216 STUDIES ON PATHOLOGIC OVA. 



2077 (shown in natural size in figure 100), which attract no attention upon cursory 

 inspection, may, and often do, present the most exquisite picture of hydatiform 

 degeneration when seen under a magnification of 3 to 20 diameters, as illustrated 

 in figure 101. This is true especially if the examination is made with the binocular 

 microscope. Since I have adopted this method of examination it has been possible 

 to recognize instances of decidedly general and typical hydatiform degeneration 

 in chorionic vesicles less than 2 cm. in size, with later confirmation of the diagnosis 

 by a histologic examination. However, I have not been able to recognize very 

 early stages merely by examination of the gross specimens, for gross recognition 

 is possible only when portions of at least some of the villi have become sufficiently 

 elliptical or globular to attract attention. Histologic recognition is possible far 

 earlier than this, as shown in figure 102. 



The general appearance of the whole chorionic vesicle is sometimes an aid in 

 gross identification, for the villi not infrequently are smooth, slightly branched, 

 and unusually long, so that the vesicle looks shaggy, as illustrated in figure 103. 

 Several hydatiform villi from this specimen are shown in figure 104. The typical 

 gross hydatid or watery, translucent nature of the villi can not be relied upon 

 in early stages, for normally shaped villi that have undergone considerable lysis 

 may be almost transparent and also somewhat more than normally bulbous. 

 However, save in the case of some specimens of tubal pregnancy, the swelling of the 

 villi, due to maceration or to luetic changes, is quite different in character from 

 that characteristic of hydatiform degeneration, and usually quite easily distinguish- 

 able from it. Judging from several specimens of villi which were macerated in 

 distilled water during a period of weeks, post-partum maceration never should 

 cause confusion, and the same thing undoubtedly is true of intrauterine macera- 

 tion. The differences in appearance between macerating villi with disintegrating 

 epithelium, stroma and blood-vessels, and others undergoing hydatiform degen- 

 eration, is well illustrated by villi from No. 640, shown in figures 105 and 106. 

 Though photographs can not register all the distinctions, the contrast is so marked 

 in this case that one can not fail to notice it. 



Since numerous trophoblastic nodules are present also in other conditions, 

 notably in retained placentae, as found by Aschoff and others, I have not been able 

 to regard their presence in unusual numbers, in some cases of hydatiform degenera- 

 tion, as of crucial value, but the absence of placental differentiation at a time when 

 it should be present, with a uniform and unusual development of the villi over the 

 whole exterior of relatively large chorionic vesicles, is decidedly significant and has 

 often been found to imply the presence of hydatiform degeneration. The same 

 thing is true of a very irregular distribution of the villi, or of uniformly distributed 

 fusiform enlargements on the villi and of the loss of the dull appearance of their 

 cut surfaces, as seen under the binocular. As soon as the stroma becomes hydati- 

 form, and even before liquefaction is present, the cut surfaces of hydatiform villi 

 look somewhat shiny and waxy or, perhaps better still, paraffine-like. This was 

 well shown in a previous paper (Meyer, 1920, fig. 21). A bluish tinge is always 

 present, and this appearance is very characteristic. However, how easily a speci- 



