Definition And Description

This is an usually elevated mark, more or leas thickly covered with hair, and frequently accompanied with increased pigment deposit. The color may vary from a shade hardly darker than the normal skin to a hue approaching that of the negro. The hair3 may likewise be little more than downy and colorless, or they may acquire an appreciable thickness and color. These naevi are found on every part of the body, exist in any number, and vary in size.

Treatment

The appearance of these naevi would, of course, be improved by the destruction of the hairs. The various depilatories are not to be relied on, as their action is very superficial, and their effect but temporary, the hairs soon growing again, and sometimes more vigorously than before. It is necessary to destroy the hair papillae, and as this is located quite deep in the skin, especially in the case of the larger hairs, we would be obliged to destroy nearly, if not quite, the whole thickness of the skin. This can, of course, be effected with caustics, but then is apt to leave unsightly scars. In a few instances I have improved the appearance of the naevi by destroying the hair-follicles and papillae by an electrolytic process first published by me five years ago+ (87, 307).

Fig. 22. - Needle-holder for electrolyzing hair-follicles.

The implements required are an epilation forceps, a very fine steel needle, a needle-holder (Fig. 22), and a galvanic battery. A hair is removed with the forceps, and the needle connected with the negative pole of the battery, inserted into the empty follicle. The galvanic circuit is then closed, and in about half a minute the follicle will be destroyed. The operation requires patience, practice, and sharp eyes, assisted sometimes with a lens. It is only the larger hairs that it is practicable to deal with in this way.

* They sometimes undergo malignant degeneration.

+ Unknown to me at the time, Michel, of St. Louis. had employed electrolysis for the destruction of distorted hairs connected with the eyelids.

Small and favorably situated hairy naevi may sometimes be excised; if very prominent they may be shaved off down to the level of the skin.