SWIR Fluorescence and Monte Carlo Modeling of Tissues for Medical Applications

Iida, Tatsuto, Taiyo Yuden Co. Ltd.; Kiya, Shunsuke, Maebashi Institute of Technology; Kubota, Kosuke, Maebashi Institute of Technology; Seiyama, Akitoshi, Kyoto Univ. Graduate School & Faculty of Medicine; Jin, Takashi, RIKEN; Nomura, Yasutomo, Maebashi Institute of Technology

doi:10.1117/3.2604326.ch7

Book: Short-Wavelength Infrared Windows for Biomedical Applications

Editor(s): Laura A. Sordillo; Peter P. Sordillo

Chapter Author(s): Tatsuto Iida, Shunsuke Kiya, Kosuke Kubota, Akitoshi Seiyama, Takashi Jin, Yasutomo Nomura

Published: 2021

https://doi.org/10.1117/3.2604326.ch7

Author Affiliations +

Abstract

Electromagnetic waves at various bandwidths—such as gamma rays (at ~2 x 10^–3 nm, for positron emission tomography), X-rays (at ~10^–2 nm, for mammograms), and visible light (VIS) (at ~520 nm, for fluorescein angiography)—have been utilized for medical diagnosis. Recently, bioprobes that emit light in the short-wavelength infrared (SWIR, 1000–2500 nm) have emerged as novel optical tools in the assessment of disease. SWIR-emitting fluorescent probes, such as quantum dots and other nanoparticle-based materials (e.g., single-walled carbon nanotubes, rare-earth-doped nanoparticles, carbon nanoparticles, and silicon-based nanostructures), have been investigated. Several research groups are now developing biocompatible SWIRemitting organic probes with little toxicity. At select wavelengths in the SWIR wavelength range, scattering and absorption of light in tissues is reduced compared to other wavelengths. Therefore, compared to conventional VIS and near-infrared (NIR) fluorescence imaging, SWIR fluorescence imaging may provide deeper-tissue images with high spatial resolution. To understand the advantages of SWIR fluorescence imaging, it is important to examine the features of fluorescence tissue imaging in the VIS, NIR, and SWIR wavelength ranges.