In vivo enhancement of imaging depth for optical coherence tomography by eudermic agents on ridged and meshed human skin

Non-invasive skin analysis by optical coherence tomography (OCT) is limited because of the absorption and scattering properties of the tissue. There are several possibilities for enhancing OCT images. The purpose of this study was to demonstrate that image quality can be improved using the hyperosmolar agents glucose and glycerol while investigating human ridged and meshed skin areas, without causing damage to the tissue. The experiments were carried out on the palm and the forearm of ten volunteers. After application of the substances in the test area, the penetration depth and image contrast were measured at intervals of 5 min for a total duration of 60 min. Both agents clearly improved the OCT imaging depth in comparison to untreated human skin. The results demonstrated that glucose had a faster diffusion rate than glycerol. Consequently, it can be concluded that the treatment with glucose or glycerol for optical clearing of the skin tissue results in an improved image quality if applied 15–25 min prior to clinical testing. (letter)