JAMES M.GRICHNIKMD, PhDASHFAQ A.MARGHOOBMDALONSCOPEMD
Dermoscopy aids in distinguishing ashy dermatosis and hyperpigmented lichen planus (LP) lesions that tend to persist for a longer period.1Figure 1A shows a violaceous papule and regressing brown macules on the forearm of a 67-year-old woman with LP. Dermoscopy of the former reveals Wickham striae (WS) surrounded by capillaries (Figure 1B). Regressing lesions reveal a structureless brown pigmentation in the absence of granularity (Figure 1C, arrows). Such a pattern favors a transient clinical course, as demonstrated in Figure 1D, which shows the disappearance of pigmentation in less than 1 year.
Vázquez-López F, Vidal AM, Zalaudek I. Dermoscopic Subpatterns of Ashy Dermatosis Related to Lichen Planus. Arch Dermatol. 2010;146(1):110. doi:10.1001/archdermatol.2009.300