(Synonym: Atrophy of the Hair.)

What do you understand by atrophy of the hair?

An atrophic, brittle, dry condition of the hair, and which may be either symptomatic or idiopathic.

Describe the several conditions met with.

As a symptomatic affection, the dry, brittle condition of the hair met with in seborrhoea, in severe constitutional diseases, and in the various vegetable parasitic affections, may be referred to.

As an idiopathic disease it is rare, consisting simply of a brittleness and an uneven and irregular formation of the hair-shaft, with a tendency to split up into filaments (fragilitas crinium); or there may be localized swelling and bursting of the hair-shaft, the nodes thus produced having a shining, semi-transparent appearance (trichorrhexis nodosa). This latter usually occurs upon the beard and moustache.

State the causes of atrophy of the hair.

The causes of the symptomatic variety are usually evident; the etiology of idiopathic atrophy is obscure, but by many is thought due to parasitism.

Fig. 39.

Trichorrhexis Nodosa. (After Michelson.)

What would be your prognosis and treatment in atrophy of the hair?

Symptomatic atrophy usually responds to proper measures, but always slowly; treatment is based upon the etiological factors.

For the idiopathic disease little, as a rule, can be done; repeated shaving or cutting the hair has, in exceptional instances, been followed by favorable results.