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

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2016

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Tafreshi, Azadeh Kamali

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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.

Subject Keywords

Diagnostic imaging., Doppler ultrasonography., Diagnostic ultrasonic imaging., Breast, Microwave imaging in medicine.

URI

http://etd.lib.metu.edu.tr/upload/12619797/index.pdf
https://hdl.handle.net/11511/25478

Collections

Graduate School of Natural and Applied Sciences, Thesis

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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.