PHP applications, K-wave simulations and experimental studies for medical ultrasound

Download

index.pdf

Date

2017

Author

Kulga, Utku Baran

Metadata

Show full item record

Item Usage Stats

362
views

528
downloads

This study has three parts related to theoretical calculations, numerical simulations and experimental studies in the field of medical ultrasound. The goal of the first part is to prepare computer codes for the education of biomedical engineering students. For this purpose, a series of computer applications is prepared using the hypertext preprocessor (PHP) programming language. Accessing the associated internet address, the students will be able to learn the basics of ultrasound using the interactive, visual, cost-effective infrastructure of the developed computer applications. Snell’s Law, Reflection and Transmission Characteristics of Ultrasound, Attenuation Phenomenon, Pressure Wave, Power Intensity Concepts, Doppler Effect, Piezoelectric Materials, Near and Far Field Calculations, Transducer Design, A-Mode and B-Mode Ultrasound, Effects of Frequency and Tissue Types can be studied by means of these applications. The second part includes simulation studies made for the calculation of ultrasound waves in biological tissues. In these simulations, an open source acoustic toolbox for MATLAB (k-Wave) is used. The accuracy and speed in solutions are assessed using simple sources and body geometries. The third part is on the experimental studies. Experiments are conducted using an ultrasound system that employs a 16-channel phased array ultrasound transducer. Ultrasound phantoms are developed and used to acquire pulse-echo signals. The same geometry and acoustic properties of the phantom are used to acquire one-dimensional pulse echo signals in the PHP application and in the K-Wave simulations. The similarities and differences in the signals obtained from the PHP application, K-Wave simulation, and experimental studies are discussed. Keywords:

Subject Keywords

Ultrasonics in medicine., Diagnostic ultrasonic imaging.

URI

http://etd.lib.metu.edu.tr/upload/12620876/index.pdf
https://hdl.handle.net/11511/26339

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Representation of human brain by mesh networks Önal Ertuğrul, Itır; Yarman Vural, Fatoş Tunay; Department of Computer Engineering (2017) In this thesis, we propose novel representations to extract discriminative information in functional Magnetic Resonance Imaging (fMRI) data for cognitive state and gender classification. First, we model the local relationship among a set of fMRI time series within a neighborhood by considering temporal information obtained from all measurements in time series. The estimated local relationships, called Mesh Arc Descriptors (MADs), are employed to represent information in fMRI data. Second, we adapt encoding ...
2D simulations based on the general time dependent reciprocal relation and initial experiments for LFEIT / Karadaş, Mürsel; Gençer, Nevzat Güneri; Department of Electrical and Electronics Engineering (2014) In this study, the new imaging modality Lorentz Field Electrical Impedance Tomography (LFEIT) is investigated. In LFEIT, the main aim is finding the conductivity distribution of different tissues. This method is based on the development of the current density distribution in the conductive medium. To develop the current density, the object is located in a static magnetic field and pressure wave due to an ultrasonic transducer develops particle movements inside the body. As a result, a velocity current distr...
A medical image processing and analysis framework Çevik, Alper; Eyüboğlu, Behçet Murat; Oğuz, Kader Karlı; Department of Biomedical Engineering (2011) Medical image analysis is one of the most critical studies in field of medicine, since results gained by the analysis guide radiologists for diagnosis, treatment planning, and verification of administered treatment. Therefore, accuracy in analysis of medical images is at least as important as accuracy in data acquisition processes. Medical images require sequential application of several image post-processing techniques in order to be used for quantification and analysis of intended features. Main objective...
Bridging Brain and Educational Sciences: An Optical Brain Imaging Study of Visuospatial Reasoning Çakır, Murat Perit; Izzetoglu, Meltem; Shewokis, Patricia A.; Izzetoglu, Kurtulus; Onaral, Banu (2011-10-22) In this paper we present an experimental study where we investigated neural correlates of visuospatial reasoning during math problem solving in a computer-based environment to exemplify the potential for conducting interdisciplinary research that incorporates insights from educational research and cognitive neuroscience. Functional near-infrared spectroscopy (fNIRS) technology is used to measure changes in blood oxygenation in the dorsolateral and inferior prefrontal cortex while subjects attempt to solve t...
Theoretical investigation of effects of flow oscillations on ultrasound Doppler velocity measurements Koseli, Volkan; Uludağ, Yusuf (Elsevier BV, 2012-02-01) Effects of flow oscillations on spectrum of Ultrasound Doppler Velocimetry (UDV) signals were investigated theoretically and numerically. A laminar pipe flow with a superimposed oscillating component was considered. Negative impact of oscillation on the ultrasound signal hence on the flow images was observed in the form of spreading of spectral ultrasound signal energy around mean component, leading to image artifacts. Both analytical and numerical results revealed the strong effect of a group of parameters...

Citation Formats

U. B. Kulga, “PHP applications, K-wave simulations and experimental studies for medical ultrasound,” M.S. - Master of Science, Middle East Technical University, 2017.