12 May 1995 Optical fiber-based spectrophotometer for in-vivo monitoring of indocyanine green concentration
Author Affiliations +
We have developed a two-wavelength spectrophotometer for in vivo monitoring of indocyanine green (ICG) concentration. Light from two laser diodes, one with output at 788 nm (near the optical absorption peak of ICG) and the other with output at 905 nm (where the optical absorption of ICG is essentially zero), is coupled into small-diameter multimode optical fibers which transport the light to the tissue under investigation. A third optical fiber collects the reflected and remitted light and transports it to a photodetector. The fibers can either be placed on the surface of the tissue or implanted using a hypodermic needle. By analyzing the intensity of the reflected light from the two light sources, we can accurately predict the concentration of ICG present over a wide range of scattering coefficients of the tissue. We have characterized the performance of the spectrophotometer using tissue phantoms composed of suspensions of IntralipidTM as a scatterer (0.1 - 3.0%), with ICG concentrations ranging from 100 nM to 20 (mu) M.
© (1995) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Travis W. Evans, Travis W. Evans, Kenneth Eugene Bartels, Kenneth Eugene Bartels, Steven A. Schafer, Steven A. Schafer, } "Optical fiber-based spectrophotometer for in-vivo monitoring of indocyanine green concentration", Proc. SPIE 2395, Lasers in Surgery: Advanced Characterization, Therapeutics, and Systems V, (12 May 1995); doi: 10.1117/12.209068; https://doi.org/10.1117/12.209068

Back to Top