Figure 1: (a) Pinhead-sized comedones unilaterally distributed in a zosteriform form on the site of prior herpes zoster. (b) Dermoscopy observation showed numerous barrel-shaped comedonal openings, which were filled with hyperkeratotic plugs and circled with lighter brown halos. (c) Reflectance confocal microscopy observation demonstrated that the infundibulum was enlarged with a bright contour or onion-like appearance