Dermoscopy of non-skin cancer nail disorders.

Nail dermoscopy is becoming more and more frequently utilized for the diagnosis of nail disorders. It can be performed with handy dermoscope or with a video dermoscope, which allows magnifications of up to 200. Nail dermoscopy requires a good knowledge of nail anatomy and physiology and the pathogenesis of nail diseases: we have to know which part of the nail we have to look at! The nail is in fact not visible as a whole at one time, but its different parts should be observed, moving the lens back and forth and transversally. All nail disorders can be observed by dermoscopy. However, except for some diseases in which the technique really adds a lot to clinical examination, in most of the cases, nail dermoscopy only permits a better visualization of symptoms already evident to the naked eye. Dermoscopic features of nail signs are always very interesting and surprising, and may help in our understanding of nails.