Chapter 1 Landmarks in the History of Neurosurgery
Prehistoric Period: The Development of Trephination
In many museum and academic collections around the world are examples of the earliest form of neurosurgery—skull trephination.1–4 A number of arguments and interpretations have been advanced by scholars as to the origin and surgical reasons for this early operation—to date no satisfactory answers have been found. Issues of religion, treatment of head injuries, release of demons, and treatment of headaches have all been offered. Unfortunately, no adequate archaeological materials have surfaced to provide us with an answer. In reviewing some of the early skulls the skills of these early surgeons were quite remarkable. Many of the trephined skulls show evidence of healing, proving that these early patients survived the surgery. Figure 1.1 shows examples of two early (Peru circa AD 800) skulls that have been trephined and show evidence of premorbid bone healing. In the Americas the tumi was the most common surgical instrument used to perform a trephination and some examples of these tumis are shown in Figure 1.1. In Figure 1.2 is a fine example of a well-healed gold inlay cranioplasty done by an early South American surgeon.
FIGURE 1.2 An early cranioplasty done with a gold inlay which is well healed.
(From the Museum of Gold, Lima, Peru.)
Included in many museum and private collections are examples of terra cotta and stone figures and other carvings that clearly depicted several common neurological disorders. Commonly depicted by contemporary artisans were images of hydrocephalus, cranial deformation, spina bifida, and various forms of external injuries and scarring. We have added two examples from the Olmec and Mayan civilizations, where we see demonstrated a young adult with achondroplasia and a young adult with severe kyphoscolosis likely due to a myelomeningocele5 (Fig. 1-3).
Egyptian and Babylonian Medicine: Embryonic Period
The Egyptian period, covering some 30 successive dynasties, gave us the earliest known practicing physician—Imhotep (I-em-herep) (3000 BC). Imhotep (“he whom cometh in peace”) is considered the first medical demigod, one likely more skilled in magic and being a sage. From this period came three important medical and surgical documents that give us a contemporary view of the practice of surgery. These collections are the Ebers, Hearst, and Edwin Smith papyri, two of which are considered here.6,7
The Egyptians are well remembered for their skills developed in mummification. Historians have now shown that anatomical dissection was also performed in this period. An examination of the existing Egyptian papyri shows that the practice of medicine was based largely on magic and superstition. Therapeutic measures depended on simple principles, most of which allowed nature to provide restoration of health with little intervention. In treating skeletal injury the Egyptians realized that immobilization was important and they prescribed splints for that purpose. Their materia medica was impressive, as their substantial pharmacopeias attest.
Written some 500 years after Hammurabi (1792-1750 BC), and the oldest medical text believed to exist (including about 107 pages of hieratic writing), the Ebers papyrus is of interest for its discussion of contemporary surgical practice.7 The text discusses the removal of tumors, and recommends surgical drainage of abscesses.
The Edwin Smith papyrus, written after 1700 BC is considered to be the oldest book on surgery per se and is a papyrus scroll 15 feet in length and 1 foot in width (4.5 m by 0.3 m; Fig. 1.4).6 The text contains a total of 48 cases including those with injuries involving the spine and cranium. Each case is considered with a diagnosis followed by a formulated prognosis. Owing to the scholarly work of James Breasted this papyrus has been translated from the original Egyptian to English. The original document remains in the possession of the New York Academy of Medicine.6
FIGURE 1.4 A manuscript leaf from the Breasted translation of the Hearst papyrus discussing a head injury.
(From Breasted JH. The Edwin Smith Papyrus. Published in Facsimile and Hieroglyphic Transliteration with Translation and Commentary. Chicago: University of Chicago Press; 1930; from the author’s collection.)
Greek and Early Byzantine Period: The Origins of Neurosurgery
The earliest medical writings from this period are those attributed to Hippocrates (460-370 BC), that most celebrated of the Asclepiadae, and his schools (Fig. 1.5).8 To Hippocrates we owe the description of a number of neurological conditions, many of them resulting from battlefield and sport injuries. Hippocrates was the first to develop the concept that the location of the injury to the skull was important in any surgical decision. The vulnerability of the brain to injury was categorized from lesser to greater by location, with injury to the bregma representing a greater risk than injury to the temporal region, which in turn was more dangerous than injury to the occipital region.9
Hippocrates wrote on a number of neurological conditions. From his Aphorisms is one of the earliest descriptions of subarachnoid hemorrhage: “When persons in good health are suddenly seized with pains in the head, and straightway are laid down speechless, and breathe with stertor, they die in seven days, unless fever comes on.”10
Hippocrates provides the first written detailed use of the trephine. Insightful, he argued for trephination in brain contusions but not in depressed skull fractures (the prognosis was too grave) and cautioned that a trephination should never be performed over a skull suture because of the risk of injury to the underlying dura. Hippocrates demonstrated good surgical technique when he recommended “watering” the trephine bit while drilling to prevent overheating and injury to the dura.
Herophilus of Chalcedon (fl. 335-280 BC) was an important early neuroanatomist who came from the region of the Bosporus and later attended the schools of Alexandria. Unlike his predecessors, Herophilus dissected human bodies in addition to those of animals—more than 100 by his own account. Herophilus was among the first to develop an anatomical nomenclature and form a language of anatomy. Among his contributions was tracing the origin of nerves to the spinal cord. He then divided these nerves into motor and sensory tracts. He made the important differentiation of nerves from tendons, which were often confused at that time. In his anatomical writings are the first anatomical descriptions of the ventricles and venous sinuses of the brain. From him comes the description of confluens sinuum or torcular Herophili. The first description of the choroid plexus occurs here, so named for its resemblance to the vascular membrane of the fetus. Herophilus described in detail the fourth ventricle and noted the peculiar arrangement at its base, which he called the “calamus scriptorius” because it “resembles the groove of a pen for writing.” Among his many other contributions was his recognition of the brain as the central organ of the nervous system and the seat of intelligence, in contrast to Aristotle’s cardiocentric view.11
All was not perfect with this anatomist as Herophilus is also remembered for introducing one of the longest standing errors in anatomical physiology: the rete mirabile (Fig. 1.6),12 a structure present in artiodactyls but not in humans. This structure acts as an anastomotic network at the base of the brain. This inaccurately described structure later became dogma and important in early physiological theories of human brain function. The rete mirabile was later erroneously described in detail by Galen of Pergamon and further canonized by later Arabic and medieval scholars. Scholarship did not erase this anatomical error until the sixteenth century, when the new anatomical accounts of Andreas Vesalius and Berengario da Carpi clearly showed it did not exist in humans.
Entering the Roman era and schools of medicine, we come to Aulus Cornelius Celsus (25 BC to AD 50). Celsus was neither a physician nor a surgeon; rather, he can best be described as a medical encyclopedist who had an important influence on surgery. His writings reviewed, fairly and with moderation, the rival medical schools of his time—dogmatic, methodic, and empiric. As counsel to the emperors Tiberius and Gaius (Caligula), he was held in great esteem. His book, De re Medicina,13 is one of the earliest extant medical documents after the Hippocratic writings. His writings had an enormous influence on early physicians. So important were his writings that when printing was introduced in the fifteenth century, Celsus’ works were printed before those of Hippocrates and Galen.
Celsus made a number of interesting neurosurgical observations. De re Medicina contains an accurate description of an epidural hematoma resulting from a bleeding middle meningeal artery.8 Celsus comments that a surgeon should always operate on the side of greater pain and place the trephine where the pain is best localized. Considering the pain sensitivity of dura and its sensitivity to pressure, this has proved to be good clinical acumen. Celsus provided accurate descriptions of hydrocephalus and facial neuralgia. Celsus was aware that a fracture of the cervical spine can cause vomiting and difficulty in breathing, whereas injury of the lower spine can cause weakness or paralysis of the legs, as well as urinary retention or incontinence.
Rufus of Ephesus (fl. AD 100) lived during the reign of Trajan (AD 98-117) in the coastal city of Ephesus. Many of Rufus’ manuscripts survived and became a heavy influence on the Byzantine and medieval compilers. As a result of his great skill as a surgeon, many of his surgical writings were still being transcribed well into the sixteenth century.14 Rufus’ description of the membranes covering the brain remains a classic. Rufus clearly distinguished between the cerebrum and cerebellum, and gives a credible description of the corpus callosum. He had a good understanding of the anatomy of the ventricular system with clear details of the lateral ventricle; he also described the third and fourth ventricles, as well as the aqueduct of Sylvius. Rufus also provided early anatomical descriptions of the pineal gland and hypophysis, and his accounts of the fornix and the quadrigeminal plate are accurate and elegant. He was among the first to describe the optic chiasm and recognized that it was related to vision. The singular accuracy of Rufus’ studies must be credited to his use of dissection (mostly monkeys) in an era when the Roman schools were avoiding hands-on anatomical dissection.
His experience as a physician and his scientific studies enabled Galen to make a variety of contributions to neuroanatomy. Galen was the first to differentiate the pia mater and the dura mater. Among his contributions were descriptions of the corpus callosum, the ventricular system, the pineal and pituitary glands, and the infundibulum. Long before Alexander Monro’s Secundus (1733-1817) eighteenth century anatomical description, Galen clearly described the structure now called the foramen of Monro. He also gave an accurate description of the aqueduct of Sylvius. He performed a number of interesting anatomical experiments, such as transection of the spinal cord, leading him to describe the resultant loss of function below the level of the cut. In a classic study on the pig he sectioned the recurrent laryngeal nerve and clearly described that hoarseness was a consequence (Fig. 1.7). Galen provides the first recorded attempt at identifying and numbering the cranial nerves. He described 11 of the 12 nerves, but by combining several, he arrived at a total of only seven. He regarded the olfactory nerve as merely a prolongation of the brain and hence did not count it.15
In viewing brain function Galen offered some original concepts. He believed the brain controlled intelligence, fantasy, memory, and judgment. This was an important departure from the teaching of earlier schools, for example, Aristotle’s cardiocentric view. Galen discarded Hippocrates’ notion that the brain is only a gland and attributed to it the powers of voluntary action and sensation.
With animal experimentation Galen recognized that cervical injury can cause disturbance in arm function. In a study of spinal cord injury, Galen detailed a classic case of what is today known as Brown-Séquard syndrome—i.e., a hemiplegia with contralateral sensory loss in a subject with a hemisection of the cord.16 Galen’s description of the symptoms and signs of hydrocephalus is classic. This understanding of the disease enabled him to predict which patients with hydrocephalus had a poorer prognosis. Galen was much more liberal in the treatment of head injury than Hippocrates, arguing for more aggressive elevation of depressed skull fractures, fractures with hematomas, and comminuted fractures. Galen recommended removing the bone fragments, particularly those pressing into the brain. Galen was also more optimistic than Hippocrates about the outcome of brain injuries, commenting that “we have seen a severely wounded brain healed.”
Paul of Aegina (AD 625-690), trained in the Alexandrian school, is considered the last of the great Byzantine physicians. He was a popular writer who compiled works from both the Latin and Greek schools. His writings remained extremely popular, being consulted well into the seventeenth century. Beside his medical skills Paul was also a skilled surgeon to whom patients came from far and wide. He venerated the teachings of the ancients as tradition required, but also introduced his own techniques with good results. This author is best remembered for his classic work, The Seven Books of Paul of Aegina, within which are excellent sections on head injury and the use of the trephine.17,18 Paul classified skull fractures in several categories: fissure, incision, expression, depression, arched fracture, and, in infants, dent. In skull fractures he developed an interesting skin incision which involved two incisions intersecting one another at right angles, giving the Greek letter X. One leg of the incision incorporated the scalp wound. To provide comfort for the patient the ear was stuffed with wool so that the noise of the trephine would not cause undue distress. In offering better wound care he dressed it with a broad bandage soaked in oil of roses and wine, with care taken to avoid compressing the brain.18
The hydrocephalic affection … occurs in infants, owing to their heads being improperly squeezed by midwives during parturition, or from some other obscure cause; or from the rupture of a vessel or vessels, and the extravasated blood being converted into an inert fluid … (Paulus Aeginetes).18
An innovative personality, he designed a number of surgical instruments for neurosurgical procedures. Illustrated in his early manuscripts are a number of tools including elevators, raspatories, and bone-biters. An innovation for his trephine bits was a conical design to prevent plunging, and different biting edges were made for ease of cutting. Reviewing his wound management reveals some sophisticated insights—he used wine (helpful in antisepsis, although this concept was then unknown) and stressed that dressings should be applied with no compression to the brain. Paul of Aegina was later to have an enormous influence on Arabic medicine and in particular on Albucasis, the patriarch of Arabic/Islamic surgery.19
Arabic and Medieval Medicine: Scholarship with Intellectual Somnolence
Arabic/Islamic Scholarship
In this era of Islamic medicine we see introduced a now common medical tradition—bedside medicine with didactic teaching. Surgeons, with rare exceptions, remained in a class of low stature. One unfortunate practice was the reintroduction of the Egyptian technique of using a red-hot cautery iron, applied to a wound, to control bleeding. In some cases hot cautery was used instead of the scalpel to create surgical incisions, and this practice clearly led to a burned and subsequent poorly healed wound (Fig. 1.8).
An important Islamic scholar of this period, as reflected in his writings, was Rhazes (Abu Bakr Muhammad ibn Zakariya’ al-Razi, AD 845–925). Reviewing his works one sees clearly a scholarly physician, loyal to Hippocratic teachings, and learned in diagnosis. Although primarily a court physician and not a surgeon, he provided writings on surgical topics that remained influential through the eighteenth century.20 Rhazes was one of the first to discuss and outline the concept of cerebral concussion. Head injury, he wrote, is among the most devastating of all injuries. Reflecting some insight he advocated surgery only for penetrating injuries of the skull as the outcome was almost always fatal. Rhazes recognized that a skull fracture causes compression of the brain and thereby requires elevation to prevent lasting injury. Rhazes also understood that cranial and peripheral nerves have both a motor and sensory component. In designing a surgical scalp flap one needed to know the anatomy and pathways of the nerves so as to prevent a facial or ocular palsy.
Avicenna (Abu ‘Ali al-Husayn ibn ‘Abdallah ibn Sina, AD 980-1037), the famous Persian physician and philosopher of Baghdad, was known as the “second doctor” (the first being Aristotle). During the Middle Ages his works were translated into Latin and became dominant teachings in the major European universities until well into the eighteenth century. With the introduction of the printed book it has been commented that his Canon (Q’anun) was the second most commonly printed book after the Bible. Avicenna disseminated the Greek teachings so persuasively that their influence remains an undercurrent to this day. In his major work, Canon Medicinae (Q’anun), an encyclopedic effort founded on the writings of Galen and Hippocrates, the observations reported are mostly clinical, bearing primarily on materia medica (Fig. 1.9).21 Avicenna’s medical philosophy primarily followed the humoral theories of Hippocrates along with the biological concepts of Aristotle. Within Avicenna’s Canon (Q’anun) are a number of interesting neurological findings, such as the first accurate clinical explanation of epilepsy, for which treatment consisted of various medications and herbals along with the shock of the electric eel. He describes meningitis and recognized it was an infection and inflammation of the meninges. It appears that Avicenna might have conducted anatomical studies inasmuch as he gives a correct anatomical discussion of the vermis of the cerebellum and the “tailed nucleus,” now known as the caudate nucleus. Avicenna introduced the concept of a tracheostomy using a gold or silver tube placed into the trachea and provided a number of innovative techniques for treating spine injuries and included some devices for stabilizing the injured spine. Avicenna also had some insightful thoughts on the treatment of hydrocephalus. He recognized that external hydrocephalus (fluid between the brain and dura) could be drained with low morbidity risk. However, true internal hydrocephalus was more dangerous to treat and best left alone or treated with herbals and medications.22 The Canon (Q’anun) was clearly his greatest contribution, along with his collation and translation of Galen’s collected works, a book that remained a dominant influence until well into the eighteenth century.
A personality often overlooked in neurosurgical history was a prominent Persian/Islamic physician by the name of Haly Abbas (Abdul-Hasan Ali Ibn Abbas Al Majusi) (?AD 930-944). This writer from the Golden Age of Islamic medicine produced a work called The Perfect Book of the Art of Medicine,23 also known as the Royal Book (Fig. 1.10). Born and educated in Persia, a place he never left, it was here he produced his important writings on medicine. In his book he dedicated 110 chapters to surgical practice. A review of his work shows that his writings on spine injuries were essentially copied from the earlier Greek writers, in particular Paul of Aegina, and consisted mostly of external stabilization of spinal column injuries. Surgical intervention via a scalpel was rarely advocated. In his nineteenth discourse, Chapters 84 and 85 is clearly presented his management of depressed skull fractures. He also described the different types of fractures that can occur along with potential mechanisms of injury. He clearly appreciated that the dura should be left intact and not violated, the exception being those fractures where the skull bone had penetrated through the dural membrane, in which case these fragments needed to be removed. His technique of elevating a bone flap involved drilling a series of closely placed holes and then connecting them with a chisel. He showed some interesting consideration for the patient by advocating placing a ball of wool into the ears so as to block the sounds from the drilling. The head wound was then dressed with a wine-soaked dressing, the wine likely providing a form of antisepsis. In these chapters are also an interesting discussion about intraoperative brain swelling and edema, in which case the surgeon should look further for possible retained bone fragments and remove them. If later swelling occurred from too tight a head dressing, then it should be loosened. Unfortunately, Haly Abbas also advocated cephalic vein bleeding and inducing diarrhea for those who did not respond well; such primitive techniques were not to be abandoned until the mid-nineteenth century.
In the Islamic tradition Albucasis (Abu al-Qasim Khalaf ibn al-Abbas Al-Zahrawi, AD 936-1013) was both a great compiler as well as a serious scholar, whose writings (some 30 volumes!) were focused mainly on surgery, dietetics, and materia medica. In the introduction to his Compendium24 there is an interesting discussion of why the Islamic physician had made such little progress in surgery—he attributed this failure to a lack of anatomical study and inadequate knowledge of the classics. One unfortunate medical practice that he popularized was the frequent use of emetics as prophylaxis against disease, a debilitating medical practice that survived, as “purging,” into the nineteenth century.
The final section of the Compendium is the most important part for surgeons and includes a lengthy summary of surgical practice at that time.24–26 This work was used extensively in the schools of Salerno and Montpellier and hence was an important influence in medieval Europe. A unique feature of this text was the illustrations of surgical instruments along with descriptions of their use, which Albucasis detailed in the text. Albucasis designed many of the instruments, and some were based on those described earlier by Paul of Aegina. His design of a “nonsinking” trephine is classic (he placed a collar on the trephine to prevent plunging) and was to become the template of many later trepan/trephine designs (Fig. 1.11).
For hydrocephalus (following the teachings of Paul of Aegina, he associated the disorder with the midwife grasping the head too roughly) Albucasis recommended drainage, although he noted that the outcome was almost always fatal. He attributed these poor results to “paralysis” of the brain from relaxation. With regard to the site for drainage, Albucasis noted that the surgeon must never cut over an artery, as hemorrhage could lead to death. In the child with hydrocephalus he would “bind” the head with a tight constricting head wrap and then put the child on a “dry diet” with little fluid—in retrospect a progressive treatment plan for hydrocephalus.25,26
An important figure in the history of surgery, and one who bridged the Islamic and medieval schools, was Serefeddin Sabuncuoglu (1385-1468). Sabuncuoglu was a prominent Ottoman surgeon who lived in Amasya, a small city in the northern region of Asia Minor, part of present-day Turkey. This was a glorious period for the Ottoman Empire and Amasya was a major center of commerce, culture, and art. While working as a physician at Amasya Hospital, and at the age of 83, he wrote a medical book entitled Cerrahiyyetü’l-Haniyye [Imperial Surgery], which is considered the first colored illustrated textbook of Turkish medical literature.27–30 There are only three known copies of this original manuscript, two are in Istanbul and the third at the Bibliothèque Nationale in Paris.27 First written in 1465 the book consists of three chapters dealing with 191 topics, all dealing with surgery. Each topic consists of a single, poetical sentence in which the diagnosis, classification, and surgical technique of a particular disease are described in detail. This book is unique for this period in that virtually all the surgical procedures and illustrations were drawn in color, even though drawings of this type were prohibited in the Islamic religion (Fig. 1.12).
Medieval Europe
Constantinus Africanus (Constantine the African) (1020-1087) introduced Islamic medicine to the school of Salerno and thus to Europe (Fig. 1.13). Constantine had studied in Baghdad, where he came under the influence of the Islamic/Arabic scholars. Later, he retired to the monastery at Monte Cassino and there translated Arabic manuscripts into Latin, some scholars say rather inaccurately. Thus began a new wave of translation and transliteration of medical texts, this time from Arabic back into Latin.31 His work allows one to gauge how much medical and surgical knowledge was lost or distorted by multiple translations, particularly of anatomical works. It is also notable that Constantine reintroduced anatomical dissection with an annual dissection of a pig. Unfortunately the anatomical observations that did not match those recorded in the early classical writings were ignored! As had been the theme for the previous 400 years surgical education and practice continued to slumber.
Roger of Salerno (fl. 1170) was a surgical leader in the Salernitan tradition, the first writer on surgery in Italy. His work on surgery was to have a tremendous influence during the medieval period (Fig. 1.14). His Practica Chirurgiae offered some interesting surgical techniques.32 Roger introduced an unusual technique of checking for a tear of the dura, i.e., cerebrospinal fluid (CSF) leakage, in a patient with a skull fracture by having the patient hold his breath (Valsalva maneuver) and then watching for a CSF leak or air bubbles. A pioneer in the techniques of managing nerve injury, he argued for reanastomosis of severed nerves. During the repair he paid particular attention to alignment of the nerve fasicles. Several chapters of his text are devoted to the treatment of skull fractures. The following is a discussion of a skull fracture:
FIGURE 1.14 This early medieval manuscript illustrates a craniotomy being performed by Roger of Salerno.
(From Bodleian Library, Oxford, UK.)
When a fracture occurs it is accompanied by various wounds and contusions. If the contusion of the flesh is small but that of the bone great, the flesh should be divided by a cruciate incision down to the bone and everywhere elevated from the bone. Then a piece of light, old cloth is inserted for a day, and if there are fragments of the bone present, they are to be thoroughly removed. If the bone is unbroken on one side, it is left in place, and if necessary elevated with a flat sound (spatumile) and the bone is perforated by chipping with the spatumile so that clotted blood may be soaked up with a wad of wool and feathers. When it has consolidated, we apply lint and then, if it is necessary (but not until after the whole wound has become level with the skin), the patient may be bathed. After he leaves the bath, we apply a thin cooling plaster made of wormwood with rose water and egg.32
In reviewing the writings of Roger of Salerno we see little offered that is new in the field of anatomy. He contented himself with recapitulating earlier treatises, in particular those of Albucasis and Paul of Aegina. He strongly favored therapeutic plasters and salves; fortunately he was not a strong advocate of the application of grease to dural injuries. Citing the writings of The Bamberg Surgery,33 he advocated trephination in the treatment of epilepsy.
An unusually inventive medieval surgeon, Theodoric Borgognoni of Cervia (1205-1298) is remembered as a pioneer in the use of aseptic technique—not the “clean” aseptic technique of today but rather a method based on avoidance of “laudable pus.” He made a number of attempts to discover the ideal conditions for good wound healing; he concluded that they comprised control of bleeding, removal of contaminated or necrotic material, avoidance of dead space, and careful application of a wound dressing bathed in wine—views that are remarkably modern for the times (Fig. 1.15).
Theodoric’s surgical work, written in 1267, provides a unique view of medieval surgery.34 He argued for meticulous (almost Halstedian!) surgical techniques. The aspiring surgeon was to train under competent surgeons and be well read in the field of head injury. Interestingly, he argued that parts of the brain could be removed through a wound with little effect on the patient. He appreciated the importance of skull fractures, especially depressed ones, recognizing that they should be elevated. He believed that punctures or tears of the dura mater could lead to abscess formation and seizures. To provide comfort for the patient about to undergo surgery, he developed his own “soporific sponge,” which contained opium, mandragora, hemlock, and other ingredients. It was applied to the nostrils until the patient fell asleep. He describes results in improved comfort that were better for both patient and surgeon (Figs. 1.16, 1.17).
FIGURE 1.17 Medieval anatomist performing a dissection of the head.
(From Guido de Papia (Papaya), Anatomia circa 1325. Musèe Condé, Chantilly, France.)
William of Saliceto (1210-1277) might be considered the ablest surgeon of the thirteenth century. A professor at the University of Bologna, William of Saliceto wrote his Chirurgia,35 which many consider to be highly original, though it does carry the strong influence of Galen and Avicenna. To his credit William replaced the Arabic technique of incision by cautery with the surgical knife. He also devised techniques for nerve suture. In neurology, he recognized that the cerebrum governs voluntary motion and the cerebellum involuntary function.
Leonard of Bertapalia (1380?–1460) was a prominent figure in medieval surgery. Leonard came from a small town near Padua and established an extensive and lucrative practice there and in nearby Venice. He was among the earliest proponents of anatomical research—in fact, he gave a course of surgery in 1429 that included the dissection of an executed criminal. Leonard had a strong interest in head injury—he ended up devoting a third of his book to surgery of the nervous system.36,37 He considered the brain the most precious organ, regarding it as the source of voluntary and involuntary functions. He provided some interesting and accurate insights into the management of skull fracture. He argued that the surgeon should always avoid materials that might cause pus, always avoid the use a compressive dressing that might drive bone into the brain, and if a piece of bone pierces the brain, remove it!
Lanfranchi of Milan (c. 1250-1306), a pupil of William of Saliceto, continued his teacher’s practice of using a knife instead of cautery. In his Cyrurgia Parva he pioneered the use of suture for wound repair.38 His guidelines for performing trephination in skull fractures and “release of irritation” of dura are classic. He even developed a technique of esophageal intubation for surgery, a technique not commonly practiced until the late nineteenth century.
Guy de Chauliac (1298-1368) was the most influential surgeon of the fourteenth and fifteenth centuries and a writer of rare learning and fine historical sense. So important to surgical practice did Guy de Chauliac’s Ars Chirurgica become, it was copied and translated into the seventeenth century, a span of nearly 400 years. Most historians consider this surgical manual to be the principal didactic surgical text of this era.39,40
Sixteenth Century: Anatomical Exploration
With the beginnings of the Renaissance profound changes began to occur in surgical practices. To resolve medical and surgical practice issues, both physicians and surgeons reintroduced basic hands-on investigative techniques. Of profound influence was the now routine practice of anatomical dissection of humans. A series of prominent figures including Leonardo da Vinci, Berengario da Carpi, Johannes Dryander, Andreas Vesalius, and others led the movement. Anatomical errors, many ensconced since the Greco-Roman era, were corrected, and a greater interest in surgery developed. This radically inventive period and its personalities laid the foundations of modern neuroanatomy and neurosurgery.
Leonardo da Vinci (1452-1519) was the quintessential Renaissance man. Multitalented, recognized as an artist, an anatomist, and a scientist, Leonardo went to the dissection table so as to better understand surface anatomy and its bearing on his artistic creations. On the basis of these studies he founded iconographic and physiological anatomy.41–43 Leonardo, being a well-read man, was familiar with the writings of Galen, Avicenna, Mondino, and others. From his knowledge of these writings he developed an understanding of their anatomical errors.
To Leonardo’s studies we owe a number of anatomical firsts. Leonardo provided the first crude diagrams of the cranial nerves, the optic chiasm, and the brachial and lumbar plexuses. Leonardo made the first wax casting of the ventricular system and in so doing provided the earliest accurate view of this anatomy. His wax casting technique involved removing the brain from the calvarium and injecting melted wax through the fourth ventricle. Tubes were placed in the lateral ventricles to allow air to escape. When the wax hardened he removed the brain, leaving a cast behind—simple but elegant (Fig. 1.18).
In connection with his art studies he developed the concept of “antagonism” in muscle control. His experimental studies included sectioning a digital nerve and noting that the affected finger no longer had sensation, even when placed in a fire. Leonardo had great plans for publishing a stupendous opus on anatomy, which was to be issued in 20 volumes. The work did not appear owing to the early death of his collaborator, Marcantonio della Tore, who died in 1509.44 From 1519, the year of Leonardo’s death, until the middle of the sixteenth century, his anatomical manuscripts circulated among Italian artists through the guidance of Francesco da Melzi, Leonardo’s associate. Sometime in the mid- to late sixteenth century the anatomical manuscripts were lost, and were rediscovered only in the eighteenth century, by William Hunter.
In reviewing Paré’s surgical works,45,46 the part on the brain best reflects a contemporary surgical practice. Book X is devoted to skull fractures. Paré reintroduced the earlier technique of elevating a depressed skull fracture by using the Valsalva maneuver: “… for a breath driven forth of the chest and prohibited passage forth, swells and lifts the substance of the brain and meninges where upon the frothing humidity and sanies sweat forth.”36 This maneuver also assisted in the expulsion of blood and pus (Fig. 1.19).
In 1518 a remarkable book by Giacomo Berengario da Carpi (1460-1530) appeared.47 This book came about because of Berengario’s success in treating Lorenzo de’ Medici, Duke of Urbino, who had received a serious cranial injury and survived. In a dream that occurred shortly after this episode Berengario was visited by the god Hermes Trismegistus (Thrice-Great Mercury), who encouraged him to a write a treatise on head injuries. As a result of this dream Berengario’s Tractatus appeared and was the first printed work devoted solely to treating injuries of the head. Not only are original surgical techniques discussed but also illustrations of the cranial instruments for dealing with skull fractures are provided (Fig. 1.20