title: Measurements of the thermal coefficient of optical attenuation at different depth regions of in vivo human skins using optical coherence tomography: a pilot study.
abstract: We present detailed measurement results of optical attenuation's thermal coefficients (referenced to the temperature of the skin surface) in different depth regions of in vivo human forearm skins using optical coherence tomography (OCT). We first design a temperature control module with an integrated optical probe to precisely control the surface temperature of a section of human skin. We propose a method of using the correlation map to identify regions in the skin having strong correlations with the surface temperature of the skin and find that the attenuation coefficient in these regions closely follows the variation of the surface temperature without any hysteresis. We observe a negative thermal coefficient of attenuation in the epidermis. While in dermis, the slope signs of the thermal coefficient of attenuation are different at different depth regions for a particular subject, however, the depth regions with a positive (or negative) slope are different in different subjects. We further find that the magnitude of the thermal coefficient of attenuation coefficient is greater in epidermis than in dermis. We believe the knowledge of such thermal properties of skins is important for several noninvasive diagnostic applications, such as OCT glucose monitoring, and the method demonstrated in this paper is effective in studying the optical and biological properties in different regions of skin.
authors.affiliation: Tianjin University, Polarization Research Center, College of Precision Instrument & Opto-electronics Engineering and Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Su
authors.affiliation: Tianjin University, Polarization Research Center, College of Precision Instrument & Opto-electronics Engineering and Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China ; General Photonics Corporation, 5228 Edison Avenue, Chino, California 91710, USA.
authors.forename: X Steve
authors.initials: XS
authors.lastname: Yao
authors.affiliation: Tianjin University, Polarization Research Center, College of Precision Instrument & Opto-electronics Engineering and Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China ; Suzhou Opto-ring Co. Ltd., Suzhou 215123, China.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Li
authors.affiliation: Tianjin University, Polarization Research Center, College of Precision Instrument & Opto-electronics Engineering and Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China ; Suzhou Opto-ring Co. Ltd., Suzhou 215123, China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Meng
authors.affiliation: Tianjin University, Polarization Research Center, College of Precision Instrument & Opto-electronics Engineering and Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China.
authors.forename: Tiegen
authors.initials: T
authors.lastname: Liu
authors.affiliation: Tianjin University, Polarization Research Center, College of Precision Instrument & Opto-electronics Engineering and Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China.
authors.forename: Longzhi
authors.initials: L
authors.lastname: Wang
keywords: (170.1470) Blood or tissue constituent monitoring; (170.3660) Light propagation in tissues; (170.4500) Optical coherence tomography