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High Intensity Focused Ultrasound as a non-invasive treatment method has gaining its popularity in various clinical application. HIFU is usually used with navigation system with which to make pre-operative plan. Our group developed a US-guided HIFU system for breast cancer treatment. In order to precisely remove the tumor region and reduce the damage to the surrounding normal tissue to minimal level,...
Aim of this work was to evaluate the effectiveness of a recently introduced ultrasound (US) method for osteoporosis diagnosis, when extensively used in a clinical context to investigate adult women of variable age. A total of 384 female patients (46–65 years; body mass index < 25 kg/m2) underwent a spinal dual X-ray absorptiometry (DXA) and an abdominal US scan of lumbar spine, acquiring both echographic...
There exist a wide variety of time sensitive contexts (e.g. image-guided neurosurgery (IGNS)), whereby image registration is required to be both fast and accurate if it is to be adopted clinically. Many sampling techniques have been proposed to speed up the registration process but these often come at the expense of accuracy (e.g. random). In this paper, we describe a fast and accurate multi-modal...
Indoor localization based on time difference of arrival (TDOA) has been recently a promising field of study. We consider the previously unsolved problem of locating a moving target receiver by using unsynchronized stationary beacons without requirement of manual calibration. Thus, the received signals and their time of arrival (TOA) have to be assigned to a beacon. Besides, in order to automatically...
Multi-dimensional ultrasound displacement estimation accuracy can be improved by projecting high resolution radio frequency (RF) based axial (along the beam) displacements estimated at multiple beam steering angles. When the beam steering angle increases or when the ratio between ultrasound frequency and element pitch becomes larger, grating lobe artifacts increase, which distorts the displacement...
We present a novel and fast interactive approach to multi-modality cardiac image segmentation, which employs the linearly ordered surfaces as an additional constraint. We show using such a geometrical constraint helps to significantly reduce user interaction and improve the accuracy of segmentation results at the same time. We solve the proposed multiregion segmentation problem with the order constraints...
Localization techniques for indoor environments are constantly evolving. In this paper, an approach that combines two different techniques is presented. In detail, the passive thermal infrared localization system (ThILo) is used in combination with the ultrasound and RF based localization system Cricket. In contrast to other indoor localization systems, ThILo exploits the natural thermal radiation...
The endocardium tracking in ultrasound images is challenging due to large shape variations and the signal dropout. In this paper, we present a method to fuse multiple information sources to robustly track the endocardium. The first novelty of the method is to perform tracking in a straightened shape space, to minimize the image pattern changes caused by cardiac motions. Straightened images are used...
This study assessed the utility of machine learning for isolating noise and artifacts in breast ultrasound images. Such corrupt image regions (ROIs) can be automatically excluded when registering images acquired from different angles. Artifacts included posterior acoustic shadowing and enhancement arising from cancers and cysts respectively. Images were obtained on a breast-mimicking phantom containing...
In this paper we evaluate the innate ability of mobile phone speakers to produce ultrasound and the possible uses of this ability for accurate indoor positioning. The frequencies in question are a range between 20 and 22 KHz, which is high enough to be inaudible but low enough to be generated by standard sound hardware. A range of tones is generated at different volume settings on several popular...
Whole heart segmentation of 3D ultrasound (US), also referred to as echocardiography or simply echo, is useful in cardiac functional analysis to achieve quantitative diagnostic information of the heart. However, characteristics of US imaging such as limited field-of-view, artifacts and inconsistent intensity distribution makes automated approaches a challenge. In this paper, we present a framework...
In this paper, we present our work using ultrasonic sensing of speech for digit recognition. First, a set of spectral ultrasonic features are developed and tuned in order to achieve optimal performance for the digit recognition task. Using these features, we demonstrate an overall accuracy of 33.00% on a digit recognition task using HMMs with recordings from 6 speakers. The results indicate that ultrasonic...
Flying four-rotor robots (quadrocopters) are on-board sensor controlled systems. In comparison to classical monorotor objects (helicopters), quadrocopters can be piloted with a much lower effort. However, lateral drifts can not be compensated only referring to the built-in sensors. The detection of such drifts is strongly necessary for indoor operation - without corrections a quadrocopter would quickly...
The device intended for measurement of depth of hole is described, the block diagram of the device is depicted, as well as the new method of processing echo-signals is offered and analyzed to reduce measurement error.
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