Transmission and scanning electron microscopy of cutis rhomboidalis.

Cutis rhomboidalis nuchae was assessed in a 65-year-old patient. Optical microscopy showed basophilic agglomerations in the reticular dermis with decreased elastic fibers. Transmission electron microscopy showed elongated, curved and fragmented structures, and in their interior the presence of electron-dense lumps was reduced and irregular, similar to modified elastic fibers, whereas the collagen fibers had a normal aspect. Scanning electron microscopy showed deposits between the bundles of collagen, resembling pebbles or stones. These findings demonstrate that, at one stage of the disease, the collagen remains normal and the alterations are seen in the elastic tissue.