Rosettes and other white shiny structures in polarized dermoscopy : histological correlate and optical explanation
Journal of the European Academy of Dermatology and Venereology. - Amsterdam
, p. 311-313
University of Antwerp
BackgroundRosettes are a specific form of a white shiny structure seen with polarized dermoscopy. The precise morphological correlate and optical explication are not known. ObjectiveTo estimate the frequency of rosettes in exvivo dermoscopy and to find explication and morphologic correlate of this dermoscopic feature. MethodsA series of 6108 consecutive skin biopsies were examined with exvivo dermoscopy and when rosettes were present serial transverse sections with polarization were examined. ResultsIn this series of 6108 consecutive skin biopsies, rosettes were found on exvivo dermoscopy in 63 cases. When multiple we observed that they are always oriented at the same angle. Transverse sections with polarization of these lesions proved that smaller rosettes are mainly caused by polarizing horny material in adnexal openings, and larger rosettes by concentric perifollicular fibrosis. ConclusionsRosettes are an optical effect of crossed polarization by concentric fibrosis or horny material and hence are not lesion-specific.