Endogenous skin fluorescence is a good marker for objective evaluation of comedolysis

Objective evaluation of comedone lesions, especially in vivo, remains a cha llenge. We have used the rhino mouse model in combination with topical appl ication of all-trans retinoic acid as a comedolytic agent, to investigate t he potential of fluorescence spectroscopy as a noninvasive technique in the assessment of noninflammatory acne. The results indicate that there is a s trong correlation between the fluorescence excitation spectral features ass essed in vivo, and the histologic changes identified, particularly the size of the utriculi as well as the dermal and epidermal thickness. We conclude that fluorescence excitation spectroscopy represents a promising novel and useful tool in the quantitative evaluation of the pseudocomedones and coul d also be used for the rapid and noninvasive assessment of comedolysis indu ced by the application of pharmacologic agents such as retinoids.