12 May

Just as Copernicus  and Galileo revolutionized  ideas about  the motions of  the  earth  and  the  heavens,  Andreas   Vesalius  (1514–1564) trans- formed Western concepts of the structure  of the human  body. Vesalius’ great  treatise,  The  Fabric  of  the  Human  Body  (De  humani  corporis fabrica), appeared  in 1543, the year in which Nicolaus Copernicus (1473–1543) published  the  text  that  placed  the  sun,  rather  than  the earth,  at the center of the universe (On the Revolutions of the Heavenly Spheres). Vesalius was heir to the humanist  medical tradition that  had rediscovered  the original writings of Hippocrates and Galen.  He was a member  of the first generation  of scholars  to enjoy access to the com- plete works of Galen.  The Fabrica,  which is considered the first anato- mical treatise  based  on direct  observation of the human  body,  is still regarded as a milestone in the history of anatomy.  In honor  of its place in the history of Western medicine, in 1998, scholars began publishing a five-volume English translation of the first edition of the Fabrica.

Given the scope of his work, Vesalius can be considered a classical scholar  and  humanist,   as  well as  a  physician,  anatomist, and  artist. Unlike  Linacre  and  Caius,  however,  Vesalius  was  able  to  renounce

Andreas Vesalius, on the fabric of the human body.

the errors  of the ancients clearly and publicly. Through  his scholarship and his own observations, he came to realize that human  anatomy  must be read  from  the ‘‘book of the human  body,’’ not  from  the pages of Galen. With all due modesty, Vesalius regarded his work as the first real advance in anatomical knowledge since the time of Galen.

A horoscope  cast  by Girolamo Cardano, a  Milanese  physician, fixes the birth  of Andreas  Vesalius in Brussels, Belgium, on December 31, 1514, at 5:45 a.m. Vesalius was born into a world of physicians, phar-macists,  and  royal  patronage. His  father  was imperial  pharmacist to Charles V and often accompanied the Emperor on his travels. As a youth, Vesalius began to teach himself anatomy  by dissecting mice and other small  animals.  Although   he  studied  at  both  the  University  of  Paris and  Louvain,  institutions notable  for  their  extreme  conservatism,  his innate curiosity was not destroyed  by the benefits of higher education.

While  a  student  at  the  University  of  Paris,  Vesalius  served  as assistant   to  Jacobus   Sylvius  (1478–1555),  an  archconservative  who saw human  dissection  only  as  a  means  of  pursuing  Galenic  studies. Unfortunately, the  atmosphere in  Paris  became  so  threatening that Vesalius found it necessary to leave without a degree. In the fall of 1537, he enrolled  in the medical school of the University  of Padua,  a vener- able, but  relatively enlightened  institution. He was awarded  the M.D. in  December  1537, and  appointed lecturer-demonstrator in  anatomy and surgery. Abandoning the traditional professorial  role, Vesalius lec- tured  and  dissected simultaneously. These dissection-lectures  occupied the anatomist and his audience from morning  to night for three weeks at  a time.  To  minimize  the  problem  of putrefaction, anatomies  were scheduled for the winter term. Several bodies were used simultaneously so that  different parts could be clearly demonstrated. Anatomies  began with a study of the skeleton, and then proceeded  to the muscles, blood vessels, nerves, organs  of the abdomen  and chest, and the brain.

By 1538, Vesalius was beginning  to recognize differences between Galenic anatomy  and his own observations, but when the young anat- omist publicly challenged Galen, Sylvius denounced  his former student as ‘‘Vesanus’’ (madman), purveyor  of filth and sewage, pimp, liar, and various epithets unprintable even in our own permissive era. Vesalius in turn told his students that they could learn more at a butcher  shop than at  the  lectures  of certain  blockhead  professors.  Referring  to  the  dis- section  skills of his former  teacher,  Vesalius said that  Sylvius and  his knife were more at home at the banquet  table than the dissecting room. In  1539, Marcantonio Contarini, a  judge  in  Padua’s  criminal  court, became so interested  in Vesalius’s work that  he awarded  the bodies of executed  criminals  to  the  university  and  obligingly  set  the  time  of execution to suit the anatomist’s  convenience.

Finally, to mark his independence from Galen, Vesalius arranged  a public  dissection  lecture  in which he demonstrated over two hundred differences between the skeletons of apes and humans,  while reminding his audience  that  Galen’s  work  was based  on  the  dissection  of apes. Hostile reactions from outraged Galenists were inevitable. Vesalian anat- omists were vilified as the ‘‘Lutherans of Physic’’ on the grounds that the heresies of such medical innovators were as dangerous as Martin Luther’s

(1483–1546) effect on religion. Tired of the controversy,  Vesalius became court physician to Charles V, Holy Roman Emperor and King of Spain, to whom he dedicated the Fabrica. Soon Vesalius discovered that imperial service was almost  as unpleasant as the stormy  academic  world.

The patronage of a king, pope, or wealthy nobleman  might allow a scientist to continue  his research,  but such patrons  were often difficult and demanding  patients.  Charles  V suffered from gout,  asthma,  and a variety  of vague complaints  exacerbated  by his predilection  for quack remedies. Moreover,  kings often loaned  their physicians to other  royal courts.  Thus,  when  Henry  II  of  France  was  injured  while  jousting, Vesalius and the French surgeon Ambroise Pare´  were among the medical consultants. Using the heads of four recently decapitated criminals, Pare´ and Vesalius carried out experiments to ascertain the nature  of the inju- ries. They correctly predicted that the wound would be fatal. According to a doubtful,  but persistent tradition, Vesalius went on a pilgrimage to the Holy Land  to extricate himself from the Emperor’s  service, or as a penance for initiating a premature autopsy.  Vesalius may have used the excuse of a pilgrimage to explore the possibility of returning  to a professorship  at Padua.  Unfortunately, he died on the return  voyage.

Despite being steeped in the conservative  academic scholarship  of his time, Vesalius confronted and rejected Galen’s authority and demanded that anatomists study only the ‘‘completely trustworthy book of man.’’ Vesalius attributed his own disillusionment  with Galen to his discovery that  Galen had never dissected the human  body. However, a minor work, known as the ‘‘Bloodletting Letter,’’ suggests that practical problems  concerning  venesection  forced  Vesalius to  question  Galenic dogma. Venesection was the subject of violent controversy among sixteenth-century physicians.  No  one  suggested  abandoning bloodlet- ting; rather,  the medical humanists  attacked  what  they called corrupt Arabist   methods   and  demanded   a  return   to  the  pure  teachings  of Hippocrates and Galen.

Unfortunately, even after ‘‘purification,’’ Galen’s teachings on the venous  system remained  ambiguous.  When  Hippocratic texts  contra- dicted each other  and  Galen,  which authority could  tell the physician how to  select the site for  venesection,  how much  blood  to  take,  how rapidly  bleeding  should  proceed,  and  how  often  to  repeat  the  proce- dure? Struggling  with these questions,  Vesalius began  to  ask whether facts established  by anatomical investigation  could be used to test the validity of hypotheses. Unable to ignore the implications  of his anatom- ical studies and  clinical experience, Vesalius became increasingly  criti- cal  of  the  medical  humanists.  He  could  not  tolerate   the  way  they ignored  the  true  workings  of  the  human   body  while  they  debated ‘‘horse-feathers  and trifles.’’ The Fabric  of the Human  Body was a  revolutionary attempt   to describe the human  body as it really is without  deferring to Galen when

the  truth  could  be  learned  through  dissection.  Vesalius  also  demon- strated   how   well  anatomical  truths   could   be  conveyed   in  words and  illustrations.  About  250 woodblocks  were painstakingly prepared and  incorporation into  the  text  where their  placement  complemented and clarified matters  described in the text. Ironically, critics of Vesalian anatomy   attacked   the  Fabrica  on  the  grounds  that  the  illustrations were false and misleading and would seduce students  away from direct observation. Actually, the importance of dissection is emphasized throughout the  text  and  careful  instructions   were  given  on  the  pre- paration of bodies for dissection and the instruments  needed for precise work on specific anatomical materials.

The Fabrica was intended for serious anatomists, but Vesalius also

prepared  a shorter,  less expensive text, known  as the Epitome, so that even medical  students  could  appreciate  the  ‘‘harmony  of  the  human body.’’ The Epitome contained  eleven plates showing the bones,  mus- cles, external  parts,  nerves, veins, and  arteries,  and  pictures  of organs that  were meant  to  be traced,  cut  out,  and  assembled  by the  reader. The Vesalian texts and illustrations  were widely plagiarized and dissemi- nated, often in the form of inferior translations and abstracts  that failed to credit the originals.

In  response  to  his  critics,  Vesalius  denounced   the  ‘‘self-styled Prometheans’’  who  claimed  that  Galen  was always  right  and  argued that  the alleged errors  in his works  were proof  that  the human  body had  degenerated  since the  classical  era.  Galenists,  Vesalius  declared, could  not  distinguish  between the fourth  carpal  bone  and  a chickpea, but  they  wanted  to  destroy  his  work  just  as  their  predecessors  had destroyed  the works of Herophilus and Erasistratus. Recalling how he had once been under  Galen’s influence, Vesalius admitted  that  he used to  keep the  head  of an  ox handy  to  demonstrate the rete  mirabile, a  network  of  blood  vessels that  Galen  had  placed  at  the  base  of  the human   brain.  Unable   to  find  the  rete  mirabile  in  human   cadavers, anatomists rationalized  this inconsistency by asserting that,  in humans, the structure  disappeared  very soon after death.  When Vesalius finally came to terms  with Galen’s fallibility,  he openly declared  that  such a network  was not present  in humans.

In contrast  to his revolutionary treatment of anatomy,  Vesalius did not go much further than Galen and Aristotle in physiology and embry- ology. He gave an exhaustive  description  of the structure  of the heart, arteries, and veins, and was skeptical of the Galenic claim that the blood moved from right heart  to left heart  through  pores in the septum,  but the motion of the blood remained obscure. Thus, while Galen was chal- lenged on anatomical details,  his overall anatomical and physiological doctrines  remained  intact.  For  example, having ruled out  the presence of the rete mirabile in humans,  Vesalius had to find an alternative  site for the generation  of the animal spirits. By interpreting Galen’s various

Inferior  view of the  cerebellum

Inferior  view of the  cerebellum as  depicted in De  Humani  Corporis  Fabrica, 1543.

accounts  of the process  that  generated  them,  Vesalius concluded  that Galen thought that  only part  of this process occurred  in the rete mira- bile; the final modifications  may have involved the brain and its ventri- cles. Vesalius could,  therefore,  ascribe the function  of the nonexistent rete mirabile to the general vicinity of the cerebral arteries.

Historians generally agree that  anatomical research  has been the cornerstone of Western  medicine since the sixteenth  century.  Inspired by the new Vesalian anatomy,  physicians focused on direct observation of the body  as the only means  of generating  valid anatomical knowl- edge.  But  anatomical  knowledge  and  the  right  to  perform   human dissection also served as a means of establishing  a unique  professional identity  and  asserting  power  over  life and  death.  The  emphasis  on human  dissection as an essential aspect of medical education,  however, led  to  increasing  tension  between  the  apparently insatiable  need  for cadavers and the widespread prejudice against  human  dissection. Until recent  times, anatomists were often  forced  into  dangerous  and  illegal methods  of  obtaining  human  bodies.  As a  medical  student  in  Paris, Vesalius  fought  off  savage  dogs  while collecting  human  bones  from the Cemetery  of the Innocents.  In Louvain,  he stole the remains  of a robber  chained to the gallows and brought  the bones back into the city hidden under his coat. Grave-robbing incidents were reported  wherever Vesalius conducted  his famous  lecture-demonstrations. One ingenious group  of  medical  students  reportedly   obtained   a  corpse,  dressed  it, and walked their prize into the dissecting room as if it were just another drunken  student  being dragged  into  class. Despite  anecdotes  that  fea- ture  the  bravado   of  enterprising  anatomists, being  associated  in  the popular  mind  with  hangmen  and  grave  robbers  was humiliating  and dangerous  to  anatomists. When  anatomists were fortunate enough  to obtain cadavers, they faced grave dangers during routine dissections, because even the smallest cut could result in a fatal infection.

Long after most European nations  had made legal provisions  for anatomical studies,  body  snatching  provided  the bulk  of the teaching material  for gross anatomy  in Great  Britain,  Canada, and  the United States.  Anatomists too  timid  to obtain  cadavers  themselves turned  to entrepreneurs known  as  ‘‘Resurrectionists’’  or  ‘‘Sack-Em-Up  Men,’’ who  procured   bodies  by  grave  robbing,   extortion,  and  murder.   In England,  under  the Murder  Act of George  II, the bodies of criminals considered  vile  enough  to  be  worthy  of  death  and  dissection  were awarded  to  the  Royal  College  of  Surgeons  as  a  ‘‘peculiar  mark  of Infamy  added  to  the  Punishment.’’  When  England’s  1832 Anatomy Act allowed the state to give the unclaimed bodies of paupers to medical schools, poverty became virtually as deeply stigmatized as criminality. It is interesting to note that the Visible Human  Project began with the use of a 39-year-old criminal executed by lethal injection in 1993. The body was  frozen,  sectioned,  and  transformed into  the  first  fully  digitized human   being.  Today,   the  National  Library   of  Medicine’s  Visible Human Project provides invaluable radiological scans and digitalized photographs of cross-sections of a male and a female cadaver.

American  physicians  also  attempted to  establish  a  professional identity through  anatomical knowledge. This created an infamous black market  for cadavers.  Following  the example set in England,  physicians successfully lobbied for laws that  allocated  paupers’  bodies to medical schools. But scandalous  stories of body snatching  and dissection-room pranks  continued  to inflame the public. Advocates of improved medical and surgical training were obliged to remind legislators and laymen that

if doctors  did not practice on cadavers, they would have to learn the art at  the  expense  of  their  patients.  The  Latin  motto  used  by  Medical Examiners  and Pathology  Departments around the world—‘‘Hic locus est  ubi mors gaudet  succurrere  vitae’’  (This  is the  place  where  death delights   to   help   the   living)—stresses   the   insights   physicians   and researchers  gain through  human  dissection.

By the  beginning  of  the  twentieth  century,  gross  anatomy   had become an essential part  of the curriculum  at every American  medical school. By the end of that century, the hours devoted to formal anatomy training had sharply declined and the shortage of instructors had become more significant than the problem of obtaining  cadavers. Many medical educators  argued that computerized  scans and three-dimensional repre- sentations   of  the  human   body  provided   better  teaching  tools  than traditional dissections, although  standardizing models ignores the variability  of human  anatomy.  Others  insist that  human  dissection  is an  essential  aspect  of  conveying  the  lesson  of  human  mortality  and the meaning  of being a doctor.  The French  anatomist Marie  Franc¸ois Xavier Bichat (1771–1802) stressed the importance of conducting autop- sies. ‘‘Open up a few corpses,’’ he wrote, ‘‘you will dissipate at once the darkness that observation alone could not dissipate.’’

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