Long time exposures in autofluorescence imaging of skin lesions– from astrophotography to cancer diagnosis.

Skin cancer accounts for most malignancies across the globe. Non-melanoma skin cancer (NMSC) is the most common type of cancer among Caucasians, however, few data exist on its incidence. Because of a sheer volume of these tumors, NMSC is often not systematically registered. Non-melanoma skin cancer (NMSC) is by far the most common cancer diagnosed in westernized countries, and one of the few almost preventable cancers if detected and treated early as up to 90% of NMSC may be attributed to excessive exposure to ultraviolet radiation. In the study was used a high-sensitivity and resolution camera in the diagnosis of skin lesions, placed on a robotic arm, to obtain long exposures of autofluorescent and fluorescent images. Then, the obtained images were superimposed to obtain a long exposure image that was subjected to digital analysis and color analysis. Due to the use of long image exposures, significantly better contrast parameters were obtained, thereby significantly greater differentiation of healthy and cancerous tissue margins. The obtained images were subjected to digital analysis, obtaining image parameters characteristic for individual types of histopathological skin changes examined. Based on the obtained images, spatial maps of individual image components were obtained, showing the potential for increasing the sensitivity and specificity of skin biopsy lesions. The use of a robotic arm allowed monitoring of the course of photodynamic therapy, which underwent the studied changes, obtaining significantly better results than when using traditional imaging.