Terahertz Pulsed Spectroscopy of Human Basal Cell Carcinoma

Abstract

Good contrast is seen between normal tissue and regions of tumor in terahertz pulsed imaging of basal cell carcinoma (BCC). To date, the source of contrast at terahertz frequencies is not well understood. In this paper we present results of a spectroscopy study comparing the terahertz properties (absorption coefficient and refractive index) of excised normal human skin and BCC. Both the absorption coefficient and refractive index were higher for skin that contained BCC. The difference was statistically significant over the range 0.2 to 2.0 THz (6.6 cm(-1) to 66.6 cm(-1)) for absorption coefficient and 0.25 to 0.90 THz (8.3 cm(-1) to 30 cm(-1)) for refractive index. The maximum difference for absorption was at 0.5 THz(16.7 cm(-1)). These changes are consistent with higher water content. These results account for the contrast seen in terahertz images of BCC and explain why parameters relating to the reflected terahertz pulse provide information about the lateral spread of the tumor. Knowing the properties of the tissue over the terahertz frequency range will enable the use of mathematical models to improve understanding of the terahertz response of normal and diseased tissue.

Using a portable terahertz spectrometer to measure the optical properties ofin vivohuman skin

“…In fact, only a few studies have been conducted to characterize the optical properties of in vivo human tissues at THz frequencies. 8,13,14 In addition, previous studies were performed with conventional THz spectrometers, which are not amenable for field applications. In this study, we demonstrate that a portable THz time-domain spectroscopy (TDS) system can be used to accurately measure the optical properties of human skin tissue at THz frequencies.…”

Freeze-thaw hysteresis effects in terahertz imaging of biomedical tissues

“…Several studies have proposed interesting uses of THz waves such as to delineate cancer margins [2][3][4], monitor the water content in living plants [5,6], and detect dental defects [7,8].…”

Analytical and simulation results of micro-ring resonator system using two eyes imaging model

“…Corresponding wavelengths of radiation in this band range are from 1 mm to 0.1 mm (or 100 µm). THz radiation consists of electromagnetic waves with frequency between 0.1 THz to 10 THz, and is widespread biomedical application involving the interaction of terahertz pulse with biological media [31][32][33][34][35][36], where THz radiation has been used successfully as a noninvasive imaging technique for detection of human skin cancer [37,38]. Recently, Yupapin et al have shown the interesting results of whispering gallery mode of light within a PANDA ring circuit [13,14], in which the advantage is that the WGMs can be easily generated and controlled within the PANDA ring circuit, which can be useful for various applications.…”