2. Cauwenberghe considers the changes in the villi and the umbilical vessels as secondary, and repeats Bustamente's views, but he agrees with Hegar and Maier that the walls of the large vessels, on the fcetal placental surface, are thickened from hypertrophy of the tunica adventitia, the lumen. of the vessels being contracted and the capillaries empty.
Ercolani, 1876, considers the villi to be formed of two parts, the par enchyma, (chorial tissue of Robin; mucous tissue of Virchow), in com munication with the chorion and the external part or epithelial envelope. He distinguishes, among .diseases of the villi, hypertrophy or myxoma of Virchow; hydatigenous placenta; myxoma of the serotina or of the glandular organ surrounding the villi. The first two lesions correspond to the vesicular mole of the books. Here is his description of myxoma of the serotina: The placenta belonged to an abortive fcetus of three or four months. It was normal and completely developed. The supposed placental parenchyma was composed of an intricate net of villi, between the chorion and the serotina. The microscope showed in the pedicles and tufts of the villi, irregular swellings formed by a layer of the cells of the serotina. In the cells the development of the glandular organ was arrested and little pediculated bodies, generally pyriform, had appeared. Some of these, Virchow's physcolides, contained liquid such as we say, in the epithelial proliferations of the villi. The parenchyma of the villi had undergone atrophy and fibroid degeneration at the beginning of its devel opment.
Ercolani considers the fibro-fatty degeneration of the placenta a cellular hypertrophy of the parenchyma of the fcetal villi, simple or complicated by vascular obliteration and glandular atrophy. He considers the hyper plasia of the cells in the mucous tissue of the villi, to be peculiar to the disease.
Dilatation of the vessels seems to be the result of the obstacle opposed to the circulation by obliteration of vessels in some of the tufts of the villi. The reason for the obliteration is the pressure exerted on the ves sels by tbe neighboring cells, which are greatly increased in number and in volume. The volume of the diseased villi is augmented and they form compact, grayish masses, because they have no vessels and because the maternal blood cannot circulate around them. This is the lesion des cribed by Bustamente and Neumann 11.13 sclerosis of the placenta.
Ercolani also describes fibroma of the villi and of the serotina. Called fibro-fatty degeneration by Robin, and designated as syphilitic by Virchow, this lesion is frequently found, according t,o Ercolani, on abortive pla centas expelled after the third mouth or on placentas at term. In the latter it is less extensive. In the beginning of the transformation of the mucous tissue of the villi into fibrous tissue, the cells become more elliptical and numerous, and the surface seems firm and almost vitreous. Ercolani regards this really as a hyaline transformation and not as a fibroid one, because amorphous transparent matter abounds in the cells.
The fibrous transformation is now partial, noyi general. Obliteration of the vessels in the villi is secondary. The fibrous change may affect the villi alone, or also involve the glandular organ. The change may occur simultaneously in the villi and the serotina, before the glandular organ is formed. When the cells of the serotina assume the character of fibrous tissue, they remain round but get smaller, arrange themselves in series, lose their granules, and their nucleus is rapidly colored red with carmine.
Later, the nyaline substance exudes through the cell walls, and the cells, losing their round form, take on that of the connective tissue corpuscles, having numerous inter-communicating poles. The vessels of the villi are mostly obliterated. The fibrous tissue of the serotina is fused with the new fibrous tissue of the villi.
Ercolani and Beluzzi also mention melanosis of the placenta, consisting in the deposition of pigment granules around the utero-placental vessels or in the villi. The pigment is hematoidin.
Ercolani states that there may be thrombosis of the sinuses and hem orrhage. The decidual vessels may rupture in the early months, and cause hemorrhage between the decidua and the chorion. The chief cause of the clots and hemorrhages is fatty degeneration of the cells of the serotina. The cella, thus altered, support, but poorly, the pressure of the blood in the lacunte, a,nd hemorrhage results. He has never observed the transformation of the coagula into pyoid matter, pus or neoplasms. He, however, remarks that the diversity of color in apoplectic centres, does not only depend on the time and character of the changes, but also on the quantity of lacuna] blood and on the relative rapidity of coagu lation.