(also morbid anatomy), a scientific discipline that studies the morphological basis of pathological processes in man and animals and the morphological aspects of pathogenesis. Pathological anatomy is the most important branch of pathology. It is concerned with both macroscopic changes, which are visible to the naked eye, and microscopic changes, which require use of a microscope and which constitute the subject matter of pathological histology. A distinction is made between general and special pathological anatomy. The former is concerned with the morphology of standard pathological processes (circulatory, disturbances, metabolic disorders, inflammation, and tumors). The latter is concerned with the morphology of individual diseases.

The principal method in human pathological anatomy is autopsy, or postmortem examination. If performed with the clinical data in mind, an autopsy affords a retrospective clinicomorphological analysis of the disease and points to possible shortcomings of the diagnosis and treatment. Organs and tissues that are removed during surgical operations as well as biopsy specimens are subjected to pathologicoanatomical examination to determine the exact nature of the pathological process and the efficacy of surgical intervention. Owing to advances in medical technique and surgery, almost all organs and tissues are now accessible to such examination. The following types of biopsy, whose use is becoming increasingly more widespread, are commonly performed: aspiration biopsy; surgical biopsy, in which a slice of tissue is excised; and punch biopsy, in which a specimen is obtained by puncturing an organ.

For living patients, pathological anatomy relies on analysis of biopsy specimens. Experiments that simulate human diseases are also extensively used. Among the methods used in pathological anatomy are many forms of microscopy, for example, light, phase-contrast, fluorescence, polarizing, and electron microscopy. Cytological, histological, histochemical, histoimmuno-chemical, autoradiographic, and morphometric methods are also relied on, both singly and in combination. Thus, it is possible to trace pathological processes on the organic, tissual, cellular, and ultrastructural levels and to correlate morphological changes with functional changes. These methods and goals bring modern pathological anatomy closer to pathophysiology.

Pathological anatomy barely progressed until the 18th century, when religious and folk prejudices against examining the dead began to dissipate. Its evolution into an independent discipline was brought about by the classic studies of G. Morgagni in the second half of the 18th century and those of M. F. X. Bichat in the early 19th century. Atlases and handbooks of pathological anatomy appeared in the mid-19th century, notably, J. Cruveilhier’s in France, K. Rokitansky’s in Austria, and R. Virchow’s in Germany. During this period, departments of pathological anatomy were established in many European universities, and schools of pathologicoanatomical thought came into existence, especially under the influence of E. Ziegler, F. Marchand, and E. Albrecht in Germany and M. Letulle in France.

In Russia, cadavers were dissected as early as the time of Peter I, in the teaching hospitals that he had founded. The first department of pathological anatomy was established in the medical faculty of Moscow University in 1849. The founder of the Moscow school of pathologicoanatomists was A. I. Polunin; among the school’s representatives were M. N. Nikiforov, A. I. Abrikosov, I. V. Davydovskii, M. A. Skvortsov, and A. I. Strukov. A department of pathological anatomy was established in 1859 in the Medical and Surgical Academy in St. Petersburg under the directorship of M. M. Rudnev; among its representatives were N. P. Ivanovskii, G. V. Shor, V. G. Garshin, and N. N. Anichkov. Similar departments were founded in other cities, including Kazan, Kharkov, and Kiev.

In the 20th century, pathological anatomy has benefited from advances in biology, chemistry, and physics. It also has drawn closer to the related theoretical and practical medical disciplines and thus broadened its applicability. Modern pathological anatomy is not only concerned with the morbid anatomy of the patient but also with the physical basis for the earliest stages of functional disturbances. The science can uncover this basis even in disorders that were previously regarded as “purely functional.” Together with pathophysiology, pathological anatomy deals with the fundamental problems encountered in general and special pathology.

Practical instruction in pathological anatomy makes use of prosection, which is done in pathologicoanatomical departments of hospitals. The chief of the department is a pathologicoanatomist called the prosector. The health system in several countries, including the USSR, has a special pathologicoanatomical branch that organizes prosection demonstrations and takes part in sponsoring clinicoanatomical conferences. In Russia, the first societies of pathologicoanatomists were founded in St. Petersburg (1909) and Moscow (1914). The All-Union Society of Pathologicoanatomists was founded in 1947, and in 1969 it joined the International Council of Societies of Pathology, which had been established in 1950. In some countries, institutes of pathology function as national and international research centers, for example, the Institute of Human Morphology of the Academy of Medical Sciences of the USSR and the institutes of pathology in Heidelberg and Berlin.

Periodicals that deal with pathological anatomy are published in many countries, for example, Arkhiv patologii (USSR, since 1934), Virchow’s Archiv (West Berlin, since 1847), Annales de l’anatomie pathologique (Paris, since 1924), American Journal of Pathology (Boston, since 1925), Archives of Pathology (Chicago, since 1926), and Archivio italiano di anatomia e istologia patologica (Milan, since 1930).

Pathological anatomy is taught to medical students. In the USSR, unlike in other countries, instruction in the pathological anatomy of specific organs has been replaced by instruction in the pathological anatomy of specific diseases. Advanced training is provided in pathologicoanatomical departments of institutes for advanced training of physicians.

In veterinary medicine. Veterinary pathological anatomy has developed as a result of advances in human pathological anatomy and has generated extensive data for general, comparative, and experimental pathology. In addition, it is useful for the study of the nature and pathogenesis of animal diseases, in diagnosis, in forensic veterinary medicine, and for veterinary inspection of meat and meat products. The pathological anatomy of livestock, poultry, and fur-bearing animals is more advanced than that which relates to fish, reptiles, wild animals, and useful insects, for example, bees.

Veterinary pathological anatomy developed rapidly in the second half of the 19th century. Among the prominent foreign scientists active in the field were T. Kitt, E. lost, and K. Nieberle in Germany, V. Babes in Rumania, and F. Hutyra and J. Marek in Hungary.

The greatest Russian contribution to veterinary pathological anatomy was made by I. I. Ravich, A. A. Raevskii, and N. N. Mari, who wrote the first Russian textbooks and monographs. The leading Soviet scientists in the field are professors K. G. Bol’ and N. D. Ball and their many students, including V. Z. Cherniak, B. K. Bol’, and B. G. Ivanov. Soviet veterinary pathologicoanatomists have studied many aspects of the general pathology and pathogenesis of infectious, invasive, and noninfectious animal diseases that are economically harmful in stock raising. These diseases include anthrax, tuberculosis, glanders, rabies, cattle plague, swine plague, and infectious equine anemia.

In the USSR, departments of veterinary pathological anatomy and pathologicoanatomical sections exist in all veterinary research institutes and schools, in diagnostic laboratories, and in many meat-packing plants. The specialized literature is extensive, and many scientific handbooks and textbooks are in print.

In 1960, Soviet specialists in veterinary pathological anatomy joined the veterinary section of the All-Union Society of Pathologicoanatomists, which holds congresses regularly and publishes Trudy.