been proposed for the estimation of 3D left ventricular deformation and strains derived from 4D ultrasound, currently there is a lack of in vivo clinical validation of these algorithms on humans. In this paper, we describe the experiments used in validating cardiac deformation...
Our group has been investigating the use of Shearwave Dispersion Ultrasound Vibrometry (SDUV) for quantifying viscoelasticity of the myocardium. The primary aim of this study is the design and testing of viscoelastic materials suitable for validation of the Lamb wave model in the heart. The Lamb wave SDUV method was used to measure shear wave velocity dispersion of gelatin and urethane rubber plates...
We present an approach to wearable sensor-based assessment of motor function in individuals post stroke. We make use of one on-body inertial measurement unit (IMU) to automate the functional ability (FA) scoring of the Wolf Motor Function Test (WMFT). WMFT is an assessment instrument used to determine the functional motor capabilities of individuals post stroke. It is comprised of 17 tasks, 15 of...
Current methods for assessing the efficacy of treatments for Parkinson's disease (PD) rely on physician rated scores. These methods pose three major shortcomings: 1) the subjectivity of the assessments, 2) the lack of precision on the rating scale (6 discrete levels), and 3) the inability to assess symptoms except under very specific conditions and/or for very specific tasks. To address these shortcomings,...
In this paper we show how healthy subjects can operate a non-invasive asynchronous BCI for controlling a FES neuroprosthesis and manipulate objects to carry out daily tasks in ecological conditions. Both, experienced and novel subjects proved to be able to deliver mental commands with high accuracy and speed. Our neuroprosthetic approach relies on a natural interaction paradigm, where subjects delivers...
Combining non-invasive monitoring of action-related brain signals with the invasive recordings of the nerve motor output could provide robust natural and bidirectional multimodal Brain-Machine interfaces. One 26 years old, right-handed male who had suffered traumatic trans-radial amputation of the left arm was connected in a bidirectional way with a robotic hand prostheses. Cortical signals related...
The kinematics of hand movement have been reported to be encoded in neural activities recorded at the primary motor cortex accompanying or immediately preceding the movement. In our earlier study, we demonstrated that the speed of imagined hand movements can be represented in the noninvasive EEG recordings and continuously decoded. In the present work, we aimed to systematically examine the spectral-temporal...
To patients who have lost the functionality of their hands as a result of a severe spinal cord injury or brain stroke, the development of new techniques for grasping is indispensable for reintegration and independency in daily life. Functional Electrical Stimulation (FES) of residual muscles can reproduce the most dominant grasping tasks and can be initialized by brain signals. However, due to the...
Surface mechanomyograms (S-MMGs) are recorded from low frequency (<;100 Hz) mechanical oscillations that are naturally generated by skeletal muscle during voluntary contractions. This study investigates a method to determine the propagation directionality of the S-MMG waves. A 3 × 5 grid of skin mounted accelerometers was mounted on the biceps brachii muscle during submaximal voluntary contractions...
The acoustic radiation force has been used as the method to examine the physical properties of materials in several areas. Vibro-acoustography is an acoustic radiation force technique that is being used to perform analysis of mechanical properties of materials. In this application a focused acoustic modulated force excites target which vibrates at the frequency of modulation. The emitted sound is...
A 170μW readout IC for a capacitive MEMS acceleration sensor was implemented in a 1.5V 0.13μm CMOS for high-end medical motion sensing applications. The accelerometer achieves a 45μg/vHz noise floor and a dynamic range larger than 87dB for a 400Hz bandwidth. Power reduction is achieved by introducing reset and common-mode feedback circuit techniques based on a non-unity-gain feedback configuration.
Current work is a part of long term research, which aim is to study the possibilities to diagnose the atherosclerosis in early stadium by using pulse wave velocity and its waveform analysis. The mobile experimental measurement complex is built and technically tested for the long term study in hospital. Measurement complex consists of ten physiological signal recording channels and reference devices:...
Model and simulation of biological systems help to better understand these systems. In ICUs patients often reach a complex situation where supportive maneuvers require special expertise. Among them, mechanical ventilation in patients suffering from acuter respiratory distress syndrome (ARDS) is specially challenging. This work presents a model which can be simulated and use to help in training of...
We present a reduced order finite element (FE) algorithm suitable for real-time nonlinear simulation of soft tissues. A dynamic FE formulation with explicit time integration is employed. We demonstrate significant computation acceleration by performing the time integration in a low-dimensional generalised basis, generated from a set of a priori training simulations. The key mechanism for the acceleration...
This paper describes the basic guidelines for developing an innovative biomedical device. It covers the issues of researching about a suitable material, developing a new device, and testing its proprieties to check its effectiveness. The goal of the device is to control food flow into the esophagus, reducing its volume and the speed of food intake to help in the treatment of obesity. This module,...
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