Paper - A study of the causes underlying the origin of human monsters 14
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Mall FP. A study of the causes underlying the origin of human monsters. (1908) J Morphol. 19: 3-368.
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A Study Of The Causes Underlying The Origin Of Human Monsters
Pathological Embryos or the Second Week
The preceding pages have been devoted to the discussion of those pathological ova in which the embryos were nearly or entirely destroyed, leaving only the membranes. A large number of these specimens appeared to be normal ova when examined superﬁcially, but careful examination showed that in many of them mucus, leucocytes and pus were present between the villi. In many the chorion was thickened and more or less invaded by leucocytes and syncytium, while in others the cavity within had been obliterated completely to form typical ﬂeshy moles. We have in them all stages of transformation between young normal ova and solid moles.
The specimens in the preceding sections are easily divided into two groups: the ﬁrst, in which the embryo and the amnion are destroyed, and the second, in which the embryo is destroyed but the amnion and more or less of the cord remains. In each of these groups there are intermediate stages which may be properly considered under this heading. In the ﬁrst group these changes began in very early specimens, and in some of them the destruction of the embryo and amnion was not always complete. These might properly be considered with the embryos given in Table V, but I have found it more convenient not to do so and have included in this and subsequent tables only those embryos in which the form and structure could be made out with considerable certainty. . By doing this there is still a wide margin left for the imagination in linking the pathological specimens of a given week with normal embryos. After this has been done it is easier to correct errors than it is when the specimens in which the embryos have been destroyed are grouped with atrophic ones. My arrangement for the present is as follows:
- Normal embryos.
- Atrophic embryos.
- Remnants of atrophic embryos.
- Ova with amnion but Without embryos.
- Ova with neither amnion nor embryos.
What has been said about ova with neither embryos nor amnion applies equally well to those in which the amnion is not destroyed. In this group there are also all intermediate stages present, and they can be arranged in a series, if considered alone, for if the embryo is present there is also an amnion, and adding them spoils the group. The group given in Table IV could, therefore, be scattered under the following headings, but this is not convenient, because the absence of the embryo makes it difficult to determine at what time the pathological changes in the embryo began, and, furthermore, it is easier to consider alone those specimens in which the amnion is present with more or less of the cord, including an occasional fragment of the embryo. This group blended with embryos over four weeks old would compel us to subdivide those of each week as follows:
- Normal embryos.
- Atrophic embryos.
- Remnants of atrophic embryos attached to the umbilical cord.
- Umbilical cords alone.
- Ova lined with an amnion alone.
- Moles with remnants of the amnion present.
With this brief introduction, I shall proceed to consider pathological ova in which the development of the embryo is arrested, beginning with those of the second week. In my ﬁrst Contribution there were none belonging to this list; in the second Contribution there was one. I now have three new ones (including No. 12) to add.
TABLE V. Axuuasran DEVEDOPMENT or rm: EMBRYO. (Second Week.)
No. Embryo. Chorion. MERE?-_“a1 ) Changes in the Chorion. mm. mm. days 162 I. 70 x 30 X 30 81 Atrophy. 250 2. 1ox9x9 Leucocytic inﬁltration of decidua, chorion normal. 32: 2. 40 x 40 x no 12 2.: 2o 2: 2o 41 Small amount of mucoid mass Nor- between villi.
mal ( ?)
The embryo of specimen No. 162 is one millimeter long. with structures which would make it as old as Eternod’s or Graf Spee’s, given in Table I. The chorion is very thin, devoid of villi and enveloped in layers of coagulated blood. Through this but little nutrition could have come to the embryo, if it got any at all. The amnion ﬁlls the entire chorion and its cavity measures 35 x 12 x 12 mm., although the whole specimen measures 70 x 30 x 30 mm. According to the menstrual history the age of the specimen is at least ﬁfty-three days, and if we deduct thirteen days, the age of the embryo when it ﬁrst became affected, then the pathological process must have continued during forty days. Sections of the embryo show that we are dealing with a remarkable specimen, in which great changes have taken place gradually. All of the organs and tissues are dissociated, that is, they have grown in an irregular manner, each one growing by itself, not being markedly inﬂuenced by the surrounding structures. The different tissues are not of uniform structure, being mucoid in some places and necrotic in others, as is shown in the ﬁgure. The mucoid tissue runs as a column from the heart to the apex of the nodule and may have been derived from the chorda dorsalis. At the point of union between the amnion and chorion there are three elevations from the embryo mass into the coelom. These are marked in the ﬁgure. The heart lies within a pocket of its own, which communicates with the exocoelom and is ﬁlled with blood. There are also blood-vessels ﬁlled with blood in the center of the embryo.
This interesting specimen of a dissociated embryo, that is, one in which the tissues grew in an irregular fashion, is accompanied with another excellent one, No. 250, in which these changes are just beginning. In many respects it is normal, and for this reason I have also included It in Table I as an embryo of the fourteenth day. The ovum and decidua were curetted from the uterus and came to me opened and well preserved. The presence of an excess of magma reticulé gave the hint that the specimen was not quite normal.
The chorion, villi, syncytium and decidua are beautifully developed and are normal in structure. Between the villi there is much mother’s blood and within them there is a welldeveloped system of capillaries ﬁlled with embryo’s blood. There are numerous leucocytes in the decidua, but they do not form abscesses.
The front end of the amnion is wanting and its free ends are well imbedded in reticular magma, showing that this injury took place before the abortion was produced. The embryo is normal in form, the heart and blood—vessels well developed and ﬁlled with blood. The rest of the organs are about of the same stage at No. 391, an embryo of the fourteenth day. The tissues of the embryo and the ventricle of the fore-brain are ﬁlled with numerous small round cells with fragmented nuclei. Most of the blood corpuscles are still within the blood-vessels, but those within the tissues are perfectly normal and in no way do they seem to give rise to the strange cells in the tissues. However, it may be noted that the mesodermal cells are diminished in number in those tissues in which the round cells are present, which indicates that the one changes into the other. The primary histological change in this embryo is found in the mesoderm, which is dissociating to form some of the so—called wandering cells. Later this process affects the wall of the vascular system and the blood cells escape into the tissues, as was pointed out by His. The cells within the ventricle of the brain as well as those of the neural tube are mostly fragmented and have between them a few normal blood corpuscles. It is probable that most of these new cells arise from the dissociated nervous tissue. I shall come back to this question from time to time as I discuss specimens which have changes within them that bear upon this point. However, this much is clear: the round cells with fragmented nuclei lying within the tissues have not emigrated from the blood, but, instead, have arisen by a process of dissociation of the tissues within which they lie.
The process of dissociation, begun in No. 250, is carried to an extreme degree in No. 321. Both of the embryos are of the same size, but in the second the amnion and chorion have continued to grow. The chorion is normal in appearance and is lined entirely by the amnion, the cavity of which is 35 mm. in diameter. It is interesting to note that this ovum has reached its maximum growth without the presence of a vigorous embryo. Ova without embryos rarely exceed 40 mm. in diameter, and in normal development the amnion reaches the chorion and obliterates the exocoelom in ova of this size. If the cavity of the amnion is to exceed 40 mm. in diameter, it is necessary to have a fairly active embryo within it to secrete the liquor amnii. As long as there is an exocoelom present, which is not obstructed by magma reticulé, it appears as if ﬂuid of the amnion is obtained from that of the coelom.
In this specimen (No. 321) the embryo is attached to the chorion at its middle, that is, there is no umbilical cord left. The body cavity of the embryo spreads out on the inside of the chorion, and into this the degenerated heart hangs. The dissociation of the tissues is pretty complete, as in No. 162. The outline of the brain is barely recognizable and all the tissue in the tail of the embryo is of equal density. Here the dissociation is complete. Unfortunately, the specimen had been preserved in 50 per cent alcohol for ten days before it was sent to me, and in a measure the extreme degree of dissociation may be due, in part at least, to the macerative inﬂuence of the Weak alcohol. However, this could not alter the general outline of the embryo and its organs.
No. 12 is extremely interesting, for it also is probably pathological, although I have often referred to it as being normal. When it came to me I found considerable magma in the coelom, enough to almost obscure the embryo, but on account of the general normal structure of the tissues I overlooked the excess of magma. More careful investigation of the chorion shows that there are also some ﬁbrinous or mucoid masses between the villi. They also indicate that the specimen is not quite normal. Furthermore, there is a marked anencephaly and probably the beginning of spina biﬁda present. Before a deﬁnite opinion can be given regarding the normality of this specimen it will be necessary to examine with much greater care than has been done the tissues of the embryo, and especially those of the chorion of many so-called “normal” specimens. This will be done, no doubt, in the near future.