N.EVI A tilevus is a congenital new formation: that is, an affection which was either present at birth or developed later from a congenital dis position. According to their origin Neisser distinguishes between the true tissue nievi in whieh the neoplasm has originated by the prolifera tion of one particular portion of the tissue: and the organic tnevi which the neoplasm has been produced hy the proliferation of certain organic parts of the skin. In nearly all tissue inevi there is more or less pronounced accumulation of pigment.
The simplest form of nrevi are the ephelides (freckles), yellowish to dark brown spots, smooth and round or angular, from pinhead to lentil size, which appear on the exposed parts of the body, especially in the face and on the hands. Ephelides occur principally in summer, very often in spring when the sun shines somewhat strongly; and pale off in autumn and winter. Usually they do not occur before the fifth or sixth year, and frequently disappear spontaneously in later years.
In contradistinction to these growths the true soft nievi are to be described as prominent formations which by an increase of tissue are elevated above the superficial skin. We distinguish the simple nievus pigmentosus of black, brown or light color, the nsevus pigmen tosus verrucosus with a warty, knobby surface, the naavus pigmentosus spilus (with a smooth surface) and the mertes piliferus (covered with hair). The 11X Vi grow with the body, and all forms may be found to gether on one individual. if a IITIMS extends over a large area of the body, we speak of a giant ntevus: if it is besides covered with hair resembling animal skin, covering the abdomen, pelvis and femoral region, we speak of a bathing suit nmvus (Kaposi). The smallest puncti form na)vi arc called lentigines.
Besnier and Jadassohn have grouped a number of nmvi which were described under the nanaes of nerve umvi, ntevus unius lateris (Baren sprung), linearis verrucosus (Unna), together under the collective name of systematized nievi, in order to indicate that for the develop ment of these mevi certain sites or conditions of development arc in fluential. The systematized nrevi are to be found in the course of nerves or of Voigt's demarcation lines (the branch regions of the skin DerVeS, Philipsohn), or in the course of the hair currents (following their lines of convergence and divergence), or in a certain metameric arrangement, especially at the back (Peeirca, Ilallopeati), the arrangement being thus always different, but always demonstrable, and certainly influ enced by the development of the skin. These nievi often produce considerable itching, they may also become easily ualematous and may during infancy cause trouble enough to render operative interference or galvanocaustic treatment necessary (Galewsky-Schlossmann).
Pathological we find ft large accumula tion of cells in the cutis fru-evils cells), a considerable accumu lation of pigment in the rete and corium. and very often a strong proliferation of the cones and papilla-.
Etiology.—The cause of ruevi is not known, although in many eases heredity can be demonstrated. In how f ar they may be occasioned by the pregnant mother receiving a psychic impression of similar growths, remains to be demonstrated.
progno sis of nTvi in childhood is benign, although they some times require treatment on account of itching and development of eczema. Generally nrevi develop gradually, then stand still, while in other cases they will gradually disappear. In advanced age they may be transformed into malignant ulcers.
Among the organic na?vi those best known and most frequently occurring arc the mevi vasculares (angiomatosi, flanunei), the well known circumscribed anomalies w-hich originate from the vessels and are popularly- known as fire moles. The simplest form of these are the punctiform or stellate telangiectases fmvvi aramei) which are frequently found in the face of the youngest infants and consist of a hypera•mic central blood vessel and a number of smaller vessles which radiate from the same. The large fire moles may occupy large areas of the body and have a most disfiguring effect. The vascular na,ri are either present at birth or develop later; often they disappear again after birth. They occur in all sizes and colors, singly or in groups, chiefly at the temples and cheeks, but also at the occiput, the root of the nose, the eyelids ancl thc extremities, they are sometimes superficial and sometimes deeper, and may even spread to the mucous membrane. They may remain simple angiomata or form combinations with other tumors (sarcomata, etc.).
Among the glandular ntevi in children there are the so-ealled navi sebaceit (adenomata sebacea), small tumors of the sebaceous glands in the nasolabial fold and at the cheeks, of red, yellowish or white color.
Concerning the etiology of angiomata we. are likewise ignorant,. Aside from the disfiguring effect and the very rare cases in which angio inata become malignant, the prognosis is good.
Treatment.-1. Ephelides.—The treatment of freckles demands protection against the rays of the sun and depigmentation. The pro tection from the sun in sensitive children (especially the blonde) is effected by wearing veils dyed with chrome or curcuma, or by painting the skin with a 10 per cent. quinine and gelanthum solution. Depig mentation is effected by corrosive sublimate, white precipitate, per oxide of hydrogen and oxychlorate of bismuth; for instance hydrog. peroxide 20.0 Gni., bism. oxychlori 0.5 Gm., sublim. 0.03 Gm., adeps lana 10.0 Gm., vaselin 20.0 Gm.
2. Ncrri.—The treatment: of 11:I'Vl IS one of destruction and can be carried out by cauterization with 1 to 10 per cent,. sublimate collo dium or trichloraeetic acid or silver nitrate. The quickest effect is obtained by the Paquelin or galvanocautery. The best cosmetic results are obtained by electrolysis (positive pole in the hand, negative pole with the needle through the skin under the ncevus, piercing in all direc tions two minutes each time, current of 5 NI.A.).
3. Angiornata.—Their removal in the case of very small telan gieetases in early infancy is best done, according to Drina, with ichthyol collodium (1 to 10 per cent., painting afresh as the cover is lifted). larger angiomata are being excised, small and medium ones are removed by electrolysis (see above) or treated by the Finsen-Reyn lamp, or by radium exposures of 15 to 30 minutes duration (caution!).