Optical microscopy and XRF maps, spatial distribution of Ti. (a) Patient 5, optical microscopy showing red ink (higher magnification HES ×400, arrowheads) in the mid-dermis, at the periphery of a diffused inflammatory infiltrate (HES ×40, arrows: lower limits of the inflammatory infiltrate). (b) Patient 5, XRF map, showing Ti on the periphery of the inflammatory infiltrate (arrows: lower limits of the inflammatory infiltrate). (c) Patient 6. In these two samples, Ti is co-located with the pigment. (d) Patient 2, Ti is located around a hair follicle bulb.