Licence: Public Domain Mark
Credit: A text-book of pathology / by Alfred Stengel. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
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![cells take up tiio fluid. In burns find pemphigus and in other skin-lesions connectcnl with vesiculation, and in various inflamma- tions of organs, edema of the cells occurs. It is also a part of the degeneration termed cloudy swelling. The cells are enlarged, often to an extreme degree, and they may even burst. The protoplasm sooner or later becomes cloudy and often presents degenerative changes—fatty metamorphosis in particular. Vacuolation is frequently observed (Fig. 18). The condition is probably a purely physical phenomenon in the dropsies. In the cutaneous lesions other factors are operative. CALCIFICATION. Definition.—Calcification consists in the abnormal deposition in tissues of earthy salts. The phosphates and carbonates of cal- cium are the chief salts concerned; the oxalates, however, are usually present, and the corresponding magnesium salts may be mixed with them. The best physiologic examples are the senile change in the vascular apj^aratus and the formation of the brain- sand (acervulus cerebri). Impregnation of the skeletal tissues is usually accomplished as a physiologic condition througli the activ- ities of special cells; this is an essential element in ossification. i^tiology.—The deposition generally occurs in diseased tis- sues, especially in those the seat of vascular disorders. Local necrosis or fibrosis antedates intercellular calcification, and the process may be accompanied by atrophy and absorption of certain cellular elements. In neoplasms the abnormal cellular conditions obviously predispose; but here, too, the vascular relations are of notable importance. Hyaline and fatty degenerations often pre- cede or accompany it. In rare instances no local predispositions can be determined. Cases of this kind occur in old age, and for these it is inferred that owing to increased lime-resorption from the skeleton the system is saturated to the point of precipitation. Similar snpersaturation of the blood with calcareous matter may occur in cases of extensive disease of bones, and may lead to wide- spread de])osition. Pathologic Anatomy.—Early in the process no macroscopic signs are apparent. On microscopic examination the salts are seen as fine granules scattered through the intei'cellular substance. Cel- lular infiltration, however, is not imcommon, and in such instances the cells show more or less extensive nuclear and protoplasmic degenerations. By the coalescence of the granules larger, irregular spherical bodies may be formed. These usually have a concen- tric arrangement (psammoma bodies). Definite crystals are rare, but may be seen. The next adjacent tissue may ])resent an opaque appearance. In certain localities, especially tlie blood-vessels and serous membranes, calcareous plates are formed. The depositions 8](https://iiif.wellcomecollection.org/image/b21981668_0083.jp2/full/800%2C/0/default.jpg)
