Nummular headache: diagnosis and treatment.

Nummular headache (coin-shaped cephalgia) has an unusual distinct feature: it is characterized by mild-to-moderate pressure-like pain exclusively felt in a rounded or elliptical area typically 2-6 cm in diameter. Although any region of the head may be affected, the parietal area is the common localization of nummular headache. The pain remains confined to the same symptomatic area which does not change in shape or size with time. The pain is continuous but lancinating exacerbations lasting for several seconds or gradually increasing from 10 mins to 2 h may superimpose the baseline pain. The temporal pattern is either chronic or remitting. Pseudoremissions may be observed when the pain reaches a very low grade or only discomfort (not pain) in the affected area is reported. At times, discomfort may prevail. Either during symptomatic periods or interictally, the affected area may show a variable combination of hypoethesia, dysesthesia, paresthesia or tenderness. Physical and supplementary examinations are normal. Nummular headache emerges as a primary clear-cut clinical picture. The particular topography and signs of sensory dysfunction make it reasonable to vent the idea that nummular headache is an extracranial headache, probably stemming from epicranial tissues such as terminal branches of sensitive nerves. Nummular headache may seem to be the paradigm of epicranias (group of headaches and pericranial neuralgias stemming from epicranial tissues). Nummular headache must be distinguished from head pain secondary to local processes and from tender points of more extensive headaches. Although nummular headache may frequently coexist with other primary headaches, it has an independent course. Treatment is seldom necessary and in most cases simple reassurance is sufficient.