Infinity hair: a new trichoscopic finding for chemotherapy‐induced alopecia

Funding sources: none. Conflicts of interest: The authors declare they have no conflicts of interest. Dear Editor, We retrospectively analysed the trichoscopic images of patients with nonscarring (n = 112) and scarring (n = 30) alopecia. We detected exclusively in three out of 12 cases of chemotherapy‐induced alopecia a trichoscopic feature we termed ‘infinity hair’ (IH). At trichoscopic assessment, the patients had stopped chemotherapy for 5–9 months. IH is a regrowing hair with a tapered end that takes the form of the mathematical sign for ‘infinity’ (Figure 1a, b). This differs from circle hairs, which have the same calibre along the hair shaft (Figure 1c), and pigtail hairs, which taper towards the tip (Figure 1d).1 2 IH may represent a variant of pigtail hair.