CHAPTER VII DIAGNOSIS OF INJURIES OF THE HEAD (Part 2)

82 SURGICAL DIAGNOSIS [chap. part struck, the depth from which the blood flows, and, in many cases, its long continuance. The blood may escape from the ear, nose, or pharpix; and in the latter cases, if the patient is recumbent, as he generally is, the blood is swallowed, and the haemor- rhage may only be revealed when altered blood is vomited. In other cases the blood trickles into the orbit, gradually forcing its way forwards under the conjunctiva, and then into the lids. If the fracture passes through the orbital arch, the blood escapes at once into the upper eyelid. In fracture of the posterior fossa the blood gets into the intermuscular planes of cellular tissue below the occiput, and only after some days reaches the surface and discolours the skin in this region. Cerebro-spLnal fluid escapes when the arachnoid membrane is torn, e.g. the arachnoid sheath of the olfactory lobe or of the auditory nerve. It may flow in considerable quantity from the ear or the nose, and the loss may continue for days. The flow is increased by anything that raises the intracranial pressure, such as coughing, straining, or compressioTi of the internal jugular veins; this sign should not be sought for, as the raised tension may affect the brain injuriously. The fluid is clear and limpid, specific gravity about 1002, faintly alkaline in reaction, and contains a trace of albumin and of a copper-reducing substance. When collected from the nose it becomes mixed with mucus, and gives a faint precipitate of mucin when acetic acid is added. It is distin- guished from mucus by its limpid character and the very small amount (if any) of mucin it contains, and from serum and inflammatory exudations by its low specific gravity and its containing a mere trace of albumin. If this fluid flows into the pharynx it is awallowed, and may be entirely unnoticed. In very viij FRACTURE OP BASE OF SKULL 83 severe fractures of the base, portions of braiu matter may be forced into the nose, pharynx, or ear. Injury to cranial nerves is shown by motor or sensory paralysis. {See p. 95.) It must be borne in mind that the base of the skull may be fractured without giving rise to any symptoms by which it can be recognized. And a fracture of the base is by no means easy to detect in good stereoscopic skiagrams. The surgeon is more likely to overlook fractures that exist than to diag- nose the injury wrongly when they are not present. L After an injury to the head or upper part of the face, an effusion of blood under the ocular ccn- junctiva, which may or may not spread subsequently to the eyelids (usually reaching the lower before the upper lid), indicates a fracture of the roof of the orbit. Hsemorrhage into the eyelids may be caused by a simple contusion (black eye), or by a fracture of the malar or upper jaw bone; in these cases sub- conjunctival hemorrhage is absent, or is much less marked than the effusion into the lids. In fractures of the roof of the orbit and of the orbital arch, in which the periosteum lining the orbital cavity is not torn, the blood does not get under the conjunctiva, but only into the lids, and in such a case a diagnosis can only be made by the aid of a skiagram. 2. If, after an injury to the head or nose, heemor- rhage from the nose continues for some hours, or even for a day or more, and especially if succeeding the flow of blood there is a discharge of cerebro- spinal fluid from the nose, or permanent anosmia, there is a fracture of the roof of the nose. 3. If, after an injury to the middle zone of the vault of the skull, or a heavy fall upon the feet or the buttocks, there is bleeding from the ear con- tmmng for many hours, and if the blood is seen to 84 SURGICAL DIAGNOSIS [chap. flow from the tympanum, there is a fracture of the middle fossa of the base of the slcull, involving the middle ear. A copious flow of cerebro-spinal fluid from the ear is still more conclusive evidence of fracture, and shows that, in addition, the arachnoid membrane is torn. Facial palsy and unilateral deaf- ness strengthen the diagnosis of fracture. Transient hsemorrhage may be caused by lacerations of the meatus or of the membrana tympani ; a slight flow of watery fluid might possibly be an escape of liquor Cotmmii from the inner ear ; if the fluid is richly albuminous it indicates that it is blood serum or inflammatory exudation. 4. If a patient who is known to have received an injury to the head, or may have received such an injury, after an interval vomits some dark, slightly altered blood, it becomes highly probable, in the absence of evidence to the contrary, that the blood has flowed into the pharynx from a fracture of the base of the skull, and been swallowed. The lips, mouth, and tongue should be carefully exam- ined to exclude haemorrhage from that source. If there is bleeding from the nose at the same time, or there are signs of such immediately after the acci- dent and before the patient assumed the horizontal position, and if he is conscious of swallowing blood, or, when unconscious, if the movement of deglutition is seen to occur spontaneously from time to time, and especially if on inspection, or on passing the finger to the back of the mouth, blood is found in the pharynx, the diagnosis oi fracture of the base of the skull IS assured. In the absence of other evidence it will 1)0 impossible to determine which fossa is injured, as the blood may flow into the pharynx from the nose, or the car, or from a fissure in the vault of the pharynx. vn] INTRACRANIAL LESIONS 5. When, after an injury to the posterior part of the skull, or a fall upon the feet or the buttocks, a puffy swelling appears around the mastoid process, or on the side of the neck, or below the occiput, and it steadily increases in size for some hours, it indicates a fracture of the posterior fossa of the base of the skull. The diagnosis is more certain when it is known that the swelling is not over the part struck. IV. Lesions of the Cranial Contents Intracranial lesions cause either irritation or far- alijsis of the nervous apparatus. Irritation of motor structures is shown by 7nuscular ttvitchmgs or spasms : irritation of sensory parts causes pain and hyper- OBSthesia ; irritation of reflex nerve-centres leads to increased reflex action. Motor palsy is estimated by noticing the position ot the limbs, the absence of all resistance to passive movements, and stertorous breathing or flapping of the lips and cheeks with respiration. Sensory palsy is recognized by the insensi- bility of the patient to all external impressions, such as sound, light, pinching, pricking, and heat. Reflex , palsy is specially indicated by a fixed condition of i the pupils, and the failure of contact with the con- i junctiva to cause contraction of the orbicularis pal- ! pebrarum. From these symptoms the surgeon must attempt to define the position and the nature of tlie I lesion. The pulse and respiration must be specially I observed. Long-drawn, slow respirations indicate I stimulation of the respiratory centre in the medulla while irregular, shallow, frequent respirations— or a Cheyne-Stokes rhythm— point to its exhaustion and paraly.sis. Similarly a slow, full, " labouiod " pulse of high tension indicates stimulation of \w cardio- 86 SURGICAL DIAGNOSIS [cHAr. inhibitoiy aud vaso-motor centres, and a rapid jjidse of low tension results from their exhaustion. Position of a lesion. — {a) Paralysis or irrita- tion of a single nerve, or of nerves lying close to- gether in the skull, is probably due to some lesion of the nerve-trunk or trunks on the same side ; e.g. paralysis of the fourth cranial nerve (n. trochlears), or of the facial and' auditory nerves, (h) When, however, the paralysis or the irritation affects nerves whose controlling cortical areas lie in close juxta- position, it indicates a cortical lesion of the opposite side, (c) If the palsy affects a very wide extent of muscles, it points to a lesion of some part of the main strands of the nerve-fibres in the central nervous system passing from the cortical centres to the nerves of distribution ; e.g. ordinary hemiplegia from haemorrhage into the corpus striatum. Electricity in diagnosis. — Although electricity is not largely used by surgeons for purposes of diagnosis, there is one way in which it may afford valuable aid in determining the position of a paralysing lesion. It depends upon the fact that, when a nerve- trunk or its centre is injured, the irritabiUty of the paralysed muscles to the faradic current rapidlj' diminishes until it finally disappears, while they respond more readily to the constant current, and the anodal contraction is stronger than the kathodal. This is known as the reaction of degeneration. It can be observed within a few days of the onset of par- alysis, and becomes more and more marked ; it is always associated with rapid wasting of the affected muscles, and occurs after injury to either cranial or spinal nerves. Where, therefore, paralysed muscles do not sliow this reaction of degeneration, it is to be accepted as certain evidence that the lesion is situated in some part of the nervous apparatus VII] INTRACRANIAL LESIONS 87 above the nerve nucleus. This sign tells us nothing of the cause of the paralysis, only its site. The natiu'e of a lesiou is indicated partly by the class of symptoms which it occasions, and partly by their time of onset, (a) Irritation is caused hy slight compression, by superficial or partial laceration of the brain substance, or by inflammatory con- gestion ; it rarely afiects the cranial nerve-trunks. {b) Paralysis is caused by complete laceration of brain or nerve, by firm compression by bone, blood, or inflammatory exudation, or by shaking up of the brain with more or less appreciable contusion, or by shock, (c) Symptoms produced immediately by an injury are caused either by concussion of the brain or by compression by displaced bone, (d) Symptoms coming on within a short interval of an injury (an interval measured by hours) are due to the pressure of effused blood or serum, (e) Symptoms arising later are the result of inflammation or cicatrization. Cerebral localization. — The motor area oc- cupies the precentral or ascending frontal convolu- tion, and a small part of the marginal convolution on the mesial surface of the hemisphere. It is divided up into several distinct centres ; those for the face, the neck, the arm, the trunk, and the leg are arranged in this order from below up. The face centre embraces the lower end of the fissure of Rolando (sulcus cen- trahs) ; its lower part, close to the fissure of Sylvius (fissura lateralis), governs the muscles of mastication and those of the larynx ; the upper part controls the upper face muscles and the platysma. The arm centre is the largest, and occupies the middle part of the precentral convolution ; the centre for the thumb extends over a great part of it ; the fingers, wrist, elbow and shoTilder are represented in centres which He in this order from below ujj. The leg centre is the 88 SURGICAL DIAGNOSIS [chap. upper end of the precentral convolutiou, and extends to the mesial surface of the hemisphere ; its anterior part is concerned witli movements of the thigh and leg, while its posterior part governs movements of the foot and toes. The centre for the trunk is intermediate between those for the arm and the leg. The centre for eye movements is in tlie second and third frontal convolutions. Sensory areas. — The area for general tactile sensation, temperature and muscular sense is situated in the postcentral convolution, and the area for sensation of any particular part probably lies immediately behind the motor centre for that part. No centre for the sensation of pain has yet been found in the cerebral cortex. The visual centre occupies the cuneate portion of the occipital lobe and the angular and supramarginal convolutions ; each occipital lobe is connected with the temporal half of the retina of the eye on the same side, and the nasal half in the eye of the opposite side. The auditory centre is in "the superior temporo-sphenoidal gj^rus, and receives impressions from each ear. The centre foi smell and taste is in the tip of the temporo-sphe- noidal lobe in the vicinity of the uncinate gyrus. There are three centres concerned mth sfeecli, and in a right-handed subject they are always on the left side of the brain. The auditory tvord centre is situated in the posterior part of the superior temporal convolution : its destruction causes total word-deafness. The visual speech centre is in the left angular gyrus : its destruction causes word- blindness or visual aphasia. The motor speech centre is in the posterior part of the third left frontal con- volutiou (Broca's area) : its destruction causes motor aphasia. There seems to be a ivriting centre also on the left side of the braiu, in or near the area govern- viij INTRACRANIAL LESIONS 89 ing movements of the hand : its destruction causes agraphia. To delineate these centres on the scalp, the main thing is to fix the position of the great fissures. The Inngitudinal fissure (fissura interhemispherica) is in- dicated by a line drawn over the vertex from the glabcUa to the occipital protuberance. The upper end of the fissure of Rolando (sulcus centralis) is in. behind the mid-point of this line, and it lies lieneath a line o\ in. long, drawn obliquely forwards and downwards from this point at an angle of 67" with the vertical median plane. The fissure of Sylvius (fi.ssura lateralis), 3i in. long, is beneath a line drawn from J in. below the parietal eminence to a point 1;^ in. behind the external angular process. With these lines fixed, the centres can be filled in with suSicient acciu-acy for all surgical purposes. The primary lesious ol the cranial contents are the following : Concussion. Contusion and laceration. Compression. To arrive at a diagnosis, notice especially the time and order of the onset of the symptoms, and pay attention to the state of the patient's consciousness, to any spasm or paralysis present, to the size and irritability of the pupils, the force and frequency of the pulse, the rhythm and fullness of respiration, the presence of laryngeal stertor, or of puiSng of the lips and cheeks, and the temperature and colour of the surface. The patellar reflex on each side should be carefidly observed. The symptoms of concussion of the brain vary Nvithin very wide limits— from a momentary giddi- ness to mstant death— and, when well marked,\heir iluration varies from hours to days. They are most 90 SUKGICAL DIAGNOSIS [chap. intense directly after the injury, and when they are found to increase in severity it is always due to something superadded to simple concussion — gener- ally to haemorrhage. The following statements may be made : 1. If after an injury to the head, or a general shake of the body, the patient is temporarily uncon- scious, with muscular relaxation (falling down) and pallor, or if he simply feels giddy, faint, and nause- ated, the symptoms are to be attributed to concussion of the brain in its milder form. 2. If immediately after such an injury a patient is found apparently quite unconscious, with com- plete muscular relaxation, the limbs being flaccid and motionless, and the urine and faeces passing in- voluntarily from relaxation of the sphincters, and the surface is pale and cold, the pulse small and soft (it is usually slow, but may be frequent), the respira- tion shallow and noiseless, the pupils sluggish, either unaltered in size or slightly dilated, the case is one of severe concussion of the brain. Except in the very gravest cases the patients show some response to a strong sensory imjsressiou : they will attempt to answer if loudly called, move away from a bright light or pungent odour, or flinch if j^inched. The patellar reflex is absent in the worst cases, but when present is equal on the two sides. 3. If the state of concussion — which is usually severe and prolonged — is followed by a condition of " cerebral irritation," contusion of the brain with consequent diffuse or generaUzed oedema is to be diagnosed. Cerebral irritation is recognized by the patient lying curled up on one side, quiet when left alone, but actively or even violently resenting attempts to move or rouse him, and with perhapsj^a low muttering delirium at- night. The pulse is full VII] INTRACRANIAL LESIONS 91 and bounding, and tile temi^erature somewhat raised, and, esi3ecially in children, there may be frequeiit 'oniiting. 4. Brain-matter (proved to be such by micro- •^copical examination) may be found mixed with the blood from the wound, in the hair of the scalp, or in the nose, ear, or mouth, or lying in a wound into the orbit ; this, of course, demonstrates laceration of the brain. It must be remembered that patients may present themselves with brain-matter thus extruded from the cranium without any symptoms to mdicate so grave a lesion— without either uncon- sciousness or paralysis. Apart from the loss of bram-substance or of cerebro-spinal fluid, lacera- tion of the brain may be suspected if symptoms ot concussion are followed by those of irritation, and especially by convulsions of groups of mus- cles which leave the convulsed parts paralysed •Severe laceration is usually followed by a rise in temperature to 101° or over. _ 5. Whenever after