JAMES M.GRICHNIKMD, PhDASHFAQ A.MARGHOOBMDALONSCOPEMD
Certain dermoscopic structures are more conspicuous with nonpolarized dermoscopy (NPD), while others are more conspicuous with polarized dermoscopy (PD).1,2 The introduction of “hybrid” dermoscopes allows the user to toggle between polarized and nonpolarized light. We found that structures that are more conspicuous with either NPD or PD appear to “blink” when the observer toggles between light modes. Figure 1 is a melanoma. With PD (Figure 1B), shiny white lines, or crystalline structures (formerly called chrysalislike structures) are visible.3 Because they are not visible with NPD (Figure 1A), they appear to blink when the observer toggles between NPD and PD (Video 1). Figure 2 is a seborrheic keratosis. With NPD (Figure 2A), multiple comedo openings and milia cysts are seen. Because milia cysts and comedo openings are less conspicuous with PD (Figure 2B), they blink when the observer toggles between light sources (Video 2).
Braun RP, Scope A, Marghoob AA. The “Blink Sign” in Dermoscopy. Arch Dermatol. 2011;147(4):520. doi:10.1001/archdermatol.2011.82" videolink="1