Design and realization of a hybrid medical imaging system: harmonic motion microwave doppler imaging

Tafreshi, Azadeh Kamali
Harmonic Motion Microwave Doppler Imaging (HMMDI) is a novel imaging modality to image electrical and mechanical properties of body tissues. This modality is recently proposed by the researchers in the METU EEE department for early-stage diagnosis of cancerous tissues. The main goal of this thesis study is to contribute various stages of the HMMDI's development processes. Speci cally, phantom development, dielectric and elastic characterization of the phantoms, experimental system realization, phantom experiments, and system performance evaluation, are in the scope of this thesis study. In the earlier stages, di effrent phantoms that mimic the mechanical and electrical properties of the body tissues are developed and characterized. In parallel to the phantom studies, experimental system design and realization studies are performed and the performance of the designed system is tested using phantom materials. The developed phantoms are scanned using the HMMDI method and the extracted information is used to generate HMMDI data profi les of the phantoms. The potential of detecting different tissues phantoms from the generated data pro files is explored. Eff ect of different vibration frequencies in HMMDI is discussed. In the acquired 2-D HMMDI data profi les, the potential of this imaging method in detecting 1) 5 mm tumor inside the fat, 2) 14 mm tumor phantom inside 25 mm fibro-glandular phantom in the middle of the fat phantom, 14 mm fi bro-glandular phantom inside the fat phantom, and 14 mm tumor inside the fat phantom, at the depth of 20 mm depths are observed. The experimental system limitations are clarif ed and the possible solutions to improve the system are presented.


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© 2020 EurAAP.Harmonic motion microwave Doppler imaging is a novel imaging modality that combines focused ultrasound and radar techniques to obtain data based on mechanical and electrical properties of the tissue. In previous experimental studies, the Doppler component of the scattered signal is sensed and used to create 2D images of a tumor inside a homogeneous fat phantom. Due to the drawbacks of the receiver configuration, scanning time was high, the signal-to-noise ratio was low, and the multi-frequency...
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Received Signal in Harmonic Motion Microwave Doppler Imaging as a Function of Tumor Position in a 3D Scheme
IRGIN, Umit; TOP, Can Baris; TAFRESHI, Azadeh Kamali; Gençer, Nevzat Güneri (2017-02-08)
Harmonic Motion Microwave Doppler Imaging method, which was proposed as an alternative method for breast tumor detection, is a combination of microwave radar and focused ultrasound techniques yielding data depending on electrical and mechanical properties of the tissue. In this study, Harmonic Motion Microwave Doppler Imaging data from a small tumor inside homogeneous fat is analyzed as a function of tumor location on three orthogonal planes using Finite Difference Time Domain simulations. The results show ...
Citation Formats
A. K. Tafreshi, “Design and realization of a hybrid medical imaging system: harmonic motion microwave doppler imaging,” Ph.D. - Doctoral Program, Middle East Technical University, 2016.