Title :
Evaluation of Contrast Enhancement by Carbon Nanotubes for Microwave-Induced Thermoacoustic Tomography
Author :
Jian Song ; Zhiqin Zhao ; Jinguo Wang ; Xiaozhang Zhu ; Jiangniu Wu ; Zaiping Nie ; Qing-Huo Liu
Author_Institution :
Sch. of Electron. Eng., Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
Microwave-induced thermoacoustic tomography (MITAT) is a hybrid method which constructs images with ultrasound spatial resolution while exploiting dielectric contrast at microwave frequency. It has great potential in biomedical imaging especially in early breast cancer detection. The detection of early stage breast tumor in MITAT is challenged by the moderate endogenous dielectric contrast between malignant and healthy glandular tissues. In order to overcome this limitation, the performance of using carbon nanotubes (CNTs) as an imaging contrast enhancement agent is evaluated. First, the influences in dielectric and acoustic properties caused by CNTs are measured. Second, based on the measurements and the published data, numerical breast phantom is created and then used to explore the contrast enhancing effect of CNTs for MITAT, by an integrated simulation approach in both electromagnetic and acoustic field. With an experimental MITAT system, the thermoacoustic responses of tissue mimicking materials with different CNTs concentrations are also quantitatively investigated. Finally, the effectiveness of the contrast agent is also validated experimentally by using a MITAT system. The results show that the using of the dielectric contrast agent can effectively enhance the contrast of the MITAT image.
Keywords :
acoustic tomography; bioelectric phenomena; biological effects of microwaves; biomimetics; biothermics; cancer; carbon nanotubes; image enhancement; image resolution; mammography; nanomedicine; numerical analysis; permittivity; phantoms; physiological models; thermoacoustics; tumours; C; CNT concentration; CNT contrast enhancing effect; MITAT image construction; MITAT image contrast enhancement; acoustic field; acoustic properties; biomedical imaging; carbon nanotube; contrast agent effectiveness validation; contrast enhancement evaluation; dielectric properties; early breast cancer detection; early stage breast tumor detection; electromagnetic field; experimental MITAT system; experimental validation; healthy glandular tissue; imaging contrast enhancement agent; integrated simulation; malignant glandular tissue; microwave frequency; microwave-induced thermoacoustic tomography; moderate endogenous dielectric contrast; numerical breast phantom; quantitative thermoacoustic response investigation; tissue mimicking material response; ultrasound spatial resolution; Acoustics; Breast; Conductivity; Dielectrics; Microwave imaging; Tumors; Breast tumor detection; Thermo-acoustic imaging; breast tumor detection; carbon nanotubes; contrast agent; thermoacoustic imaging;
Journal_Title :
Biomedical Engineering, IEEE Transactions on
DOI :
10.1109/TBME.2014.2373397