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Andreas Vesalius (Brussels, December 31, 1514 - Zante, October 15, 1564) was an anatomist, physician, and author of one of the most influential books on human anatomy, De humani corporis fabrica (On the Workings of the Human Body). Vesalius is often referred to as the founder of modern human anatomy.
Biography Vesalius was born into a family long associated with the medical care of the imperial dynasty, most notably being his father who was the pharmacist for Charles V of Germany. From an early age, Vesalius showed an inclination to follow in the family tradition through his dissection of dead birds and mice. He studied at the University of Leuven from 1530 until 1533, when he began his studies at the University of Paris under Jacobus Sylvius and Johann Guinter. At the outbreak of the war between France and the Holy Roman Empire in 1536, Vesalius returned home to complete his studies at the University of Leuven, where he received his medical degree in 1537. In the autumn of 1537, Vesalius enrolled in the medical school of the University of Padua, and received his doctorate of medicine shortly thereafter. Upon his graduation, he was immediately offered the chair of Surgery and Anatomy (explicator chirurgiae) at Padua, where he began giving public lectures. His innovative lectures and course plans were unique for two reasons. First, he performed his own dissections rather than reading aloud while a demonstrator did the dissection and second, because he used drawings to aide his teaching. These drawings became an integral part in his teaching, and later in his published works. Soon thereafter, Vesalius became interested in the validity of Galen's findings, and began his study on human anatomy and his major work, De humani corporis fabrica. In 1539, a Paduan judge became interested in Vesalius' work, and made bodies of executed criminals available for dissection. His collection of detailed anatomical diagrams grew, many of which were produced by commissioned artists in the area and were of better quality than previous diagrams. His diagrams became known as the first accurate set of diagrams to be produced. In 1540, Vesalius went to Bologna where he presented his anatomical findings and criticized Galen for his methods of studying the human anatomy. Between 1539 and 1542, Vesalius compiled his findings, a majority of which were in contradiction to Galen's work, in his masterpiece, De fabrica, and employed talented artists to provide illustrations of the human body, an important feature of his book. Soon after the publication of De fabrica, Vesalius was invited to become the imperial physician to the court of Emperor Charles V, where over the next twelve years, he traveled with the court, treated injuries from battles and tournaments, and performed surgeries as well as postmortems. He also wrote private letters that addressed specific medical questions. After the abdication of Charles, he continued working for the court under Charles's son, Philip II, who rewarded Vesalius with a life pension. On a trip back from Jerusalem in 1564, Vesalius died in a shipwreck off the coast of Greece. Publications The first of his publications came in 1538 when he published the drawings he had been using in his lectures at Padua. Produced in Venice, Tabulae anatomicae sex (Six Anatomical Tables) consisted of six large anatomical plates depicting the portal, caval, arterial and nervous systems. These figures were distinctly novel both in their size and in their detailed identification of the parts through an elaborately categorized anatomical terminology in Greek, Latin, Arabic, and Hebrew. Also in 1538, Vesalius wrote Epistola docens venam axillarem dextri cubiti in dolore laterali secundam (exact translation not found) which demonstrated a revived venesection, a classical procedure in which blood was drawn near the site of the ailment. He sought to locate the precise site for venesection in pleurisy within the framework of the classical method. The real significance of the book lay in Vesalius' attempt to support his arguments by the location and continuity of the venous system from his observations rather than appeal to earlier published works. With this novel approach to the problem of venesection, Vesalius posed the then striking hypothesis that anatomical dissection might be used to test speculation. From his work on Epistola, Vesalius moved onto dissect more and more cadavers. The discoveries he made only led him to realize that there were significant contradictions between Galen's text and his own observations of the human form. He spent the next few years working on a composition to highlight his dissections. In an effort to produce what has come to be considered one of the greatest books of the sixteenth century, Vesalius set out to hire the best draftsmen he could find to make the illustrations and the finest Venetian block cutters to produce them. In 1543, Vesalius had Johannes Oporinus publish the seven-volume De humani corporis fabrica (On the Workings of the Human Body), which he monitored carefully, to the extent that he traveled to Basel to oversee the production of his masterpiece. It was a groundbreaking work of human anatomy which he dedicated to Charles V and which most believe was illustrated by Titian's pupil Jan Stephen van Calcar. His book marked the overthrow of traditional Galenic anatomy and acted as a building block for the advancement of modern observational science. De fabrica stands as a major scientific achievement because the illustrations and text set a standard for clarity and accuracy especially in the first two books, which focus mainly on osteology and myology. The same year that Vesalius published De fabrica, he created a condensed version of the same book for his students and laymen. This version, entitled De humani corporis fabrica librorum epitome (Abridgement of the Workings of the Human Body) or more commonly known as Epitome, had a stronger focus on illustrations than text, so as to help readers easily understand his findings. The actual text of Epitome was an abridged form of his work in De fabrica, and the organization of the two books were wuite varied. Later, in 1555, Vesalius produced a second edition De fabrica, which was significantly altered in style and the contents were once again rearranged. He added to and corrected his earlier edition by including his observations made over the thirteen years since De fabrica was originally published. Skeletal System • Vesalius believed the skeletal system to be the framework of the human body. It was in this opening chapter, or book, of ''De fabrica'' that Vesalius made several of his strongest claims against Galen. In his extensive study of the skull, Vesalius claimed that the mandible consisted of one bone, whereas Galen had thought it was two separate bones. He accurately described the vestibule in the interior of the temporal bone of the skull. • In Galen’s observation of the ape, he had discovered that their sternum consisted of seven parts which he assumed held true for humans. Vesalius discovered that the human sternum only consisted of three parts. • He also disproved the common belief that men had one fewer rib than women and noted that fibula and tibia bones of the leg were indeed larger than the humerus bone of the arm, unlike Galen’s original findings. Muscular System • Vesalius’ most impressive contribution to the study of the muscular system may be the incredible illustrations that accompany the text in De fabrica, which would become known as the "muscle men". He beautifully describes the source and position of each muscle of the body as well as providing information on their respective operations. Vascular and Circulatory Systems • Vesalius’ work on the vascular and circulatory systems may be his most significant and complex contribution to modern medicine. Upon his dissections of the heart, Vesalius became confident that Galen’s claims of a porous intraventricular septum were false. It wasn’t until the second edition of De fabrica that he stated that the septum was indeed impermeable, thus discovering (and naming) the mitral valve to explain the blood flow. • Vesalius believed that the cardiac systole is synchronous with the arterial pulse. • He not only verified the observation of Etienne on the valves of the hepatic veins, but he described the vena azygos, and discovered the canal which passes in the fetus between the umbilical vein and the vena cava, since named ductus venosus. • He also noted the interior mesenteric and the hemorrhoidal veins. Nervous System • Vesalius defined a nerve as the mode of transmitting sensation and motion and thus refuted his contemporaries’ claims that ligaments, tendons and aponeuroses were three types of nerve units. He believed that nerves do not originate from the heart, as was the Aristotelian belief, but that nerves stemmed from the brain. • Upon studying the optic nerve, Vesalius came to the conclusion that nerves were not hollow. Abdominal Organs • Although Vesalius accepted Galen’s inaccurate claim that the liver was the locale of blood production, he would not accept that the vena cava stems from the liver. He also disproved Galen’s belief that the liver consisted of five lobes, and stated that is, instead, one lobe. • In De fabrica, he corrected an earlier claim he made in Tabulae about the right kidney being set higher than the left. Vesalius claimed that the kidneys were not a filter device for the urine to pass through but rather that the kidneys serve to filter blood as well and that the excrement then traveled through the ureters to the bladder. • He described the omentum, and its connections with the stomach, the spleen and the colon and gave the first correct views of the structure of the pylorus. • He also observed the small size of the caecal appendix in man and gave the first good account of the mediastinum and pleura. • Vesalius admitted that due to a lack in pregnant cadavers, he was unable to come to a significant understanding of the reproductive organs. However, he did find that the uterus had been falsely identified as having two distinct sections. Heart
Brain • Vesalius’ most significant contribution to the study of the brain was his trademark illustrations in which he depicts the corpus callosum, the thalamus, the caudate nucleus, the lenticular nucleus, the globus pallidus, the putamen pulvinar, and the cerebral peducles for the first time. Miscellaneous • Vesalius introduced the notion of induction of the extraction of empyema through surgical means. • Due to his impressive study of the human skull and the variations of its features he is said to have been responsible for the launch of the study of physical anthropology. • Vesalius always encouraged his students to check their findings, and even his own findings, so that they could better understand the workings of the human body • In addition to his continual efforts to study anatomy he also worked on medicinal remedies and came to such conclusions as treating syphilis with chinaroot. • Vesalius believed that the brain and the nervous system are center of the mind and emotion in contrast to the common Aristotelian belief that the heart was the center of the body. • Claimed medicine was arranged into three parts: drugs, diet, and 'the use of hands' - mainly suggesting surgery and the knowledge of anatomy and physiology through dissection. • Vesalius was a supporter of 'parallel dissections' in which an animal cadaver and a human cadaver are dissected simultaneously in order to demonstrate the anatomical differences and thus uncover Galenic errors. Scientific and Historical Impact Modern medicine is forever in debt to the efforts put forth by Vesalius and his ethic to provide the most accurate form of the human body. The manner in which Vesalius tended to his work could arguably be thought of as more significant than the work itself. By overthrowing the Galenic tradition and relying on his own observations, Vesalius created a new scientific method. His desire to strive for the truth is most evident through his ability to correct his own claims and to continually reshape his thoughts on the human body. Through his attention to detail, he was able to provide clear descriptions and unprecedented anatomical drawings that set a new standard for future medical books. See also | ||||||||||
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