title: Review of short-wave infrared spectroscopy and imaging methods for biological tissue characterization.
abstract: We present a review of short-wave infrared (SWIR, defined here as ∼1000 to 2000 nm) spectroscopy and imaging techniques for biological tissue optical property characterization. Studies indicate notable SWIR absorption features of tissue constituents including water (near 1150, 1450, and 1900 nm), lipids (near 1040, 1200, 1400, and 1700 nm), and collagen (near 1200 and 1500 nm) that are much more prominent than corresponding features observed in the visible and near-infrared (VIS-NIR, defined here as ∼400 to 1000 nm). Furthermore, the wavelength dependence of the scattering coefficient has been observed to follow a power-law decay from the VIS-NIR to the SWIR region. Thus, the magnitude of tissue scattering is lower at SWIR wavelengths than that observed at VIS or NIR wavelengths, potentially enabling increased penetration depth of incident light at SWIR wavelengths that are not highly absorbed by the aforementioned chromophores. These aspects of SWIR suggest that the tissue spectroscopy and imaging in this range of wavelengths have the potential to provide enhanced sensitivity (relative to VIS-NIR measurements) to chromophores such as water and lipids, thereby helping to characterize changes in the concentrations of these chromophores due to conditions such as atherosclerotic plaque, breast cancer, and burns.
authors: University of California, Irvine, Beckman Laser Institute, 1002 Health Sciences Road, Irvine, California 92612, United States.
authors: Robert H
authors: RH
authors: Wilson
authors: University of California, Irvine, Beckman Laser Institute, 1002 Health Sciences Road, Irvine, California 92612, United States.
authors: Kyle P
authors: KP
authors: Nadeau
authors: Raytheon Vision Systems, 75 Coromar Drive, Goleta, California 93117, United Sates.
authors: Frank B
authors: FB
authors: Jaworski
authors: University of California, Irvine, Beckman Laser Institute, 1002 Health Sciences Road, Irvine, California 92612, United States.
authors: Bruce J
authors: BJ
authors: Tromberg
authors: University of California, Irvine, Beckman Laser Institute, 1002 Health Sciences Road, Irvine, California 92612, United States.
authors: Anthony J
authors: AJ
authors: Durkin
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging; D001834:Body Water / Q000000981:diagnostic imaging; D001943:Breast Neoplasms / Q000000981:diagnostic imaging; D002056:Burns / Q000000981:diagnostic imaging; D003094:Collagen; D003952:Diagnostic Imaging; D005260:Female; D006801:Humans; D061848:Optical Imaging / Q000379:methods*; D058226:Plaque, Atherosclerotic; D012542:Scattering, Radiation; D013055:Spectrophotometry, Infrared; D019265:Spectroscopy, Near-Infrared
chemical_list: D003094:Collagen