(B) CHRONIC GOITRE.—I. Congenital. —This may be of very varying forms, as above indicated in Wolfler's classifica tion. It is relatively rare.
II. Vascular Goitre.—This is most. frequently due to a distension of the abundant venous plexus of the gland; the organ is generally enlarged and is liable to press upon the trachea, causing modification of the voice and not infre quently paroxysmal attacks of dysprima simulating asthma. As above stated, this form may develop acutely.
III. Parenchymatous Goitre.—Under. this heading is to be grouped the vast majority of cases of the disease. We have to recognize that, both in the gen eral hyperplastic form and in the nodu lar, there may be great variation in the changes which occur. But these changes appear to be essentially connected with alterations in the structure and functions of the follicles.
1. Thus in one large class of cases there is, as the most prominent feature, a great storing up of the colloid material within the follicles, of isolated lobules of one lobe, or of the whole organ, and even in the lymph-spaces and—some would say — the blood-vessels of the gland. This is a form generally spoken of as colloid goitre, or struma gelatinosum.
2. Adenomatous Goitre.—In other cases we have to deal with the very opposite condition of marked overgrowth of the glandular epithelium in the more or less embryonic condition with little develop ment of colloid.
3. Cystic Goitre.—Whether we are dealing with the colloid or adenomatous type, there is a liability to cystic forma tion. In the colloid variety occasionally such cysts may be of the nature of reten tion-cysts and may resemble in their development the emphysematous bully met with in the lung, several follicles, through atrophy of their walls, fusing into one. But more frequently such cysts, as was pointed out years ago by Ilokitansky and of late by Bradley, are of luemorrhagic origin, the new growth in the gland being very vascular and the position of the organ and its varying blood-supply rendering the vessels pecul iarly liable to rupture. Hence, are pro
duced smaller or larger spaces filled with albuminous fluid, more or less tinged with modified blood-pigment, corre sponding in every respect to the cysts which may develop in the brain after hemorrhage in that organ.
Case of acute enlargement of the thy roid gland in chronic parenchymatous nephritis. The enlargement was due to a dropsy of the gland. The serous cavi ties were free from effusion. This con dition regarded as a vasomotor neurosis in association with Bright's disease. W. A. Edwards (Inter. Med. Mag., Apr., '92).
Uurther changes may occur in such parenchymatous goitres: there may be hyaline or mucoid degeneration, calcifi cation, intra-acinous growth, or the eventual development of cancer.
4. Malignant parenchymatous goitre, or primary carcinoma of the thyroid, as above stated, would seem almost to orig inate in a gland which may, for years, have been the scat of a more or less sta tionary parenchymatous goitre.
IV. Interstitial goitres are relatively rare. 1. Among the benign forms may be recognized the myxomatous goitre, which is, in general, a parenchymatous or adenomatous goitre in which the inter stitial tissue has undergone mucoid de generation. 2. Fibroid goitre is always nodular, the nodules being recognized by their peculiar firmness and hardness. 3. Malignant interstitial goitre, or sarcoma, which is relatively rare, is characterized by its peculiarly rapid growth and by its tendency to ulcerate and to extend into the trachea or externally.