Uncovering the Relationship Between Anatomy and Disease

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Uncovering the Relationship Between Anatomy and Disease

Overview

The knowledge of basic human structure is known as the science of anatomy. The term anatomy comes from the Greek word anatome, which literally means dissection and often encompasses many other disciplines, such as physiology (the study of body function). While it is one of the oldest sciences and wrought with rich tradition, it is also one of the most disappointing from the standpoint of its development before the seventeenth century. As an example, it was known how the earth moved around the sun nearly one hundred years before it was known that blood moved through the body. One aspect of this slow growth in the knowledge base was the belief in the sanctity of the human body. Most dissections were performed on animals up until the sixteenth century because it was believed in most cultures that the human body must be preserved or protected after death, and that dissection was a defilement.

Background

The study of anatomy dates to antiquity. Herophilus of Chalcedon (330?-260? b.c.), who made detailed studies of dissections of the human body in the third century b.c., is often considered to be the founder of anatomy. His detailed descriptions of both the structure of the human body and how it related to function served as a template of study for his successors, the greatest of which was Galen of Pergamum (a.d. 129-216?).

Galen was the first person to tie disease and anatomy together. While Hippocrates (460?-377? b.c.) is often considered the most important early figure in the area of disease and medicine, he made no recognized contributions to anatomy. As the physician for Roman emperor Marcus Aurelius in the second century a.d., Galen was considered the foremost authority on anatomy and disease for the next 1,300 years. He made many important discoveries while exclusively studying animals. For example, he demonstrated that urine was formed in the kidneys and that damaging the spinal cord caused paralysis below the injury on the same side. He also made many mistakes, but so great was his influence that these went unquestioned for centuries. Such complacency and blind acceptance of received wisdom is often detrimental to the progression of science, and such was the case for the science of anatomy, which stagnated until the sixteenth century.

In 1543 Andreas Vesalius (1514-1564) published an account of human anatomy that proved to be the most significant publication in this area since Galen. This event is considered to be the point at which the science of anatomy enters the modern era. His work is significant because he published his own observations that were often is opposition to Galen. Thus, Vesalius opened the door for the progression of anatomy. Because he provided accurate descriptions of normal structures, it was then possible to begin to correlate disease with changes in structure. While very skillful and methodical, Vesalius was at a disadvantage because he performed his studies without the aid of any optical devices (gross anatomy), so he had to rely on his unaided observations, which could make out details no smaller than 0.019 in (0.48 mm). It was not until the microscope was invented that detailed study of cellular structures could be made.

William Harvey (1578-1657) made some of the most important advances in the history of medicine when in 1628 he published his idea that blood circulated through the body. This piece of information is so vital to our concept of modern medicine that it would not exist without it. As an example, it would be impossible to understand heart disease, which currently accounts for about one-third of all deaths in modern society. Harvey made other significant contributions, but he too was hampered by a lack of technology and could not prove the existence of capillaries, which was central to his idea of blood circulation. That missing link was provided by the Italian scholar Marcello Malpighi (1628-1694), who was the first to use a microscope in conjunction with the study of human anatomy.

Malpighi is considered the father of histology (the study of cells and tissues), and he provided basic information that allowed structure to be related to disease. In fact, modern diseases are often diagnosed through changes in cells and tissues that can only be evaluated histologically. With basic anatomy and physiology concepts now in hand, the stage was set for more advanced study of the relationship between structural changes in the body and disease.

Although the correlation between clinical symptoms and pathological changes was not made until the first half of the nineteenth century, the first textbook of morbid anatomy (pathology) was published in 1761 by an Italian scholar Giovanni Battista Morgagni (1682-1771). This book, The Seats and Causes of Disease, was the first publication to link specific diseases with individual organs. He was the first to demonstrate the necessity of basing diagnosis, prognosis, and treatment on a comprehensive knowledge of anatomical conditions. Morgagni's investigations were directed chiefly toward the structure of diseased tissue, both during life and postmortem, in contrast to the normal anatomical structures. While this type of work was not originated by Morgagni, he did publish the largest, most accurate, and best illustrated work yet seen. From this time on, morbid anatomy became a recognized branch of the medical science.

Morgagni performed 640 dissections for his famous treatise. He was careful to link symptoms with structural changes induced by disease in the human body. For this reason, he is known as the father of pathology (the study of disease). He popularized the idea that observation was an important medical tool.

The Hunter family had a significant legacy on the development of thought regarding anatomy, disease, and treatment during the eighteenth century. William Hunter (1718-1783), his brother John Hunter (1728-1793), and their nephew Matthew Baillie (1761-1823) made important contributions during their lifetimes.

John Hunter has been referred to as the father of modern English anatomy. He was a renowned surgeon and researcher, especially in the areas of obstetrics, and was the first to discover that the mother and fetus have separate blood circulations. His brother William was responsible for making surgery a science. He incorporated scientific inquiry, physiology, and pathology into surgery, making it much more valuable than it had been previously. John Hunter was so influential that the history of surgical technique is often divided into two distinct categories, pre- and post-Hunter. Hunter was also influential because he had a famous pupil, Edward Jenner (1749-1823), who introduced the smallpox vaccination and is considered the founder of preventive medicine. Matthew Baillie was a Scottish pathologist whose Morbid Anatomy of Some of the Most Important Parts of the Human Body (1793) was the first publication in English on pathology as a separate subject and furthered the systematic study of pathology.

Impact

The clinical correlations between disease and anatomy paved the way for modern medicine to become much more effective in treating ailments. Ancient medical practices centered on relieving demonic possession, not investigating an organic cause for the disease. The medicine man and his modern forms (physicians) are one of the oldest professions on record, but lack of knowledge regarding the pathological basis for disease has plagued societies with poor and even unethical treatments. As an example, the oldest surgical procedure on record involves opening the skull with a sharp stone to let the evil spirit that is causing the disease out. If the patient died, it was blamed on the spirit, not the procedure. The evolution of modern treatment techniques have their roots firmly implanted in the initial research involving morbid anatomy.

Prior to Morgagni, disease was thought to be a general condition. That is, there was not much consideration regarding the cause. Morgagni's influence forever changed how doctors dealt with disease. It was Morgagni who first correlated the symptoms of the disease during life with the pathological changes in organs found at autopsy. He demonstrated that through a careful examination of the deceased body, one could begin to attribute outward changes that occurred with disease with specific organs in the body. With his careful and thoughtful work, doctors could think in specific terms such as heart or liver disease. Proper treatment for a specific disease would not be available for most diseases unless the exact cause was known. Diseases could now be thought of in scientific terms and defined by the differences between normal and abnormal conditions of the body. With the technology available at that time, the only way of finding that out was through the careful examination and study of people who had passed away.

Much of the work that was performed in the eighteenth century provided the impetus for future study and helped to set up strict guidelines regarding the thoroughness of scientific inquiry in the area of pathology. It paved the road for subsequent researchers such as Rudolf Virchow (1821-1902), the father of modern pathology. In the nineteenth century Virchow showed that the structural changes in disease happen not in the organ as a whole, but rather in the cells for that organ.

JAMES J. HOFFMANN

DR. JOHN LETTSOM AND EIGHTEENTH-CENTURY MEDICAL PRACTICE

The goal of eighteenth-century medical intervention was to restore the balance of the four "humors" of the body. Physicians usually attempted to accomplish this task by ridding the body of corrupt humors through bleeding, purging, or sweating, as in this poem by Dr. John Lettsom: "I John Lettsom / Blister, purge and sweats 'em. / If after that they choose to die, / I, John, lets 'em."

LOIS N. MAGNER

Science and Its Times: Understanding the Social Significance of Scientific Discovery