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A. External Examination. General.

B. Internal Examination.

The organs may be inspected and opened in the body without removing them; but when weights and measures are desired they should be removed and sectioned on the table. When the spinal cord is removed posteriorly it should be done at the beginning of the autopsy, for the sake of convenience and cleanliness. If the thorax and abdomen are examined first there is a loss of solidity and resistance, making the posterior opening of the spinal canal more difficult. The head may be opened while the cadaver is face downward and the brain removed with cord attached. If the cord is examined anteriorly this should be done at the close of the autopsy after the thorax and abdomen are completely cleaned out. The head should be opened before the heart and great vessels are cut in order to avoid bleeding the sinuses and pial veins. It should be kept elevated until the heart has been examined to avoid bleeding the latter through the jugulars. The abdomen is opened before the thorax so that the position of the abdominal organs and the height of the diaphragm can be correctly noted. A complete survey of the peritoneal cavity should be made at once before the appearances are changed through the loss of blood or other fluids, or through drying or handling. The size of the liver should be estimated before the heart is cut out, inasmuch as the loss of blood through the cut inferior vena cava may reduce its size as much as one-half. The pleural cavities should be examined before its vessels are cut, as the escape of blood may alter the appearances of the pleurae. The heart is opened before the lungs are removed, so that its blood-content may be judged. The section of the neck organs is conveniently carried out according to anatomic relationships, beginning with the tongue. In the abdomen the spleen is removed first because it is the most easily gotten out of the way. The intestines up to the duodenum may be taken next, or the adrenals and kidneys, followed then by the gastro-intestinal tract, pancreas and liver. When necessary the kidneys may be removed in connection with the pelvic organs. In the case of extensive growth of neoplasms, marked inflammatory processes, adhesions, malformations, anomalies, etc., the order must be changed to meet in the best way the demands of the situation. Such changes in the order must always be mentioned in the protocol. It is a great mistake to begin the autopsy with a local examination of a supposed fatal lesion, except in the cases of wounds, particularly in medicolegal cases, in which a most careful and minute description of the wound is necessary.

In my judgment it is extremely bad practice to examine first that part of the body which the clinician believes to be chiefly affected. Still worse is it to limit the autopsy to such a regional examination. Imperfect and subjective conclusions will be avoided if the regular order is followed and each organ examined objectively. In all cases a complete autopsy should be made if permission can be obtained, and the permit for an autopsy should be regarded as one for a complete examination unless definite exceptions have been made. The examination of any organ or part should never be neglected. Many prosectors habitually omit the section of the neck-organs, intestines and genital tract when there is nothing to attract especially their attention to these parts. The examination of the spinal cord, orbits, nasal tract, ears, joints and bones may be omitted in the ordinary autopsy in the absence of especial considerations directing attention thereto; all other parts should be systematically examined. The pathologist must always maintain an unprejudiced state of mind toward the clinical diagnosis--rather a doubting mind than a disposition to accept the suggestions of the clinical opinions. The best cure for subjectivity is the complete performance of the autopsy in regular routine order, and the dictation of the protocol at the autopsy table during the operation.

THE PROTOCOL.

The protocol must be purely objective and exact. All appearances should be so carefully described that from the protocol itself a diagnosis may be formulated. Conclusions and diagnoses have no place in the protocol until the final summing up. It is better to describe the appearance of organs than to class them as "normal" or "negative," "nothing notable," etc. The only excuse for the employment of such phrases is a lack of time for the dictation of a proper protocol, but the scientific value of the autopsy is thereby impaired. As the complete description of the normal appearances would require too much time and lessen that available for the pathologic examination, the prosector should describe briefly the chief characteristics of the normal organ, any variation in any one of these characteristics being sufficient evidence that the organ had suffered pathologic change. The description of the normal organ, however, usually offers the greatest difficulty to the beginner, and so much time may be spent upon this that the pathologic changes are slighted. However, the relatively small number of points constituting the criterion for the normal organ may be learned by experience and by the study of autopsy-protocols made by experts. The latter study is also necessary for the acquisition of the extensive protocol terminology that has been developed. A knowledge of this terminology lightens greatly the difficulties of the protocol; but its misuse leads to confusion and incorrect interpretations.

It is not a good plan to write up the protocol after the autopsy has been finished. It should be dictated during the progress of the autopsy. Only in this way can an accurate and purely objective description be obtained. The use of simple, terse English and the proper employment of autopsy terminology are also chief factors in the production of a good protocol.

The importance of following a definitely-outlined routine of procedure is very evident in the case of protocol-making. The general order of the autopsy should be followed strictly in the protocol; and all deviations from the usual method noted and described. Aside from this general order, each organ or part as it is examined should be systematically described according to the following scheme:

The judgment of the color of the tissues and organs of the human body is extremely difficult because of the fact that only rarely is a pure simple color seen. Ordinarily a combination of colors is present, and the analysis of these is often not easy. If the organ is held before the eyes at a distance of about a yard an impression of a single color-unity may be obtained, but when brought nearer to the eyes the surface presents a variegated, mottled, speckled or streaked effect of many colors, sometimes running the entire range of the spectrum. The colors most frequently seen in the body are yellow, red and brown in all possible combinations and shades. Blue, gray, slate, black, green and purple are also common in combination with these three or with one another. The analysis of the color is concerned, first with the color proper of the parenchyma, secondly with the color of the blood and the blood-content, thirdly with the color of some pathologic substance contained in the tissue, as blood- or bile-pigment, carbon, melanin, etc. In describing color-combinations use the predominant color last; as, for example, a reddish-yellow-brown means that the predominant color is brown with more yellow in it than red. Innumerable combinations of these three colors exist . The macroscopic color will not be apparent in microscopic preparations except when due to a true pigment.

The term discolored is applied to dirty, cloudy colors, particularly gray or greenish, as in gangrene. Spotted, mottled, streaked, variegated, etc., have the same application in the autopsy-protocol that they have elsewhere. The judgment of the color of an organ should be made twice: as seen through the capsule or external covering, and again on the cut surface of the organ. In the latter case the transparency, translucency or opacity of the surface should be noted with the color. Normally translucent structures become opaque as the result of inflammatory thickening, parenchymatous degenerations, leukocyte infiltrations, tubercles, postmortem digestion, etc. An increase in translucence may be due to oedema, hydropic degeneration, amyloid, mucoid and colloid degenerations, liquefaction necrosis, anaemia, atrophy, loss of pigment, etc. .

THE EXTERNAL EXAMINATION.

The presence of petechiae or ecchymoses in the skin is characteristic of all the forms of essential purpura ; such skin hemorrhages occur also as the result of trauma, congenital haemophilia, in the course of many infections , in many intoxications , also in severe anaemia, pernicious anaemia, leukaemia, sarcoma, carcinoma, acute yellow atrophy of the liver, hysteria, vicarious menstruation, reflex hemorrhages, stigmatization, etc. The number, size, color and location of all cutaneous hemorrhages should be recorded.

THE EXAMINATION OF THE SPINAL CORD.

The cadaver is placed face downwards, with medium-sized blocks beneath the cervical and lumbar regions, the arms being folded underneath the body. With the cartilage-knife an incision is then made through the skin and subcutaneous tissues in the median line, over the spinous processes, beginning above at the occipital prominence and ending at the lower border of the sacrum. The skin and subcutaneous tissues are then dissected back by bold slashing strokes for a distance of a hand's breadth on both sides of the spine, thus laying bare the muscles of the neck and back. The muscles may be stripped back with the skin, but the heavy flaps thus formed are very likely to fall back and cover the seat of operation. Chain retractors may be used to hold the skin flaps back, particularly in the case of a very fat individual, but usually the separate stripping of the skin and muscles is sufficient. To remove the muscles the cartilage knife is set close against the spinous processes of the uppermost vertebrae and a deep cut made on each side of the spine throughout its entire length, severing the vertebral attachments of all muscles and tendons. About four finger-breadths outside of these cuts there should now be made from above downwards on both sides another deep cut through the muscles parallel with the first two incisions. The bundles of tendons and muscles between these parallel cuts on both sides of the spine are then separated from the bones as cleanly as possible, beginning either above or at the sacral end, severing the muscle-mass at the end at which the separation begins, but leaving it attached at the other end, where it is laid over the side of the body out of the way, and replaced after the examination of the cord is completed; or the two bundles of muscle may be cut off at both ends and disposed of without further trouble. Portions of tissue clinging to the vertebrae should then be scraped or cut away with the chisel or knife.

When the vertebrae are bared the next step is the removal by saw, bone-forceps or chisel of the posterior bony wall of the spinal canal in such a manner as to expose the cord and permit of its removal without causing any damage to it, either from the instruments or from fragments of broken bone. A single-bladed saw with curved ends may be used to saw through the laminae on both sides of the spinous processes; or even the small bone-saw may be used for this purpose. The blade of the saw should be held obliquely against the spinous processes with the sawing edge directed outward so as to cut the laminae close to the medial borders of the ascending and descending transverse processes. The sawing is complete when the spinous processes become movable. The straight-edged chisel may be used to cut any adhesions left after sawing, and the bone-forceps may be used to cut the atlas and axis. When the laminae have been cut through on both sides of the spinal column for its entire length, including the sacrum, the posterior ligament between the atlas and occiput is cut with the cartilage knife; and the strip of bone and ligaments loosened by sawing is torn off from above downward by grasping it in the upper cervical region with a pair of bone-nippers and jerking it off forcibly downward toward the sacrum, thus exposing the spinal canal. It may be taken off in the opposite direction by cutting the ligament between the last lumbar vertebra and the sacrum and stripping upward.

Another easy and convenient way of opening the spinal canal posteriorly is the cutting of the laminae by means of special bone-forceps designed for this purpose. The cutting-edges may engage the laminae from without or the lower blade may be introduced into the canal as a blunt probe, while the upper blade cuts down upon it through the side of the arch. Such bone-forceps should be very strong and have long handles to give sufficient purchase, as a good deal of force is necessary to cut through the laminae. With a good instrument the canal can be opened in this way in about 10-15 minutes. It requires much less skill than is needed for good and quick work with the Brunetti chisels, and for that reason is recommended, as is also the use of Luer's rhachiotome, for the general practitioner.

In the case of marked curvatures of the spine it may be impossible to use either rhachiotome or Brunetti chisels. The straight single chisel and small saw can be used on the concave and convex sides of the curvature respectively. In children and young adults the canal can be easily opened with the bone-forceps.

After the removal of the posterior wall of the spinal canal the peridural adipose tissue and the dural sac are exposed in the canal. The cord may now be removed with dural sac intact, and when the cord is soft this should be done, but in so doing the spinal fluid is likely to be lost; and, as it is very important to obtain a knowledge of the amount and character of this fluid, care should be taken to preserve it. With the block placed under the cervical region to keep the cervical and dorsal vertebrae higher than the lumbar the dural sac may be opened in the median line from above downward. The cervical dura is grasped with a pair of forceps and lifted so that a cut can be made in it with the small bent, probe-pointed shears. The blunt probe-point is then introduced into the subdural space and the dura cut in the median line downward toward the sacrum. With care the arachnoideal sac with its fluid may be preserved intact. What fluid there is in the subdural space will collect in the lumbar region and may be secured while the lumbar dura is cut. The fluid in the subarachnoideal space will likewise collect in the lower portion of the cord, and it is best at this stage of the operation to introduce a sterile pipette through the delicate arachnoid and draw up the fluid, preserving it for bacteriologic and microscopic examination.

When it is desired to remove a part of the spinal column for preservation as a specimen, the intervertebral cartilages and the cord above and below the portion to be removed are cut through with the knife, and the ribs severed with a chisel, while the adherent soft parts are cut away. The saw or chisel is then used to complete the disarticulation if necessary and the loosened portion is removed. The entire spine may be removed, if desired; and may be bisected with a band-saw. A stick of wood may be put in the place of the spine and covered with plaster-of-Paris.

After the cord and dura have been removed the inner surface of the canal should be examined. The character of the cut surface of the vertebral bodies is also noted, and the bones examined for pathologic conditions.

Anteroposterior diameter of cervical cord 0.9 cm. Anteroposterior diameter of dorsal cord 0.8 cm. Anteroposterior diameter of lumbar cord 0.9 cm. Transverse diameter of cervical cord 1.4 cm. Transverse diameter of dorsal cord 1.0 cm. Transverse diameter of lumbar cord 1.2 cm.

Adhesions to inner meninges, consistence , color , translucency , moisture, color and blood-content of cut surface, relation of white and gray matter, symmetry of parts, size of central canal, presence of cavities, areas of softening , hemorrhages, congestion, anaemia, oedema, gumma, tubercle, tumors, parasites, etc. The normal consistence of the lower portion of the cord is usually somewhat firmer than that of the upper part. The "butterfly-figure" should stand out distinctly on the freshly-cut surface; the outlines between the white and gray matters should be sharp, and the gray matter should be grayish-red in color. Normally the white matter tends to rise above the gray. Inasmuch as the cord is often injured accidentally during its removal it is important to distinguish such artefacts from pathologic softenings. This can be easily done by taking a small portion of the doubtful area and examining in the fresh state under the microscope. In true softening numbers of "fat-granule" cells and also capillary walls showing fat-degeneration are seen.

The pathologic lesions of the cord easily recognized by the naked-eye are areas of sclerosis or gray degeneration, yellow degeneration, hemorrhage, anaemia, oedema, congestion, tabes dorsalis, amyotrophic lateral sclerosis, acute poliomyelitis, syringomyelia, ascending and descending degenerations, glioma, gumma, tubercle, certain malformations, neoplasms and parasites. Other important pathologic conditions are: Malformations , atrophy, myelitis, sclerosis, effects of trauma, syphilis and intoxications, infections, tuberculosis, etc. Primary tumors are: Glioma, gliosarcoma, gliomyxoma, sarcoma , neuroepithelioma, neuroma, diffuse gliosis, etc. All are rare with the exception of the gliomata. Metastatic carcinoma and sarcoma are relatively rare. Cysticercus and echinococcus are rare.

The thickness, color, consistence and translucence of the spinal ganglia should be noted. Atrophic nerves are smaller, more gray and more translucent.

THE EXAMINATION OF THE HEAD.

The scalp is next loosened anteriorly by means of the hands, using the tip of the cartilage-knife occasionally to nick the fascia and thus facilitate the working forward of the anterior flap until it has been loosened as far as the supraorbital ridges anteriorly and down to the level of the beginning and ending of the incision made across the vertex. When sufficiently loosened the anterior scalp-flap is turned over the face, and stretched over the chin, where it will remain, out of the way, and with both face and hair protected. The posterior flap of the scalp is then worked back to the same level at the sides and to the lower border of the occipital protuberance posteriorly. It is then turned under between the back of the neck and the wooden block. In stripping the scalp the greatest care should be taken not to cut or tear off the periosteum. Scars, tumors, adhesions, traumatic lesions, etc., in the scalp should be carefully worked out and described as the flaps are loosened. The convex margin of the fascia of the temporal muscles is now cut with the point of the cartilage-knife and the muscles are stripped down on both sides to the level of the folded-over scalp-flaps, where they are either left hanging down out of the way or are cut off and laid aside. If they cannot be easily stripped down, they may be scraped off with the chisel. Some prosectors remove them at the same time with the scalp, but this is usually not well done. The skull now should be bare, except for the periosteum, down to the level of a line passing just above the upper margin of the orbits anteriorly, at the sides just above the aural opening, and posteriorly just below the occipital protuberance.

The periosteum is next removed over the entire cranial surface by means of the chisel, bone-scraper or dull knife. In medicolegal cases particularly it is of the greatest importance that the periosteum be removed in this way and the surface of the skull-cap carefully examined. In ordinary cases the periosteum is often left attached to the skull-cap when the external examination shows no pathologic conditions to be present.

After the examination of the periosteum and external surface of the cranium the skull-cap is removed by sawing in such a way that a space large enough for the convenient and safe removal of the brain is afforded. This may be done in several ways. A circular incision may be made through the skull around its entire circumference just above the level of the folded-over flaps of scalp. The left hand should be protected by a folded towel. The head is held firmly in the left hand and turned slightly toward the left. The saw-cut is then begun anteriorly about 1/2 cm. above the supraorbital margins, and continued around to the right, while the head is turned more and more to the left. The ear should be held down out of the way by an assistant. The saw-cut is continued then at the same level to the posterior median line just below the level of the occipital protuberance. The saw is then removed and the head turned as far as possible to the right; the saw-cut is then continued around the left side from the posterior median line until the beginning of the cut in front is reached and the circular incision is complete.

Another method of sawing the skull-cap is to saw in two planes, forming an angle just behind and below the ear . The anterior cut is made above the hair-line of the forehead and carried down at the sides to meet just below and behind the ear the posterior semicircular cut made at this level. A modification of this method is to make the anterior and posterior cuts join at a sharper angle in front of the ears. Both of these methods have for their object the prevention of disfigurement of the forehead. When the circular method is used a depression or ridge is often seen in the forehead, after the restoration of the body, due to the slipping of the skull-cap after it has been replaced. Such an accident may happen even when the bones are wired together, unless great care has been taken in wiring.

A more satisfactory way of opening the skull, and one that makes slipping of the skull-cap after restoration practically impossible, is the method used by the writer, and illustrated in Fig. 26. The scalp-incision and the folding back of the flaps are carried out as described above. The right half of the anterior flap of the scalp is then taken in the left hand and used to control the position of the head, the latter being turned to the left as far as possible. An oblique saw-cut is then made on the right side in a line extending from the posterior margin of the site of the posterior fontanel, over the right parietal eminence toward the right mastoid prominence. The sawing begins on the greatest convexity and is continued upward a slight distance beyond the median line, and downward far enough to cross the level of the connecting horizontal cut to be made later at a level just above the aural canal. The left half of the posterior scalp-flap is now taken into the left hand and used to steady the head while it is turned over to the right as far as possible. A similar oblique cut is then made on the left side, crossing the one made on the right, in the median line, behind the site of the posterior fontanel, and extending down across the left parietal eminence in the direction of the left mastoid prominence. While the head is still held by the left half of the posterior scalp-flap a horizontal saw-cut is begun on the left side, just above the aural canal, intersecting the oblique cut posteriorly and continued around to the front at a level just above the supraorbital ridges. When the frontal region is reached the head is steadied by holding the left half of the anterior portion of the scalp-flap. When the horizontal cut reaches the right temple the right half of the anterior flap is taken in the hand, and the head turned to the left while the cut is carried around the right temporal region to intersect the right oblique cut. When the skull-cap is removed there is formed an interlocking joint which under ordinary conditions holds the restored skull-cap firmly without wiring and without the formation of a ridge or crease on the brow, since the bone cannot slip. It is best, however, in the event of the shipment of a cadaver by rail to wire the bones to prevent any forcible dislodgement.

Whatever method is used the greatest care should be taken to saw the skull-cap without injuring the brain. The difference in thickness of different portions of the cranium must be borne in mind. Sight, sound and "the feel" are taken as guides. The outer and inner tables, the diplo?, and the dura have an entirely different resistance and give a different sound. The saw-dust of the outer table is white, that of the diplo? red, that of the inner table white. As soon as the saw strikes the dura a peculiar "rustling" or "scraping" sound is heard, and this should be taken as the warning to stop sawing. On curved surfaces it is best to begin sawing on the greatest convexity and to continue until the saw is through and then to extend the cut from this point. The sawing should be done lightly and quickly, without too strong pressure. Set the saw carefully at first, to avoid slipping. The small bone-saw is usually used for this operation; saws attached to electric or dental engines are sometimes employed. Care should be taken to bring the beginning and ending of the saw-cut into the same plane; and the oblique cuts should be symmetrical.

As soon as the sawing is completed, no matter what method is used, the T-chisel or skull-opener is used to spring off the skull-cap. The chisel-blade is inserted into the saw-cut in the right frontal region, and turned sideways with a quick, powerful movement of the right hand. Any portions of the inner table not completely sawed through are thus broken, and the dura is loosened sufficiently from the inner table to allow the prosector to introduce the fingers of the right hand beneath the skull-cap in the frontal region and to hold down the dura while the fingers of the left hand inserted into the frontal saw-cut pull the skull-cap backward with a powerful tug, completely separating it from the dura, unless the dura is adherent throughout, as is the case in very young children, old people, and in certain pathologic conditions. In the latter case it may be necessary to cut the dura along the line of the horizontal saw-cut and to remove it with the skull-cap, cutting the falx as the skull-cap is lifted. In young children the dura must always be removed with the skull-cap. In the case of pathologic adhesions an attempt should be made first to separate them from the lamina vitrea by cutting them with a knife or chisel-blade inserted through the saw-cut. As the adhesions are severed the skull-cap is lifted gradually backward. Too much force should not be used in jerking off the skull-cap, else the brain may be damaged. Whenever possible the dura should be left intact, as a better judgment is thereby obtained of the intradural pressure, and there is less danger of losing the contents of the subdural space.

Some prosectors use hammer and chisel to remove the skull-cap. This is a bad method, particularly so in the case of medicolegal autopsies, as artificial fractures of the skull may thus be produced. It is safest never to use a hammer in the opening of the skull.

The skull-cap is examined as soon as taken off. If the periosteum was not previously removed it is now scraped off, and the skull-cap examined against the light. After its complete examination the operator proceeds to the removal of the brain.

The left hemisphere is now turned still more to the left, and with the brain-knife a broad, smooth cut is made through it downward and outward at an angle of 45?, reaching nearly to the cortical surface, in a line connecting the cut through the frontal lobe with that through the occipital and passing along the outer borders of the corpus striatum. The left hemisphere is thus separated in the form of a prism-shaped mass having a convex under surface. The severed hemisphere falls back by the force of its own weight and the flat cut-surface of the cerebrum is then bisected by a cut made at right angles to it, from before backward, and extending nearly to the cortical surface. In the case of both of these large incisions of the hemisphere the severed parts are left connected by a small portion of cortical tissue and the pia. The knife should be perfectly dry and clean while making these cuts, and the cut surfaces should not be touched with the fingers or knife-blade, or wet with water, until they have been carefully inspected. Other straight parallel cuts may be made through the brain substance toward the cortex, the severed portions being left connected by the pia so as to permit future orientation.

The right lateral ventricle is now opened. The four fingers of the left hand are placed outside and beneath the right hemisphere with the thumb on the median surface, gently raising the hemisphere toward the left, taking care to see that the corpus callosum is not pulled over to the right of the median line. The knife is held in the right hand beneath the left one. The right ventricle is then opened in the same way as the left, beginning in the middle of the corpus callosum near to the gyrus cinguli, and opening first the anterior horn and then the posterior. The operation is somewhat more difficult on the right side than it is on the left, owing to the lack of tension in the cut corpus callosum, so that greater care must be taken to avoid injuring the floor of the ventricle. After the opening of the ventricle the right hemisphere is cut by long parallel incisions made in the same way as on the left side.

Some prosectors in opening the right ventricle prefer to turn the board around so that the frontal lobe points to the operator. The right hemisphere is then held in the left hand and the right ventricle opened just as if it were the left ventricle, except that the posterior horn is opened before the anterior. The method given above can be just as easily learned, and time is saved by not turning the board around twice, as is necessary in the latter case.

After the right ventricle has been opened the corpus callosum and fornix are raised by the thumb and index-finger of the left hand, putting the septum pellucidum on the stretch. The narrow brain-knife is then introduced through the interventricular foramen from the right, its blade flat, with cutting edge directed forward and upward, and the fornix and the corpus callosum are cut anteriorly, exposing the cavity of the septum pellucidum. To expose the third ventricle, the corpus callosum, septum pellucidum and fornix are then lifted up and laid back from the velum chorioides. The tela chorioidea is then, with the chorioid plexus of the third ventricle, pulled backward from over the pineal body and the corpora quadrigemina, care being taken not to tear away the pineal body. The veins entering the tela from the great ganglia are cut with the point of the knife. The right descending posterior pillar or crus of the fornix is then lifted with the thumb and index-finger of the left hand, the brain-knife on the flat side with cutting edge to the right is introduced beneath it, and the crus is cut toward the right. The corpus callosum, fornix and tela are then turned over to the left , fully exposing the pineal body and the corpora quadrigemina.

The cerebellum and medulla are now supported by the index-finger of the left hand placed beneath the latter; while the brain-knife is held nearly horizontally in the right, and a deep sagittal cut is made into the vermis exactly in the median line so as to make a small opening into the fourth ventricle. The point of the knife with cutting edge upward is then introduced into this opening and the incision through the vermis increased anteriorly and posteriorly until the two cerebellar hemispheres fall apart and the fourth ventricle is wholly opened. The point of the knife, with cutting edge upward may then be introduced into the posterior opening of the aqueduct and the latter opened to the third ventricle, the pineal body being removed before the cut through the roof of the aqueduct is made. In the Virchow method the corpora quadrigemina and the vermiform portion of the cerebellum are sectioned in the median line by a cut opening up both aqueduct and the fourth ventricle. Other prosectors open the aqueduct from the third ventricle toward the fourth. The left cerebellar hemisphere is now cut through in the line of the middle branch of the arbor vitae, exposing the dentate nucleus. Each half of the hemisphere is again bisected by a cut made at right angles to the surfaces exposed by the first cut. The right cerebellar hemisphere is then similarly sectioned.

The section of the brain now shows all of the ventricles and their relations, as well as the condition of a large part of cerebral and cerebellar brain-substance. All cut portions are connected with each other and it is possible to fix the entire brain as it now stands and later find no difficulty in topographic orientation. There still remains, however, the demonstration of the conditions in the basal ganglia, pons, medulla, etc. These structures are best shown by transverse cuts made across the entire brain as it lies after the opening of the ventricles. The hemispheres may be cut singly, but it is better to cut both of them at the same time, using a dry blade and drawing the knife from left to right, making identical cuts on the two sides, that the histologic features may be compared. The transverse cuts may be made in the same region as recommended in the method of Pitres , or they may be made closer together. As the cuts are made the sections are separated from each other by the knife-blade and the cut surfaces examined. After the cerebrum has been cut transversely in this way the peduncles, pons, medulla and cervical cord are elevated on the index-finger of the left hand and also sectioned transversely and the cut surfaces examined. If the index-finger be placed beneath the medulla parallel with its long axis, and medulla and pons raised up the cerebellar lobes fall to the side out of the way. All transverse cuts are made from left to right and so deep that only a small portion of brain-tissue, or the basal meninges hold the parts together for future orientation. The brain is now completely sectioned, with all parts preserved and capable of being restored to their normal relations. The parts may be re-assembled and the entire brain put into the fixing fluid, when it is desirable to save the entire organ for microscopic study.

After the third cut the fingers of the left hand are taken out of the central fissure. The sections of brain as they are cut are left lying in their order with the posterior face of the cut upward. The same incisions are then made in the other hemisphere and the two series of sections compared. The cerebellum, pons and medulla are then examined as described above.

The brain-mantle on both sides is now separated from the brain-stem at the basal portion of its frontal end. The knife, held nearly horizontal, is introduced into the fissure between the posterior border of the orbital convolutions and the anterior border of the lamina perforata anterior; and a cut is made slightly downward, not quite parallel with the orbital surface, about 3 cm. anteriorly in the medulla of the orbital convolutions, around the under surface of the head of the corpus striatum. The temporal ends of the brain-mantle are then cut through, the knife moving externally between the temporal lobe and the island, inside between the descending horn of the lateral ventricle and the optic tract. As soon as the inner cut has been extended beyond the outer corpus geniculatum on both sides, the knife is turned downward at right angles, in a curving stroke, to cut through the junction of the occipital lobes with the stem, internally along the portion of the corpus striatum adjacent to the optic thalamus, externally between the junction of the first temporal convolution with the operculum on one side, and the posterior end of the island on the other. When this has been done on both sides the blade of the knife is turned forward in a semicircular stroke. The posterior end of the brain-stem is gradually lifted up out of the mantle by elevating the cerebellum and medulla oblongata. The upper peduncle of the arch of the brain-mantle along the upper border of the island and the outer border of the corpus striatum is severed from the stem as far as the anterior end of the upper border of the island, which bends downward into the anterior border. The peduncle of the fornix with the pedicle of the septum and the lamina of the knee of the corpus callosum are severed close above the anterior commissure, and the knife following the anterior border of the island is carried downward from the head of the corpus striatum. The remaining connections between the frontal lobes and stem are put on a moderate stretch and the incision is completed by bringing the knife back into the first cut made from the opposite direction parallel with the orbital surface over the upper surface of the stem. The three arms of the cerebellum are then severed and the brain-stem, consisting of the island of Reil, the basal ganglia, crura, pons, medulla and cerebellum, is completely freed and lifted out of the mantle.

A combination of the Meynert and Virchow methods is used by many. The lateral ventricles are opened and an incision made along the fornix into the descending horn. The stem-ganglia are then cut out and brain-mantle and stem separated. The hemispheres are then cut by frontal sections made from the anterior end as far as the central convolutions. From the central convolutions backward horizontal sections are then made; the series of sections are numbered in order and fixed and hardened for microscopic examination.

It is evident that the section of the brain can be modified to meet the individual requirements, according to the nature, location and extent of the lesion and the character of the study to be made of the latter. The brain may be fixed and hardened either before or after sectioning.

The basal dura is next removed by means of forceps and knife, chisel or dura-forceps. The bones are then carefully examined for fractures, caries, etc. Particularly in cases of middle-ear disease, meningitis, etc., should the dura be removed from the temporal bone and the latter carefully examined.

The external auditory canal may be opened and the outer surface of the ear-drum examined by carrying the anterior flap of the scalp downward and forward until the entrance into the bony canal is reached. The external ear is then cut off close to the bone, using slight pressure so as to avoid tearing out the lining of the canal or injuring the tympanum. The anterior bony wall of the canal, and a part of the lower, are then carefully chiseled away until the membrane is exposed. Any bony projections on the thicker upper or lower wall of the canal may be trimmed off to give an unobstructed view. When pathologic changes are present upon any part of the wall of the canal the latter should be opened from the other side so as to expose the condition fully.

The most important pathologic conditions of the inner meninges are anaemia, hyperaemia, stasis , oedema, hemorrhages , serous, purulent and fibrinous inflammation , chronic leptomeningitis , tuberculosis, syphilis , blastomycosis, actinomycosis and neoplasms. The last named are not common. Cholesteatoma, haemangioma, lymphangioma, endothelioma, fibroma, osteoma and lipoma represent the benign tumors found here. Primary sarcoma is the most common tumor, usually angiosarcoma, perithelioma, cylindroma, round-cell-, spindle-cell- or myxosarcoma. Secondary sarcoma and carcinoma occur. Animal parasites are cysticercus and echinococcus.

Hemorrhages may occur in any part of the brain, and may be large or small. Rupture into a ventricle is always fatal. The large hemorrhages are due to rupture of a diseased artery; small punctate hemorrhages throughout cortex are usually embolic . Old hemorrhages are brownish in color . Areas of softening are usually the result of embolism, thrombosis or sclerosis. They are usually yellow, yellowish-white or brownish-yellow or red.

The most important pathologic conditions of the brain are congenital defects or malformations , anaemia, hyperaemia, oedema, hemorrhage , embolism, thrombosis, arteriosclerosis, aneurism, anaemic infarction, encephalomalacia , pigmented scars, atrophy, secondary degeneration, encephalitis, , sclerosis , tuberculosis, syphilis, actinomycosis, blastomycosis, rabies, primary neoplasms , primary epithelial tumors of ventricles, pineal gland and hypophysis , metastatic tumors , cysts, parasites and traumatic lesions . Especial examination of the brain should be made in all cases of acromegaly, epilepsy, cretinism, congenital idiocy, degeneracy, criminal tendency, insanity, chorea, caisson disease, locomotor ataxia, paralysis agitans, syringomyelia, spastic paralysis, infantile paralysis, hereditary ataxia, rabies, all forms of paralysis, motor or sensory disturbances and neuritis.

The fat-tissue in the orbits should be yellowish-white; from it the red muscles and the white nerves should be easily distinguishable. On section of the eye-ball the vitreous normally is clear and the retina uniformly grayish-black and smooth. The most common and important conditions to be looked for are phlegmonous inflammations, purulent panophthalmitis, orbital hemorrhage, thrombosis of ophthalmic vein and sinus cavernosus leading to pachy- and leptomeningitis, neoplasms of orbit, wall of orbit, eye-ball or lachrymal gland , affections of individual muscles , atrophy of optic nerve, choked disk, retinitis, choroiditis, iritis, glaucoma, etc.

Note condition of scalp about ear, condition of external canal , condition of periosteum, particularly over the mastoid process , condition of bone after removal of periosteum . Inflammatory oedema, purulent infiltrations in the soft parts, collections of pus beneath the periosteum, roughness of bone beneath elevated periosteum, presence of pus or blood in external auditory canal, perforations of drum, etc., should be noted. Normally the drum should be grayish-white and shining. Note contents of middle ear, Eustachian tube, condition of ossicles, mastoid cells and bone. Lining of middle ear should be grayish-red and smooth; the cut edges of bone should be uniformly grayish-red. When infiltrated with pus they are brown or greenish. The mucous membrane is deep-red or greenish in purulent inflammation; yellow, creamy pus, often of very offensive odor, may be found in middle ear, Eustachian tube or external canal. Note character of perforations; old ones have smooth and thickened edges. The most important pathologic conditions are: otitis media purulenta, inflammation of mastoid cells, caries of mastoid process, sinus-thrombosis , otitis media tuberculosa, granulomatous polypi, cholesteatoma, sclerosis, congenital anomalies, foreign bodies, parasites, neoplasms .

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