Indocyanine green (ICG) enhances penetration of 1300 nm optical coherence tomography imaging for <i>in vivo</i> murine skin.

Optical scattering in biological tissues presents a major challenge for achieving deep penetration in optical coherence tomography (OCT). Recent approaches leveraging the Kramers-Kronig (KK) relations suggest that strongly absorbing dyes can reduce scattering by modulating the tissue's refractive index. In this study, we investigate the use of indocyanine green (ICG), an FDA clinically approved near-infrared dye, as an optical clearing agent (OCA) for 1300 nm OCT imaging. Due to its strong absorption near 780 nm and its binding affinity to plasma proteins and lipids, ICG presents a promising candidate for KK-based optical clearing in fatty tissues. We validated ICG's clearing potential using 1300 nm OCT on the abdominal skin of a non-pigmented mouse for in vivo imaging. Our findings indicate that ICG enhances imaging contrast and increases penetration depth, demonstrating its potential for non-invasive, contrast-enhanced 1300-OCT imaging. These findings could benefit dermatological applications of OCT by enhancing image quality to reveal greater detail in the skin.

Duke Scholars

Author David Miller  

Author Adam P. Wax Biomedical Engineering

Author Junjie Yao Biomedical Engineering