328 HYDATIFORM DEGENERATION IN TUBAL AND UTERINE PREGNANCY. 



tion the case of Otto (1871), or that of Wenzel (1893), and he incorrectly credited 

 Wenzel with two cases. Werth, on the contrary, regarded these last two cases, and 

 also that of Croom (1895), which is accepted also by Veit (1899), as undoubted 

 instances of "simple hydropic degeneration of the connective tissue of the villi so 

 common in aborted chorionic vesicles, both from the tubes and from the uterus." 

 Werth unfortunately does not state just what he means by simple hydropic degen- 

 eration, but since he speaks of it as common in aborted ova, one may conclude that 

 he refers to changes in the chorionic vesicle which have followed its isolation within 

 the uterus after complete detachment from its implantation site. For want of a 

 better term, such changes may, I presume, be spoken of as maceration changes, 

 although usually they occur under non-putrefactive conditions. However, I do not 

 thereby imply that these changes are similar under sterile and under putrefactive 

 conditions. 



Since Werth speaks of simple hydropic degeneration in aborted ova he does 

 not, I take it, refer to a dropsical condition of the villi possibly due to an obstruction 

 of the venous return, for such a condition necessarily would be rare and not com- 

 mon. Moreover, this condition of necessity would have to arise before and not 

 after the death of the embryo and detachment of the chorionic vesicle. As in one 

 of the cases of Hicss (1914), such a specimen also should contain blood-vessels 

 for, as emphasized also by Ballantyne (1913), the hydatiform villus is not merely 

 an edematous villus. 



That any one at all familiar with hydatiform degeneration, in its earlier as 

 well as its later forms, upon gross and microscopic examination, could confuse it 

 with maceration changes in a fairly well-preserved specimen in any but its very 

 earliest stages does not seem possible to me. Normal villi contain capillaries, not 

 to mention other things characteristic of them. Hydatiform villi, on the contrary, 

 do not contain them, or only very rarely so, and in the early stages. When a villus 

 becomes hydatiform that is, when liquefaction of the stroma occurs this lique- 

 faction appears in more or less restricted portions of the villus, thus giving rise to 

 the long fusiform and later spherical vesicles so characteristic of hydatiform mole. 

 But when a villus becomes macerated the change is general, and usually also is 

 noticeable in the embryonic and chorionic membrane itself, or at least within the 

 epithelium. The latter usually is lifted from the stroma here and there, the caliber 

 of the entire villus is increased, and the capillaries and the stroma show maceration 

 changes as the villus becomes more translucent. This increase in caliber of the 

 entire villus is not due to local liquefaction of the stroma, but to the pseudo-edema 

 occurring in a villus of normal structure and form. In hydatiform moles, on the 

 contrary, the epithelium not only is firmly attached but usually hyperactive. The 

 changes characteristic of hydatiform degeneration may and often do appear in 

 the villi while they still are implanted, and not only after the chorionic vesicles 

 are detached. This does not imply, however, that the villi of a detached hydati- 

 form mole can not also undergo maceration changes. They, of course, frequently 

 do so, and it is in such cases as these that differentiation may be difficult or impos- 

 sible, especially if it is to be made from an examination of ill-preserved fragments 



