[Focal neuropathy].

The differential diagnosis of focal neuropathy continues to be one of the main tasks in peripheral neurology and clinical neurophysiology. In this respect a detailed medical history a topologically oriented clinical examination based on profound anatomical knowledge and a targeted neurophysiological examination are the cornerstones of successful diagnosis. Refined imaging techniques, such as sonography and magnetic resonance imaging provide - additional and valuable morphological information especially in atypical or unresolved cases. The aim of this overview is therefore to summarize the spectrum of focal neuropathy and diagnostic approaches, particularly in terms of a well-founded differential diagnosis.