Andreas Vesalius
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| Andreas Vesalius |
Andreas Vesalius is the Latinized form of the Dutch Andries van Wesel, a common practice among European scholars in his time. His name is also given as Andrea Vesalius, André Vésale, Andrea Vesalio, Andreas Vesal, André Vesalio and Andre Vesalepo.
Early life and education
Vesalius was born as Andries van Wesel to father Anders van Wesel and mother Isabel Crabbe on 31 December 1514, in Brussels, which was then part of the Habsburg Netherlands. His great grandfather, Jan van Wesel, probably born in Wesel, received his medical degree from the University of Pavia and taught medicine in 1428 at the then newly founded University of Leuven. His grandfather, Everard van Wesel, was the Royal Physician of Emperor Maximilian, while his father, Anders van Wesel, went on to serve as apothecary to Maximilian, and later valet de chambre to his successor Charles V. Anders encouraged his son to continue in the family tradition, and enrolled him in the Brethren of the Common Life in Brussels to learn Greek and Latin prior to learning medicine, according to standards of the era.
In 1528 Vesalius entered the University of Leuven (Pedagogium Castrense) taking arts, but when his father was appointed as the Valet de Chambre in 1532, he decided to pursue a career in the military at the University of Paris, where he moved to in 1533. There he studied the theories of Galen under the auspices of Jacques Dubois (Jacobus Sylvius) and Jean Fernel. It was during this time that he developed his interest in anatomy, and was often found examining heads at the Cemetery of the Innocents.
Vesalius was forced to leave Paris in 1537 owing to the opening of hostilities between the Holy Roman Empire and France, and returned to Leuven. Here he completed his studies under Johann Winter von Andernach and graduated the next year. His thesis, Paraphrasis in nonum librum Rhazae medici arabis clariss. ad regem Almansorum de affectuum singularum corporis partium curatione, was a commentary on the ninth book of Rhazes. He remained at Leuven only briefly before leaving after a dispute with his professor. After settling briefly in Venice in 1536, he moved to the University of Padua (Universitas artistarum) to study for his doctorate, which he received in 1537.
Medical career
The day of his graduation he was immediately offered the chair of surgery and anatomy (explicator chirurgiae) at Padua. He also guest-lectured at Bologna and Pisa. Prior to arriving in Padua, Vesalius traveled through Italy, and assisted the future Pope Paul IV and Ignatius of Loyola healing those afflicted by Hansen’s disease (leprosy). In Venice, he met his illustrator Johan van Calcar, a student of Titian. It was with van Calcar that Vesalius published his first anatomical text, Tabulae Sex, in 1538.Previously these topics had been taught primarily from reading classical texts, mainly Galen, followed by an animal dissection by a barber–surgeon whose work was directed by the lecturer. No attempt was made actually to check Galen's claims; these were considered unassailable. Vesalius, in contrast, performed dissection as the primary teaching tool, handling the actual work himself and urging students to perform dissection themselves. Hands-on direct observation was considered the only reliable resource, a huge break with medieval practice.
He created detailed illustrations of anatomy for students in the form of six large woodcut anatomical posters. When he found that some of these were being widely copied, he published them all in 1538 under the title Tabulae anatomicae sex. He followed this in 1539 with an updated version of Guinter's anatomical handbook, Institutiones anatomicae.
In 1539 he also published his Venesection letter, on bloodletting. This was a popular treatment for almost any illness, but there was some debate about where to take the blood from. The classical Greek procedure, advocated by Galen, was to let blood from a site near the location of the illness. However, the Muslim and medieval practice was to draw a smaller amount of blood from a distant location. Vesalius' pamphlet generally supported Galen's view, but with qualifications that rejected the infiltration of Galen.
In 1541, while in Bologna, Vesalius uncovered the fact that all of Galen's research had been based upon animal rather than human anatomy; since dissection had been banned in ancient Rome, Galen had dissected Barbary macaques instead, and argued that they would be anatomically similar to humans. He also contributed to the new Giunta edition of Galen's collected works and began writing his own anatomical text. Until Vesalius pointed out Galen's substitution of animal for human anatomy, it had gone unnoticed and had long been the basis of studying human anatomy. However, some people still chose to follow Galen and resented Vesalius for calling attention to such glaring mistakes.
Galen assumed that arteries carried the purest blood to higher organs such as the brain and lungs from the left ventricle of the heart, while veins carried blood to the lesser organs such as the stomach from the right ventricle. In order that this theory could be correct, some sort of holes were needed to interconnect the ventricles, and so in the spirit of Galen's time, he claimed to have found them, adjusting the facts to suit his theory. So paramount was the authority of Galen that for 1400 years a succession of anatomists had claimed to find these holes until finally Vesalius admitted he could not find them. Nonetheless, he did not venture to dispute Galen on the distribution of blood, and so imagined that it diffused through the unbroken partition between the ventricles.
Other famous examples of Vesalius disproving Galen's assertions were his discoveries that the lower jaw (mandible) was only one bone, not two (which Galen had assumed from animal dissection) and that humans lack the rete mirabile, a network of blood vessels at the base of the brain that is found in sheep and other ungulates.
In 1543, Vesalius conducted a public dissection of the body of Jakob Karrer von Gebweiler, a notorious felon from the city of Basel, Switzerland. He assembled the bones and finally donated the skeleton to the University of Basel. This preparation ("The Basel Skeleton") is Vesalius' only well-preserved skeletal preparation today, and is also the world's oldest surviving anatomical preparation. It is still displayed at the Anatomical Museum of the University of Basel.
In the same year Vesalius took residence in Basel to help Johannes Oporinus publish the seven-volume De humani corporis fabrica (On the fabric of the human body), a groundbreaking work of human anatomy that he dedicated to Charles V. Many believe it was illustrated by Titian's pupil Jan Stephen van Calcar, but evidence is lacking, and it is unlikely that a single artist created all 273 illustrations in a period of time so short. At about the same time he published an abridged edition for students, Andrea Vesalii suorum de humani corporis fabrica librorum epitome, and dedicated it to Philip II of Spain, son of the Emperor.
Though Vesalius' work was not the first such work based on actual autopsy, nor even the first work of this era, the production values, highly detailed and intricate plates, and the likelihood that the artists who produced it were clearly present in person at the dissections made it into an instant classic. Pirated editions were available almost immediately, an event Vesalius acknowledged in a printer's note would happen. Vesalius was 28 years old when the first edition of Fabrica was published.
Imperial physician and death
The Holy Roman Emperor, Charles V, who was an important patron for Vesalius
Soon after publication, Vesalius was invited as Imperial physician to the court of Emperor Charles V. He informed the Venetian Senate that he was leaving his post in Padua, which prompted Duke Cosimo I de' Medici to invite him to move to the expanding university in Pisa, which he refused. Vesalius took up a position in the court, where he had to deal with the other physicians mocking him as being a barber.
Over the next eleven years Vesalius traveled with the court, treating injuries from battle or tournaments, performing postmortems, administering medications, and writing private letters addressing specific medical questions. During these years he also wrote the Epistle on the China root, a short text on the properties of a medical plant whose efficacy he doubted, as well as defense of his anatomical findings. This elicited a new round of attacks on his work that called for him to be punished by the emperor. In 1551, Charles V commissioned an inquiry in Salamanca to investigate the religious implications of his methods. Vesalius' work was cleared by the board, but the attacks continued. Four years later one of his main detractors and one-time professors Jacobus Sylvius, published an article that claimed that the human body itself had changed since Galen had studied it.
After the abdication of Emperor Charles V he continued at court in great favor with his son Philip II, who rewarded him with a pension for life by making him a count palatine. In 1555 he published a revised edition of De humani corporis fabrica.
In 1564 Vesalius went on a pilgrimage to the Holy Land, some said, after being accused of dissecting a living body. He sailed with the Venetian fleet under James Malatesta via Cyprus. When he reached Jerusalem, he received a message from the Venetian senate requesting him again to accept the Paduan professorship, which had become vacant by the death of his friend and pupil Fallopius.
After struggling for many days with the adverse winds in the Ionian Sea, he was wrecked on the island of Zakynthos.Here he soon died in such debt that a benefactor kindly paid for his funeral. At the time of his death he was scarcely fifty years of age. He was buried somewhere in the island of Korfu.
For many years it was assumed that Vesalius's pilgrimage was due to pressures of the Inquisition. Today this is generally considered to be without foundation and is dismissed by modern biographers. It appears the story was spread by Hubert Languet, a diplomat under Emperor Charles V and then under the Prince of Orange, who claimed in 1565 that Vesalius had performed an autopsy on an aristocrat in Spain when the heart was still beating, leading to the Inquisition condemning him to death. The story went on to claim that Philip II had the sentence commuted to a pilgrimage. The story re-surfaced several times over the next few years, living on until recent times.
Scientific findings
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's theories and writings which he had put in his anatomy books. 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 rib fewer 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 illustrations that accompany the text in De fabrica, which would become known as the "muscle men". He 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 was his greatest contribution to the complex and modern medicine. In his dissections of the heart, Vesalius became convinced that Galen's claims of a porous Interventricular septum were false. This fact was previously described by Michael Servetus, fellow of Vesalius, but never reached the public, for it was written down in the "Manuscript of Paris",in 1546, and just published later in his Christianismi Restitutio (1553), an heretic book for the Inquisition. Vesalius published in the second edition that the septum was indeed waterproof, 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 Estienne's findings on the valves of the hepatic veins, but he described the azygos vein, and discovered the canal which passes into the fetus between the umbilical vein and vena cava.
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 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. He correspondingly believed that nerves themselves do not originate from the heart, but that they stemmed from the brain.
Upon studying the optic nerve, Vesalius came to the conclusion that nerves were not hollow.
Abdominal organs
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 excretions from the kidneys then travelled through the ureters to the bladder.
He described the omentum, and its connections with the stomach, the spleen and the colon 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 of 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
Through his work with muscles, Vesalius believed that a criterion for muscles was their voluntary motion. On this claim, he deduced that the heart was not a true muscle due to its obvious involuntary nature of its motion.
He identified two chambers and two atria. The right atrium was considered a continuation of the inferior and superior venae cavae and the left atrium was considered a continuation of the pulmonary vein.
Interestingly, he also addressed the controversial issue of the heart being the centre of the soul. He wished to avoid making any conclusions due to the possible conflict with contemporary religious beliefs.
Base of the brain, showing optic chiasma, cerebellum, olfactory bulbs, etc.
Against Galen's theory and many beliefs he also discovered that there was no hole in the septum or heart.
Miscellaneous
Vesalius disproved Galen's assertion that men have more teeth than women.
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 structure 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.
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
The influence of Vesalius' plates representing the partial dissections of the human figure posing in a landscape setting is apparent in the anatomical plates prepared by the Baroque painter Pietro da Cortona (1596–1669), who executed anatomical plates with figures in dramatic poses, most with architectural or landscape backdrops.
During the 20th century, the American artist, Jacob Lawrence created his Vesalius Suite based on the anatomical drawings of Andreas Vesalius.
“De Fabrica received a mixed reception when it first appeared; strict Galenists deplored its attacks on their master, while other anatomists, particularly in Italy, praised it as an important contribution - the reaction that was ultimately to carry the day,” Katharine Park concludes her Commentary in the 1998 De Fabrica.
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