scholarly journals Quantitative Interpretation of UWB Radar Images for Non-Invasive Tissue Temperature Estimation during Hyperthermia

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 818
Author(s):  
Alexandra Prokhorova ◽  
Sebastian Ley ◽  
Marko Helbig
Keyword(s):  
Three Dimensional ◽  
Microwave Frequency ◽  
Ultra Wideband ◽  
Tissue Temperature ◽  
Hyperthermia Treatment ◽  
Temperature Estimation ◽  
Radar Images ◽  
Non Invasive ◽  
Uwb Radar ◽  
Thermal Therapies

The knowledge of temperature distribution inside the tissue to be treated is essential for patient safety, workflow and clinical outcomes of thermal therapies. Microwave imaging represents a promising approach for non-invasive tissue temperature monitoring during hyperthermia treatment. In the present paper, a methodology for quantitative non-invasive tissue temperature estimation based on ultra-wideband (UWB) radar imaging in the microwave frequency range is described. The capabilities of the proposed method are demonstrated by experiments with liquid phantoms and three-dimensional (3D) Delay-and-Sum beamforming algorithms. The results of our investigation show that the methodology can be applied for detection and estimation of the temperature induced dielectric properties change.

scholarly journals Ultra-Wideband Temperature Dependent Dielectric Spectroscopy of Porcine Tissue and Blood in the Microwave Frequency Range

Sensors ◽  
2019 ◽  
Vol 19 (7) ◽  
pp. 1707 ◽  
Author(s):  
Sebastian Ley ◽  
Susanne Schilling ◽  
Ondrej Fiser ◽  
Jan Vrba ◽  
Jürgen Sachs ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Microwave Frequency ◽  
Ultra Wideband ◽  
Frequency Range ◽  
Temperature Dependent ◽  
Hyperthermia Treatment ◽  
Non Invasive ◽  
Animal Liver ◽  
Cole Model ◽  
Diagnostic Technologies

The knowledge of frequency and temperature dependent dielectric properties of tissue is essential to develop ultra-wideband diagnostic technologies, such as a non-invasive temperature monitoring system during hyperthermia treatment. To this end, we characterized the dielectric properties of animal liver, muscle, fat and blood in the microwave frequency range from 0.5 GHz to 7 GHz and in the temperature range between 30 °C and 50 °C. The measured data were modeled to a two-pole Cole-Cole model and a second-order polynomial was introduced to fit the Cole-Cole parameters as a function of temperature. The parametric model provides access to the dielectric properties of tissue at any frequency and temperature in the specified range.

The Effects of Large Blood Vessels on Three-Dimensional Tissue Temperature Distributions During Electromagnetic Induced Nano-Hyperthermia: Numerical Simulation

2008 ◽  
Author(s):  
Zhong-Shan Deng ◽  
Jing Liu
Keyword(s):  
Blood Vessels ◽  
Tumor Cells ◽  
Three Dimensional ◽  
The Body ◽  
Thermal Therapy ◽  
Tissue Temperature ◽  
Surrounding Tissue ◽  
Temperature Profiles ◽  
Hyperthermia Treatment ◽  
Tumor Hyperthermia

As is well known, the blood flowing through large blood vessels acts as a heat sink and plays an important role in affecting temperature profiles of heated tissues [1]. In hyperthermia, heating is usually limited to the tumor and a small margin of the surrounding tissue. Since the temperatures in the rest of the body remain normal, the blood that supplies the tumor will be relatively cold. Consequently, the blood flow inside a large vessel will represent a sink which cools the nearby heated tissues and then limits heating lesion during tumor hyperthermia. Under this adverse condition, a part of vital tumor cells may remain in the thermally lethal area and lead to recurrence of tumors after hyperthermia treatment. More specifically, tumor cell survival in the vicinity of large blood vessels is often correlated with tumor recurrence after thermal therapy. Therefore, it is difficult to implement an effective hyperthermia treatment when a tumor is contiguous to a large blood vessel or such vessel transits the tumor. How to totally destroy tumor cells in the vicinity of large blood vessels has been a major challenge in hyperthermia [2].

scholarly journals UWB Transmission through Human Thorax: An Index of Cardiac Health

2020 ◽  
Vol 16 (13) ◽  
pp. 70
Author(s):  
Kedar Nath Sahu ◽  
Challa Dhanunjaya Naidu ◽  
Jaya Sankar Kottareddygari
Keyword(s):  
Power Transmission ◽  
Periodic Variation ◽  
Propagation Model ◽  
Ultra Wideband ◽  
Cardiac Health ◽  
Transmission Coefficients ◽  
Non Invasive ◽  
Uwb Radar ◽  
Human Thorax ◽  
Invasive Measurement

There are many applications which require remote and non-invasive measurement of heartbeat of a human being using an ultra-wideband (UWB) radar. Sophisticated models and their analysis need to be referred before the design of a practical radar prototype. In this paper, i) a UWB wave propagation model of human thorax and ii) the power transmission coefficients estimated from the simulations of the model in the range 1-10 GHz using MATLAB are presented. The study reveals that there is a periodic variation of the transmission coefficients in correlation with the instantaneous physical dimensions of an active heart.

Preliminary Investigations of Microwave Imaging Algorithms for Tissue Temperature Estimation During Hyperthermia Treatment

2021 ◽  
Author(s):  
Alexandra Prokhorova ◽  
Sebastian Ley ◽  
Alvaro Yago Ruiz ◽  
Rosa Scapaticci ◽  
Lorenzo Crocco ◽  
...  
Keyword(s):  
Microwave Imaging ◽  
Tissue Temperature ◽  
Hyperthermia Treatment ◽  
Temperature Estimation ◽  
Imaging Algorithms

scholarly journals Through-Wall Multi-Subject Localization and Vital Signs Monitoring Using UWB MIMO Imaging Radar

2021 ◽  
Vol 13 (15) ◽  
pp. 2905
Author(s):  
Zhi Li ◽  
Tian Jin ◽  
Yongpeng Dai ◽  
Yongkun Song
Keyword(s):  
Continuous Wave ◽  
Multiple Input Multiple Output ◽  
Three Dimensional ◽  
Vital Signs ◽  
Low Frequency ◽  
Mimo Radar ◽  
Ultra Wideband ◽  
Radar Images ◽  
Imaging Radar ◽  
Vital Signs Monitoring

Radar-based non-contact vital signs monitoring has great value in through-wall detection applications. This paper presents the theoretical and experimental study of through-wall respiration and heartbeat pattern extraction from multiple subjects. To detect the vital signs of multiple subjects, we employ a low-frequency ultra-wideband (UWB) multiple-input multiple-output (MIMO) imaging radar and derive the relationship between radar images and vibrations caused by human cardiopulmonary movements. The derivation indicates that MIMO radar imaging with the stepped-frequency continuous-wave (SFCW) improves the signal-to-noise ratio (SNR) critically by the factor of radar channel number times frequency number compared with continuous-wave (CW) Doppler radars. We also apply the three-dimensional (3-D) higher-order cumulant (HOC) to locate multiple subjects and extract the phase sequence of the radar images as the vital signs signal. To monitor the cardiopulmonary activities, we further exploit the VMD algorithm with a proposed grouping criterion to adaptively separate the respiration and heartbeat patterns. A series of experiments have validated the localization and detection of multiple subjects behind a wall. The VMD algorithm is suitable for separating the weaker heartbeat pattern from the stronger respiration pattern by the grouping criterion. Moreover, the continuous monitoring of heart rate (HR) by the MIMO radar in real scenarios shows a strong consistency with the reference electrocardiogram (ECG).

scholarly journals Non-Invasive Driver Drowsiness Detection System

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4833
Author(s):  
Hafeez Ur Rehman Siddiqui ◽  
Adil Ali Saleem ◽  
Robert Brown ◽  
Bahattin Bademci ◽  
Ernesto Lee ◽  
...  
Keyword(s):  
Support Vector Machine ◽  
Detection System ◽  
Ultra Wideband ◽  
Gradient Boosting ◽  
Support Vector ◽  
Drowsiness Detection ◽  
Non Invasive ◽  
Driver Drowsiness ◽  
Uwb Radar ◽  
Tree Classifier

Drowsiness when in command of a vehicle leads to a decline in cognitive performance that affects driver behavior, potentially causing accidents. Drowsiness-related road accidents lead to severe trauma, economic consequences, impact on others, physical injury and/or even death. Real-time and accurate driver drowsiness detection and warnings systems are necessary schemes to reduce tiredness-related driving accident rates. The research presented here aims at the classification of drowsy and non-drowsy driver states based on respiration rate detection by non-invasive, non-touch, impulsive radio ultra-wideband (IR-UWB) radar. Chest movements of 40 subjects were acquired for 5 m using a lab-placed IR-UWB radar system, and respiration per minute was extracted from the resulting signals. A structured dataset was obtained comprising respiration per minute, age and label (drowsy/non-drowsy). Different machine learning models, namely, Support Vector Machine, Decision Tree, Logistic regression, Gradient Boosting Machine, Extra Tree Classifier and Multilayer Perceptron were trained on the dataset, amongst which the Support Vector Machine shows the best accuracy of 87%. This research provides a ground truth for verification and assessment of UWB to be used effectively for driver drowsiness detection based on respiration.

X-ray microtomography

1988 ◽  
Vol 46 ◽  
pp. 998-999
Author(s):  
H.W. Deckman ◽  
B.F. Flannery ◽  
J.H. Dunsmuir ◽  
K.D' Amico
Keyword(s):  
Computed Tomography ◽  
Internal Structure ◽  
Imaging Technique ◽  
Three Dimensional ◽  
Tissue Structure ◽  
Individual Element ◽  
X Ray ◽  
Non Invasive ◽  
Panoramic Imaging ◽  
Three Dimensional Images

We have developed a new X-ray microscope which produces complete three dimensional images of samples. The microscope operates by performing X-ray tomography with unprecedented resolution. Tomography is a non-invasive imaging technique that creates maps of the internal structure of samples from measurement of the attenuation of penetrating radiation. As conventionally practiced in medical Computed Tomography (CT), radiologists produce maps of bone and tissue structure in several planar sections that reveal features with 1mm resolution and 1% contrast. Microtomography extends the capability of CT in several ways. First, the resolution which approaches one micron, is one thousand times higher than that of the medical CT. Second, our approach acquires and analyses the data in a panoramic imaging format that directly produces three-dimensional maps in a series of contiguous stacked planes. Typical maps available today consist of three hundred planar sections each containing 512x512 pixels. Finally, and perhaps of most import scientifically, microtomography using a synchrotron X-ray source, allows us to generate maps of individual element.

Three-dimensional speckle-tracking echocardiography – a further step in the non-invasive three-dimensional cardiac imaging

2012 ◽  
Vol 153 (40) ◽  
pp. 1570-1577 ◽  
Author(s):  
Attila Nemes ◽  
Anita Kalapos ◽  
Péter Domsik ◽  
Tamás Forster
Keyword(s):  
Cardiac Imaging ◽  
Speckle Tracking ◽  
Speckle Tracking Echocardiography ◽  
Three Dimensional ◽  
Myocardial Mechanics ◽  
Non Invasive ◽  
Imaging Methodology ◽  
Invasive Evaluation

Three-dimensional speckle-tracking echocardiography is a new cardiac imaging methodology, which allows three-dimensional non-invasive evaluation of the myocardial mechanics. The aim of this review is to present this new tool emphasizing its diagnostic potentials and demonstrating its limitations, as well. Orv. Hetil., 2012, 153, 1570–1577.

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