[Differential diagnostic studies using the dermatoscope in selected diseases].

The Zeis dermatoscope can be used beyond its known applications for precise and detailed skin surface examinations of different types of dermatosis. Differential diagnostic problems are solved by comparative observation of efflorescence and efflorescence fields of similar appearance. The examination series presented, the results of which are discussed in detail, is concerned mainly with surface examinations of parapsoriasis en plaques, seborrhea en plaques and the clinically similar early forms of mycosis fungoides. Also mentioned are examinations of lichen sclerosus et atrophicus and circumscribed scleroderma, lichen planus, Hutchinson-Dubreuilh freckle and similarly appearing facial verruca seborrhoica, as well as fresh dispersions of foreign bodies. The didactic value is underlined by color photographs taken of diseased skin and nails with the dermatoscope at various magnifications. Finally, a description is given of possible instrument extensions.