Enhanced optical clearing of human skin at topical application of immersion agents to stratum corneum pretreated by a lattice-like photothermal ablation

摘要

High level of light scattering in mammalian skin significantly deteriorates the effectiveness and precision of light delivery to intra- and subcutaneous targets in therapeutic and diagnostic applications. Optical immersion based on the refractive index matching of tissue scattering centers with surrounding matter via introduction of an exogenous index-matching agent is capable to alleviate the problem. But this process goes slowly enough because of sluggish diffusion of various immersion agents through a stratum corneum (SC) barrier, making a practical realization of this approach difficult. In order to increase the rate of the process we designed the method of accelerating the penetration of optical clearing agents (OCAs) by enhancing skin permeability through a creation of lattice-like pattern of localized thermal damage (ablation) islets in the SC. OCAs, such as glucose, propylene glycol, and glycerol solutions, were applied. Experimental results show a remarkable increase in the rate of optical clearing. The most of results were obtained on in vivo human skin.