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The much larger series of abortuses composing the entire collection also includes unique specimens which are the product of some rare experiment on the part of nature. One is much less likely to find such specimens in a smaller and hence less representative collection. What is lacking, however, in connection with many of the specimens, otherwise so valuable, is the decidua. In the absence of the latter it is often impossible to reach even a tentative conclusion regarding the genesis of the abnormalities found in a particular specimen. In many instances this defect could be easily remedied by an appeal to our many coworkers and benefactors engaged in the practice of medicine. I am certain that they will gladly save the decidua whenever possible, merely as a matter of cooperation, although it need not be forgotten that the assistance we can give to donors when reporting our findings is very largely contingent upon its preservation. It is true that in the course of time, and even now to some extent, we shall be able to give a report suggestive of the possible intrauterine conditions from an examination of the conceptus alone, and just in proportion as our knowledge of the condition of the decidua increases this opinion will become more reliable, and hence also of more practical value.
The much larger series of abortuses composing the entire collection also includes unique specimens which are the product of some rare experiment on the part of nature. One is much less likely to find such specimens in a smaller and hence less representative collection. What is lacking, however, in connection with many of the specimens, otherwise so valuable, is the decidua. In the absence of the latter it is often impossible to reach even a tentative conclusion regarding the genesis of the abnormalities found in a particular specimen. In many instances this defect could be easily remedied by an appeal to our many coworkers and benefactors engaged in the practice of medicine. I am certain that they will gladly save the decidua whenever possible, merely as a matter of cooperation, although it need not be forgotten that the assistance we can give to donors when reporting our findings is very largely contingent upon its preservation. It is true that in the course of time, and even now to some extent, we shall be able to give a report suggestive of the possible intrauterine conditions from an examination of the conceptus alone, and just in proportion as our knowledge of the condition of the decidua increases this opinion will become more reliable, and hence also of more practical value.
NOTE In view of the suggestions made in Science (A. W. Meyer, 1919: A suggestion from Plato, with others, vol. 49, p. 530) some of which have been incorporated in the following pages, the title of this volume demands a word of explanation. I have retained the word ova because the title had in part been decided upon. Moreover, the word is still used in this sense in current medical literature, but we are not considering ova but conceptuses. Besides, a considerable percentage of these undoubtedly are not pathologic or diseased, for surely post-mortem changes in structure, however profound, can not strictly be regarded as pathologic; and since derangement of function is made impossible by death, no matter how deformed or how infiltrated the tissues of an abortus may be with the cells of maternal origin, it can not therefore be said to be diseased. A. W. M.




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A. W. Meyer.
A. W. Meyer.
----
NOTE In view of the suggestions made in Science (A. W. Meyer, 1919: A suggestion from Plato, with others, vol. 49, p. 530) some of which have been incorporated in the following pages, the title of this volume demands a word of explanation. I have retained the word ova because the title had in part been decided upon. Moreover, the word is still used in this sense in current medical literature, but we are not considering ova but conceptuses. Besides, a considerable percentage of these undoubtedly are not pathologic or diseased, for surely post-mortem changes in structure, however profound, can not strictly be regarded as pathologic; and since derangement of function is made impossible by death, no matter how deformed or how infiltrated the tissues of an abortus may be with the cells of maternal origin, it can not therefore be said to be diseased. A. W. M.





Revision as of 02:15, 20 November 2012

Studies on Abortuses: A Survey of Pathologic Ova in the Carnegie Embryological Collection

title page

VOLUME XII, No. 56

PUBLISHED BY THE CARNEGIE INSTITUTION OF WASHINGTON WASHINGTON, 1921

CARNEGIE INSTITUTION OF WASHINGTON PUBLICATION No. 275

PRESS OF A. B. GRAHAM CO. WASHINGTON

CONTRIBUTIONS TO EMBRYOLOGY

No. 56. STUDIES ON ABORTUSES: A SURVEY OF PATHOLOGIC OYA IN THE CARNEGIE EMBRYOLOGICAL COLLECTION.


By Franklin Paine Mall and Arthur William Meyer.


With twenty-four plates, five text-figures, and one chart.


Links: Carnegie Institution of Washington - Contributions to Embryology

Contents

Preface. By A. W. Meyer

Chapter I Origin of the collection. By F. P. Mall

Chapter II Care and utilization of the collection. By F. P. Mall

Chapter III Classification. By A. W. Meyer

Chapter IV Analysis of abortuses classed as pathologic. By A. W. Meyer (Plates 1-6)

Group 1 : Specimens composed of villi only
Group 2: Chorion without amnion or cyema
Group 3: Chorion with amnion
Group 4: Chorionic vesicles with nodular cyemata
Group 5: Cylindrical cyemata
Group 6: Stunted cyemata
Group 7: Fetus compressus
Summary
Protocols

Chapter V Relation of cyemic to chorionic size. By A. W. Meyer

Chapter VI. Sex incidence in abortions. By A. H. Schultz

Chapter VII. Occurrence of localized anomalies in human embryos and fetuses. By F. P. Mall (Plate 7)

Chapter VIII. Hydatiform degeneration in uterine pregnancy. By A. W. Meyer (Plates 8-12)

Chapter IX. Hydatiform degeneration in tubal pregnancy. By A. W. Meyer (Plate 13)

Chapter X. The alleged occurrence of superfetation. By A. W. Meyer (Plate 14)

Chapter XI. Ovarian pregnancy. By F. P. Mall and A. W. Meyer (Plates 15 and 16)

Chapter XII. Lysis and resorption of conceptuses. By A. W. Meyer

Chapter XIII. Postmortem intrauterine changes. By A. W. Meyer (Plates 17-19)

Chapter XIV. Hofbauer cells in normal and pathologic conceptuses. By A. W. Meyer (Plate 20)

Chapter XV. The villi in abortuses. By A. W. Meyer (Plates 21-23)

Chapter XVI. Villous nodules. By A. W. Meyer (Plate 24)

Chapter XVII. Changes suggestive of lues. By A. W. Meyer

Chapter XVIII. Some aspects of abortion. By A. W. Meyer

Bibliography.

Figures.


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Preface

The following survey comprises a review and an analysis of conceptuses which are classed as pathologic in the first 1,000 accessions to the collection of the Department of Embryology of the Carnegie Institution of Washington. The majority of these accessions were included in the Johns Hopkins Medical School collection. They had been collected with untiring effort by Professor Mall, with the generous cooperation of numerous physicians, both at home and abroad, during the course of two decades. The accompanying studies on special topics are not, however, so limited, nor are they confined to pathologic conceptuses only. Although closely related, they aim neither at completeness nor even at unity, except as individual contributions. Since, with the exception of the tables, the survey proper is limited to the first 1,200 accessions, with only such references to the remainder of the collection as time permitted, it is very probable that some of the results and conclusions drawn from them will not be fully supported by an extension of this study to the material in the entire collection. This is due not only to the fact that the abortuses received more recently are better preserved and that the later histories are fuller, but also to the increasingly closer cooperation with clinicians which often brings us very helpful clinical sidelights. Indeed, it is this cooperation which alone can enable us satisfactorily to develop certain aspects of the new field of antenatal pathology, and help to bring a final answer to some of the many unsettled questions. Without the information which the practitioner alone can furnish one often feels helpless; for although many of the specimens are eloquent with facts, others remain entirely mute as to their story because they appear wholly normal.


The much larger series of abortuses composing the entire collection also includes unique specimens which are the product of some rare experiment on the part of nature. One is much less likely to find such specimens in a smaller and hence less representative collection. What is lacking, however, in connection with many of the specimens, otherwise so valuable, is the decidua. In the absence of the latter it is often impossible to reach even a tentative conclusion regarding the genesis of the abnormalities found in a particular specimen. In many instances this defect could be easily remedied by an appeal to our many coworkers and benefactors engaged in the practice of medicine. I am certain that they will gladly save the decidua whenever possible, merely as a matter of cooperation, although it need not be forgotten that the assistance we can give to donors when reporting our findings is very largely contingent upon its preservation. It is true that in the course of time, and even now to some extent, we shall be able to give a report suggestive of the possible intrauterine conditions from an examination of the conceptus alone, and just in proportion as our knowledge of the condition of the decidua increases this opinion will become more reliable, and hence also of more practical value.


The chief reason why the decidua, or the membranes, or the placenta are not preserved oftener is that physicians have not fully realized that they are needed and wanted. A mere reference to the protocols and summaries will illustrate in how large a percentage of the cases it is not included at present. Although I fully realize that often it is impossible for the physician to secure it, and that in other cases it is of little value even when secured, I am certain that the percentage of cases in which it is missing can be greatly reduced in the future with consequent mutual benefit. The closest cooperation with clinicians is necessary, not only in order to secure the necessary material, but also to obtain further information through supplementary observations upon the living patient. Only in this way can the great gap left in human obstetrics and embryology, by the impossibility of performing experiments, be partly filled. In the case of animals, experimentation no doubt will eventually determine for us the relationship of teratology to pathology, but in the case of man this relationship must be determined very largely by observation alone, for although every instance of human gestation under abnormal conditions answers to an experiment, such experiments must always remain uncontrolled, and the exact conditions which usually obtain must remain unascertainable. Nevertheless, the practitioner, with the patient's help, frequently can bear witness as to the conditions under which nature's experiment was performed and as to the sequence of crucial events, and it is on the unselfish efforts of physicians that we must depend for assistance in this matter.


Mall did a very great service in calling attention to the fact that abnormalities of the fetus are frequently associated with, even if not always or necessarily produced by, uterine diseases. The relationship between the two is revealed still further, especially in Chapter IV, and further investigation of this subject ought to bring to light facts not only of further scientific interest, but pregnant with great humanitarian service. It is startling indeed to observe what a monstrous fetus may accompany an apparently moderately diseased chorion, and it is equally startling to observe that a chorionic vesicle apparently normal may be wholly devoid of an embryo. But here we meet one of the obstacles in the way of present progress, for we do not yet know exactly what a normal ovum or villus looks like in all stages of development. Both must yet be standardized, and for this standardization a knowledge of the condition of the decidua and of the probable cause of the abortion will be extremely helpful. If all early conceptuses were undoubtedly normal, the problem would be a simple one; but very many are abnormal or atypical at least.


As our knowledge of the normal becomes more complete, we find that more and more young embryos which formerly were regarded as normal are not really so. The literature of human embryology contains many such instances, and it was impossible, and it remains impossible even at the present time, to determine in all cases whether we are dealing with a normal or an abnormal specimen, even after it has been mounted in serial sections. Hence it happens that abnormal human embryos and fetuses still are represented as normal in contemporary embryologies. It has often seemed to me that there is one source of material which could bring much help in this connection. If the many tragedies with which our coroners come in contact could always be utilized scientifically, as they rarely have been in the past, much desired information would soon be in our possession. It seems that a very promising opportunity for progress lies here. In an intelligent community public opinion will, I believe, gladly support any one in such utilization of these chance cases as soon as a broadly humanitarian, even if not a keenly scientific, attitude can be cultivated on the part of our coroners.


What can be accomplished through cooperation between public officials and laboratory workers was illustrated by the fine assistance given Professor Mall and the Department of Embryology of the Carnegie Institution of Washington by the department of health of the city of Baltimore. Indeed, one can not recall this service without feeling the deepest regret that similar cooperation, especially with coroners, has not yet been realized in more American municipalities. Such cooperation, supplemented by that of the practitioner, especially in obstetrics and gynecology, can accomplish much in the course of years. But cooperation between laboratory workers also is necessary. Even the chemist, not only the pathologist, is indispensable. Without him the anatomist often is helpless. Here, for example, is an unopened, fairly normal looking abortus composed of a clean conceptus. The periamniotic fluid, to all appearances, is absolutely normal. The interior of the chorionic vesicle also appears normal. The amniotic vesicle, although much smaller than one would expect, is normal in all other respects and distended moderately with perfectly clear and absolutely normal-looking fluid; yet such a conceptus may contain not even a trace of an embryo, even if the yolk-sac still looks normal. Such specimens are rare, but they occur, and one of the things wholly inexplicable to the anatomist is not so much the absence of the embryo as the fact that its disintegration has not resulted in the least turbidity of or deposit in the amniotic fluid or the dissolution of the amnion. Even a microscopic examination of the fluid may fail to reveal any cellular content. The anatomist desires to know not merely in what respects the composition of the intra-amniotic and periamniotic fluids has been changed, but what the enzymes are that have caused the complete lysis of the embryo, from what these arise, and how they become active. These and many other questions the chemist only can answer. For this answer fresh material is indispensable, but this the neighboring practitioners or a closely associated clinic can supply. I am aware of the fact that chemists and physiologists have not neglected these questions, but at present our knowledge regarding these matters seems quite insufficient to enable one to formulate satisfactory hypotheses regarding many of the phenomena encountered in abortuses. To enable us to do this a much better localization and identification of the enzymes concerned would seem to be necessary.


That the dissolution of these early embryos, and undoubtedly also of the chorionic vesicles, is not due primarily or even very materially to phagocytic activity, is very evident, even upon cursory examination. In the presence of the intact chorionic and amniotic vesicles such a process is wholly excluded. Besides, one never sees any evidence of phagocytosis of the preserved fetal by the maternal tissues in human conceptuses, although evidences of the contrary processes are not wanting.


In considering some of the many problems of human antenatal pathology, it seems very probable that much light can be thrown upon them by comparative experimental pathology and studies in comparative gestation. A reliable knowledge of the comparative incidence of abnormalities in man and higher vertebrates alone would be of great value. The same thing would be true of a knowledge of the comparative incidence of uterine and ovarian or testicular disease and abnormalities of the uterine mucosa. Indeed, until these and other similar and related questions have received at least a partial answer, it will always remain rather venturesome to draw final conclusions regarding many things in human antenatal pathology, for the first question that always must be answered in connection with a particular specimen is that of its normality or pathogenicity.


His, Giacomini, and Mall took up this problem with especial devotion and have done much to lay the basis for the accomplishment of the task set for pathologic embryology by MUller (1847). Miiller stated that it was the task of the pathological anatomy of prenatal life to show the progressive steps leading from the slightest deviation from the normal to the most pronounced deformity. This task is only begun and progress naturally will be slow, especially in connection with early forms, until we can discriminate better between the normal and the abnormal and the pathologic.


A comparison of the clinical data relating to infection, with the microscopic findings, will show that the correspondence is extremely slight. This is not surprising, for physicians themselves often emphasize that the history probably is quite untrustworthy. Moreover, the clinical diagnosis of infection is usually based upon the presence of fever, a putrid discharge, or certain symptoms usually regarded as indicative of fever. If the clinical reports regarding infection were based upon bacteriologic or even upon histologic examination, they would undoubtedly agree better with our findings. These showed the presence of infection, as indicated by infiltration of the decidua or by abscess formation, in a large percentage of the cases in which the decidua was present, in the specimens falling into the first five groups.


The unavoidable confusion resulting from the use of the word ovum to designate the unfertilized female sex-cell, this cell when fertilized, the chorionic and amniotic vesicles with or without the embryo, and even the later product of conception in any and all stages of development, even up to birth, has prompted me to resort to additional terms. It certainly would seem best to restrict the term ovum to its comparative embryological significance and thus avoid confusion. But this restriction leaves us without a word to designate the whole product of conception. For this the word conceptus seemed available. At present the word embryo is frequently used loosely to designate conceptuses of any age. It is used still more frequently to designate merely the body of the future individual during the early stages of its development, in contradistinction to the word fetus, which usually is restricted to the later months. Hence we have need for still another term to be used in common for the embryonic disk, the embryo, or the fetus. Dr. Schultz has kindly suggested kyema, which Professor Foster suggests is preferably spelled cyema, adding that it is excellent Greek and was used in the proposed sense by Plato himself. It also has the advantage of being available for comparative embryology and of being easily adapted to meet such needs as are represented by the terms cyemetric and cyemology. Change may not imply improvement or progress, but the absence of it certainly never does. I realize fully that the use of unnecessary terms is to be avoided, but this is equally true of awkward circumlocution and misunderstanding. When one writes or says at present that no embryonic remnants were seen, it is impossible to know what is meant. Although the word embryo could by common consent be used in the proposed sense of cyema, long usage probably would make such an attempt futile for this reason alone. The use of this term and of others, presently to be suggested, does not change old meanings or old usage. It abrogates nothing save confusion.


Although the word abortion is available to designate the individual or the material aborted, it has not been the custom to use it in this inclusive sense. The word abortion, as now used, is usually restricted to the act itself. To use it in a double sense would lead to some confusion. Since blood-clot, pus, decidua, and mucosa usually are not only included with but frequently also surround the entire conceptus, I have used the word abortus to designate all the material expelled during an abortion. Only in this way can one avoid the use of such words as ovum, mole, chorion, and such expressions as the entire mass, embryonic mass, abortion mass, or (quite inaccurately) the chorionic vesicle, even when the latter is surrounded by a certain amount of decidua and blood-clot.


Since the term fetus compressus, as customarily used, refers to a twin fetus which died and was later subjected to pressure from the surviving, growing fetus during an extended period of time while it was undergoing mummification, the use of this term in Chapters III and IV requires definition. Practically all the specimens so designated in this survey are single, not twin. Besides, they have but rarely been subjected to pressure, and not a single specimen is dehydrated to the extent of being papyraceous. Rarely, when fetuses so termed have been subjected to pressure, this was the pressure of the contracted uterus subsequent to the absorption of the amniotic fluid. In many instances, however, these specimens were contained in a quantity of amniotic fluid sufficient to be protected from direct pressure of the uterus transmitted through the fetal membranes. Moreover, since all these, as well as the specimens of group 7, are macerated, and since all manner of gradations are found between the macerated swollen and the macerated wrinkled (fetus compressus) specimen, it may be preferable to restrict this term to its original usage. Much would also seem to be gained by an abandonment of such terms as decidua vera and serotina, which, although historical, convey false suggestions. The occurrence of a psuedo decidua does not seem to be at all established, and the sense in which the term vera was first used necessarily has been lost in the progress of modern embryology. The same thing applies to the term serotina. Hence, as suggested by others, it would seem preferable to speak of a parietal, a basal, and a capsular decidua, and finally relinquish the older terms.


In order to avoid possible confusion through the introduction of new terms, I have added the following diagram, which presents their relationship at a glance:

Mall Meyer1921 preface figure.jpg


In spite of the fact that some great names have long been associated with the rising subject of the pathology of human development, a routine examination of abortuses seems quite worthless to many investigators. This is natural, for, aside from the poor preservation of many of these abortuses, the conditions under which nature performs her experiments on man necessarily are uncontrolled and often also unknown. But there would seem to be no reason for rejecting any testimony which such experiments may offer, though the search be a long and a disappointing one and the conditions not standard. To regard all attempts at a study of these specimens as futile is very largely to abandon man to a cruel fate. He never can be made the subject of accurately controlled experiment or a wholly satisfying study. The rigid requirements of scientific investigation must, in the nature of things, almost always remain unfulfilled. Comparative anatomy, medicine, and pathology, as well as experiments upon animals, undoubtedly offer greater returns merely because the subject of experiment can be bred, nurtured, and sacrificed at the will and by the hand of man. But if it be conceded that in the last analysis the aim of all human effort must be directed toward the amelioration of the lot of mankind, then it would be folly to reject even the chance stalk that may spring from the grain of wheat which lay hidden in a bushel of chaff.


The conception, as well as the general plan, of this volume is that of Professor Mall himself. It was my happy experience to be invited to share in both. An unkind fate made it impossible for Professor Mall to complete his own work; for his part everyone will feel deeply grateful; for the part that might have been his, others than myself will feel an immeasurable regret.


Although the table of contents had not been prepared, the possible scope of the volume and the order of the topics had often been considered. It was the intention not only to read each other's chapters, but to discuss and revise them together. With characteristic generosity, Professor Mall suggested that, except for one chapter not contributed by either one of us (Chapter VI), we share equally in that part of the undertaking not included in the special studies. Partly in accordance with this desire, he wrote the introductory chapters in the first person plural, much against my earnest remonstrance, for my share in them is quite negligible. However, since they had been considered together they stand as he wrote them, except for a few footnotes. Unfortunately, only one of my studies was in final form before his death, but he was familiar with it, although we had not considered the paper together. Since all the remainder of my part was written subsequently, it did not seem justifiable to me to charge him with responsibility for conclusions of my own or for personal opinions which might not have commended themselves to him.


It is with the greatest satisfaction that I record in this connection his decision to mutually consider all points of difference and, if common ground could not be found, to state frankly our individual views. It was characteristic of him never to use the weight of his authority in the discussion of controverted questions or to influence anyone's conclusions. He was ever willing to leave the truth to the future. It was this attitude that made the completion of this unfinished work a very satisfying effort, even if lonely and in some respects unsatisfactory. Chapters I, II, and VIII, and all the protocols at the end of Chapter IV, below No. 1,000, fortunately had been written by him. However, in accordance with his intentions, protocols were revised and a number of them entirely rewritten. Since he himself had requested this in the case of several which we considered together, I feel that I have merely followed his desire in this matter. In the exercise of this privilege and duty of revision I have used the greatest care to preserve his descriptions as far as possible. Indeed, in the completion of this volume, it has been my constant purpose to follow his plan, to preserve his views, and to realize his intentions. Although I feel the deepest scientific interest in this work, it has also been a labor of love and devotion, and it was a great satisfaction that its continuation was made possible by the Carnegie Institution of Washington, and that its realization was furthered in every way by my friend and former colleague, Dr. George L. Streeter.


Since these studies were completed very largely during 1918 and the spring of 1919, no references are made to the recent literature in a large portion of the volume.


A. W. Meyer.



NOTE In view of the suggestions made in Science (A. W. Meyer, 1919: A suggestion from Plato, with others, vol. 49, p. 530) some of which have been incorporated in the following pages, the title of this volume demands a word of explanation. I have retained the word ova because the title had in part been decided upon. Moreover, the word is still used in this sense in current medical literature, but we are not considering ova but conceptuses. Besides, a considerable percentage of these undoubtedly are not pathologic or diseased, for surely post-mortem changes in structure, however profound, can not strictly be regarded as pathologic; and since derangement of function is made impossible by death, no matter how deformed or how infiltrated the tissues of an abortus may be with the cells of maternal origin, it can not therefore be said to be diseased. A. W. M.



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Mall FP. and Meyer AW. Studies on abortuses: a survey of pathologic ova in the Carnegie Embryological Collection. (1921) Contrib. Embryol., Carnegie Inst. Wash. Publ. 275, 12: 1-364.

In this historic 1921 pathology paper, figures and plates of abnormal embryos are not suitable for young students.

1921 Carnegie Collection - Abnormal: Preface | 1 Collection origin | 2 Care and utilization | 3 Classification | 4 Pathologic analysis | 5 Size | 6 Sex incidence | 7 Localized anomalies | 8 Hydatiform uterine | 9 Hydatiform tubal | Chapter 10 Alleged superfetation | 11 Ovarian Pregnancy | 12 Lysis and resorption | 13 Postmortem intrauterine | 14 Hofbauer cells | 15 Villi | 16 Villous nodules | 17 Syphilitic changes | 18 Aspects | Bibliography | Figures | Contribution No.56 | Contributions Series | Embryology History

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