Harmonic motion microwave doppler imaging method

Top, Can Barış
Conventional method for breast tumor detection, mammography, has a number of drawbacks such as X-ray exposure, patient discomfort and loss of reliability especially for dense breast tissue. Therefore, it is a hot research topic to develop new alternative non-invasive, reliable, safe and patient friendly breast imaging methods. In this thesis, we propose a novel hybrid mechanical and electromagnetic imaging method to identify cancerous regions particularly inside dense glandular breast tissue at the early stage by making use of the contrast between elastic and electrical properties of healthy and malignant tissues. A small vibrating region is created inside the tissue using the radiation force of focused ultrasound waves. A microwave transceiver is used to collect data from the vibrating region at the Doppler frequency, which depends on both elastic and electrical properties. The vibrating region is scanned inside the tissue to generate images. A semi-analytical formulation for the forward problem is developed using a two-layered simple breast model. A three dimensional Finite Difference Time Domain (FDTD) method is developed for analyzing the scattered signal from a vibrating region inside the tissue. Forward multi-physics problem is solved numerically with successive acoustic, mechanical and electromagnetic simulations. The performance of the method is investigated using both homogeneous and realistic numerical tissue models. Phantom materials that mimic the electrical and elastic properties of the fatty, fibro-glandular and malignant breast tissues are developed. The proof of concept is demonstrated experimentally on breast phantom materials using general measurement devices. A 5 mm diameter tumor phantom inside fibro-glandular tissue phantom was identified at 25 mm depth. Simulation results show that even smaller tumors can be detected inside breast issue if specialized receivers and transmitters are used. Even though the performance of the method is investigated for breast tumor detection in the scope of this thesis, it can be used for detecting tumors in the other organs that are microwave and ultrasound penetrable.


Three dimensional finite difference time domain simulations on harmonic motion microwave doppler imaging method using realistic tissue models
Tatar, Fikret; Gençer, Nevzat Güneri; Department of Electrical and Electronics Engineering (2019)
Imaging of electromagnetic and elastic properties of the breast tissue can be used to identify cancerous regions in the dense fibro glandular breast tissue at the early stage. Numerical simulations are useful in predicting the performance of the imaging method. In Harmonic Motion Microwave Doppler Imaging Method (HMMDI), tissue is vibrated locally, microwave signals illuminate the tissue and the back scattered Doppler signal component is used to form images. In this thesis, forward problem of HMMDI method i...
Data Acquisition System for Harmonic Motion Microwave Doppler Imaging
Tafreshi, Azadeh Kamali; Karadas, Muersel; Top, Can Baris; Gençer, Nevzat Güneri (2014-08-30)
Harmonic Motion Microwave Doppler Imaging (HMMDI) is a hybrid method proposed for breast tumor detection, which images the coupled dielectric and elastic properties of the tissue. In this paper, the performance of a data acquisition system for HMMDI method is evaluated on breast phantom materials. A breast fat phantom including fibro-glandular and tumor phantom regions is produced. The phantom is excited using a focused ultrasound probe and a microwave transmitter. The received microwave signal level is mea...
Implementation of a fast simulation tool for the analysis of contrast mechanisms in HMMDI and enhancement of the SNR in the experimental set-up
İrgin, Ümit; Gençer, Nevzat Güneri; Top, Can Barış; Department of Electrical and Electronics Engineering (2021-9-06)
Clinical method for breast tumor detection is Mammography (X-rays), which have limitations and may yield inaccurate results. Alternative novel techniques are required to characterize the breast tissues and extract accurate information for identification of malignancies in the tissue. Harmonic Motion Microwave Doppler Imaging (HMMDI), which enhances hybridizing microwave signals and ultrasound techniques, has been recently proposed for detection of tumors in the tissue. In HMMDI method, the data is a combina...
Magnetohydrodynamic flow imaging of ionic solutions using electrical current injection and MR phase measurements
Eroglu, Hasan H.; Sadighi, Mehdi; Eyüboğlu, Behçet Murat (Elsevier BV, 2019-06-01)
In this study, a method is proposed to image magnetohydrodynamic (MHD) flow of ionic solutions, which is caused by externally injected electrical current to an imaging media, during MRI scans. A multi-physics (MP) model is created by using the electrical current, laminar flow, and MR equations. The conventional spoiled gradient echo MRI pulse sequence with bipolar flow encoding gradients is utilized to encode the MHD flow. Using the MP model and the MRI pulse sequence, relationship between the MHD flow rela...
Harmonic Motion Microwave Doppler Imaging method for breast tumor detection
Top, Can Baris; Tafreshi, Azadeh Kamali; Gençer, Nevzat Güneri (2014-08-30)
Harmonic Motion Microwave Doppler Imaging (HMMDI) method is recently proposed as a non-invasive hybrid breast imaging technique for tumor detection. The acquired data depend on acoustic, elastic and electromagnetic properties of the tissue. The potential of the method is analyzed with simulation studies and phantom experiments. In this paper, the results of these studies are summarized. It is shown that HMMDI method has a potential to detect malignancies inside fibro-glandular tissue.
Citation Formats
C. B. Top, “Harmonic motion microwave doppler imaging method,” Ph.D. - Doctoral Program, Middle East Technical University, 2013.