Enhancement of OCT imaging by blood optical clearing in vessels – A feasibility study

Abstract Objective: The results of a feasibility study of the application of PEG-300 and fructose as two independent optical clearing agents for the reduction of light scattering in biological tissues are presented. Materials and methods: An OCT system operating at 1300 nm was used to study optical clearing effects. In in-vitro experiments in mice (n=2) an increase of the imaging depth was observed after intravenous injection of PEG-300 alone and in combination with intradermal injection of fructose. The optical clearing effect was also studied for the first time in two mice in vivo using intravenous injection of PEG-300 or solution of hemoglobin. Results: The intradermal injection of fructose in combination with the intravenous injection of PEG-300 led to a rapid optical clearing effect. In the experiments on mice in vivo the injection of PEG-300 or hemoglobin solution into the tail vein of the living mice allowed for a rapid enhancement of the vein wall and the surrounding tissue image contrast. Conclusion: The experiments on mice have clearly demonstrated that intradermal and intravenous injections of optical clearing agents enhanced light transport through the skin and blood vessels.