Multifrequency Microwave-Induced Thermal Acoustic Imaging for Breast Cancer Detection

Abstract

Microwave-induced thermal acoustic imaging (TAI) is a promising early breast cancer detection technique, which combines the advantages of microwave stimulation and ultrasound imaging and offers a high imaging contrast, as well as high spatial resolution at the same time. A new multifrequency microwave-induced thermal acoustic imaging scheme for early breast cancer detection is proposed in this paper. Significantly more information about the human breast can be gathered using multiple frequency microwave stimulation. A multifrequency adaptive and robust technique (MART) is presented for image formation. Due to its data-adaptive nature, MART can achieve better resolution and better interference rejection capability than its data-independent counterparts, such as the delay-and-sum method. The effectiveness of this procedure is shown by several numerical examples based on 2-D breast models. The finite-difference time-domain method is used to simulate the electromagnetic field distribution, the absorbed microwave energy density, and the thermal acoustic field in the breast model.

An Integrated Simulation Approach and Experimental Research on Microwave Induced Thermo-Acoustic Tomography System

“…The specific absorption rate (SAR) distributions at 2.45 GHz frequency in breast phantom are obtained. The SAR distribution is used as the initial thermo-acoustic source through the thermal expansion coefficient in the acoustic simulation [2,3].…”

“…Early diagnose is the key to surviving from the breast cancer [2]. Currently, mammography is the most extensively used modality for breast cancer detection.…”

“…However, the 3-D slab-shaped breast model used in [3] is not accord with the real condition. A 2-D breast model is proposed in [2], the frequency band for imaging system was investigated. But other system components, such as antenna and transducers et al were not considered.…”

“…First, the electromagnetic FITD simulation is carried out to obtain the specific absorption rate (SAR) distribution in the breast phantom. Then, the SAR distribution is used as an initial thermo-acoustic pressure source through a conversion by using a thermal expansion coefficient [2]. The thermo-acoustic waves propagate through the coupling medium and the breast tissues to the transducers.…”

Comparison of Radar and Thermoacoustic Technique in Microwave Breast Imaging

“…The linear acoustic attenuation is applicable to the thermoacoustic signals [18]. To capture the dispersion, the quantity "acoustic conductivity" σ a is introduced to form a dual with the electric conductivity and is related to the acoustic attenuation through…”