Treatment.

With the object of reducing the infectivity of the protruding brain, fomentations have been advocated. From my own experience, however, it would appear that their application tends to increase the degree of protrusion, and that better results may be obtained by keeping the exposed brain as dry as possible, painting over with a 2¹⁄₂ per cent. solution of iodine in rectified spirit, dusting with antiseptic powder, and protecting with dry dressings, frequently replaced.

In the event of failure to improve the condition by means of these minor remedies—a too-frequent occurrence—excision of the protruding mass may be regarded as a perfectly justifiable procedure, providing that the hernia does not include the cerebellum or motor cortical region. The protrusion is shaved away flush with the level of the skull, the raw surface of the brain lightly painted with iodine, dusted with iodoform or other antiseptic powder, and protected with gauze and wool.

The prognosis is necessarily most grave, but the most astounding recoveries have taken place under this mode of treatment.

CHAPTER IX
BULLET-WOUNDS OF THE SKULL AND BRAIN

In the consideration of bullet-wounds of the skull and brain the following factors must be taken into account:—

The velocity of the bullet.

The distance at which the bullet is fired.

The size of the bullet.

The nature of the bullet.

The angle of impact.

The position of the bullet at the moment of impact.

Before, however, noting the varying effects on the skull as produced by one or more of these factors, it will be necessary to allude briefly to the average effect on the skull as produced by bullet-wounds in general.

‘When a foreign body passes through any part of the skull—it matters not what the direction may be—the aperture of exit is always greater than the aperture of entry.’ Such was the law enunciated by Teevan in 1864. The explanation is as follows: ‘The aperture of entry is caused by the penetrating body only, whilst the aperture of exit is larger, insomuch as it is made by the penetrating body plus the fragments of bone driven out of the proximal table and diploe.’ It might also be added that the greater degree of damage will always be incurred by the unsupported table—the internal at the wound of entry, the external at that of exit.

The size and shape of the aperture of entry through the external table bears a close resemblance to the size and shape of the entering bullet. As a general rule, it is round or oval, and presents clean-cut edges with some small radiating fissures. The aperture of entry through the internal table is larger, the margins inverted towards the brain, the radiating fissures more pronounced, and small fragments of bone in-driven towards the brain.

In the event of perforation of the skull through the medium of a high-velocity bullet, the aperture of exit through the internal table closely resembles that through the external table at the site of entry, with the exception that it is influenced by any changes in position that the bullet may have undergone during its transmission through the brain. The wound of exit through the external table is again greater than that through the internal—in accordance with Teevan’s law—the margins everted, the surrounding bone fissured or comminuted, whilst fragments of bone may be driven out beneath the lacerated scalp, or even blown completely away. On the other hand, when the bullet is fired at close range, the aperture of exit is often considerably larger than that of entry—due, in all probability, to superadded explosive effect.

The effect of the velocity of the bullet on the fracture:—The greater the velocity of the bullet the greater the resemblance of the wounds of entry and exit to the size and shape of the bullet, the ‘cleaner’ the holes, and vice versa.

The effect of distance:—When the bullet is fired from a distance, but with full effect, the hole is clean cut and presents the characteristics enumerated above. When the bullet is ‘spent’, the osseous injury at the point of impact is usually of a more extensive character than when the bullet possesses a higher degree of velocity. When fired at close quarters the damage incurred from the impact of the bullet is increased by the force of the forwardly driven air and gas. The skull suffers proportionately, the scalp being severely lacerated, burnt, and circumferentially ingrained with powder, the bone extensively comminuted, and the brain severely lacerated.

The effect of size and shape of the bullet:—The effects produced on the skull in relation to the size and shapes of the bullet are so obvious as to require no description. The nature of the bullet must also be taken into consideration, whether of the soft-nosed variety, expansile, &c.

The effect of the angle of impact:—The lesion produced by the bullet varies according as to whether the bullet glances across the vault or strikes the bone at right angles. In the former case a ‘gutter’ fracture may result, varying in degree and associated brain complication according to the angle of impact. In the latter case the skull is penetrated or perforated.

The effect of the position of the bullet at the moment of impact:—The bullet, at the moment of impact, may be so changed in position—head-over-heels, ricochet, &c.—that the skull may be struck by its long axis instead of by its nose. In such cases, the wound of entry will be more extensive than under ordinary circumstances.

It is obvious, therefore, that many factors require consideration in estimating the extent of the osseous lesion and the nature of the complications existent in any given case. Due allowance must also be paid to other factors entering into the case, more especially in relation to the weapon used—pistol, revolver, gun, &c.

Injury to the bone.

The various injuries to bone may be classified as follows:—

Fractures limited to the external table.

Fractures limited to the internal table.

Gutter fractures.

The complete fractures produced by a penetrating wound.

The complete fractures produced by a perforating wound.

Fractures limited to the external table.

Fractures of this nature are of exceedingly rare occurrence. They are produced by a bullet which strikes the skull in such an oblique direction that the scalp and external table are torn away (‘gutter’ fractures), or by a bullet which, directed against the outer wall of the frontal sinus, possesses sufficient force to comminute the outer wall of that sinus, but, from loss of momentum, is incapable of penetrating further.

Fractures limited to the internal table.

These fractures are even more rare than those described above. Their occurrence is probably only possible when the bullet strikes the skull in a markedly oblique direction, and with greatly diminished velocity—‘spent’ bullets. I believe I am correct in stating that only one instance of this particular variety of fracture was observed in the South African War. In any case, they are of such infrequent occurrence that they may be practically disregarded.

Gutter fractures.

Gutter fractures are almost invariably dependent on the impact of a glancing bullet. They may be arranged in three groups, according to the extent of the osseous lesion.

1. Where the external table is blown away, leaving the internal table exposed, perhaps comminuted.

2. Where the internal table is driven in the inward direction, pressing on, irritating, and perhaps lacerating the dura mater.

3. Where the whole thickness of the bone is blown away, leaving a gaping wound from which brain-matter may protrude.

The complete fractures produced by penetrating and perforating wounds.

The general effects as produced by penetrating and perforating bullet-wounds of the skull and brain are depicted in Fig. 88, and described in the text associated with that figure.

Injury to the brain.

Brain lesions vary ‘from a single track with small points of extravasation in neighbouring areas to a condition of hæmorrhagic pulp, which latter condition is the result of injury from the projectile associated with bleeding, often extensive, into neighbouring areas, disintegrating and pulping the brain-substance. These latter cases are generally fatal, and are accompanied not infrequently with meningeal and ventricular hæmorrhage’ (Bowlby).[59]

The worst degrees of brain-injury arise when the injury is inflicted at close range, more especially at the site of emergence of a perforating bullet, the damage to the soft parts being there magnified by the waves and vibrations set up by the bullet during its passage across the brain. In many cases also the brain is dashed as a whole against the opposing osseous barrier (laceration by contre-coup).

The general effects produced on the skull and brain by a perforating bullet of high velocity are shown in Fig. 88.

Symptomatology.

It is unnecessary to enter into details with regard to the symptoms arising from bullet-wounds of the skull and brain, for they closely resemble those previously enumerated in the chapters dealing with fractures of the skull and injury to the brain. There are, however, a few special points to which attention should be directed.

1. External hæmorrhages are seldom profuse.

2. The escape of cerebro-spinal fluid is of infrequent occurrence, probably due to the fact that the apertures of entry and exit are blocked up with scalp, fragments of bone, and pulped and swollen brain.

3. Concussion and irritation are prominent symptoms, compression is rarely seen in its typical form. As Spencer[60] says, ‘The dominant feature is usually concussion. The extent of the paralysis depends on the region injured, and there is often at first extensive temporary paralysis from vibratory concussion of the brain substance suspending its functions over a wide area around the bullet-track.’ Cerebral irritation and Jacksonian fits are frequently observed.

Indications for operation.

There is a great uniformity of opinion with regard to the indications for operation as expressed by those who have had considerable experience in wounds of this nature. One has only to glance through the works of recognized authorities—Spencer,[61] Bowlby,[62] Makins,[63] Lawford Knaggs,[64] &c.—to see that it is an accepted rule that all bullet-wounds of the skull and brain call for early operative interference, it being granted that the condition of the patient is compatible with such treatment.

Operation.

The operative details may be considered under two headings:—

(a) The exploration of the wounds of entry and exit.

(b) The search for and removal of the bullet.

The exploration of the wounds of entry and exit.

Whether the skull be penetrated or perforated, the wounds are investigated after similar general principles. After careful shaving and cleansing of the whole scalp, and after application of the scalp-tourniquet, a scalp-flap is turned down, the centre corresponding as far as possible to the site of entrance or emergence of the bullet. The under aspect of the flap is examined for loose fragments of bone, hair, portions of headgear, &c. These are removed and the flap cleansed. The bone is next examined. All loose fragments are removed, both large and small. The smaller are discarded, the larger are boiled (for ten minutes) and preserved in hot saline solution for replacement at the termination of the operation, if such a course should be deemed advisable (see p. 132). Those fragments of bone which retain their pericranial attachments are merely elevated and turned aside, to be again placed in position at the proper time.

Trephining is seldom necessary, the hole in the bone usually allowing of the application of craniectomy forceps, if any enlargement should be requisite.

A good view of the dura mater can now be obtained. If that membrane be merely punctured or incised, the tear must be enlarged with blunt-pointed scissors so as to allow of complete examination of the underlying brain. Hæmorrhage from meningeal vessels is controlled by the application of ligatures to all vessels that cross the line of dural section.

The lacerated brain is gently irrigated with saline solution (at a temperature between 110° and 115° Fahrenheit), and all blood and pulped brain matter washed away. The cortex is then lightly examined with the finger and probe for any fragments of bone that may be embedded in the brain substance. The removal of such fragments should be conducted with all possible gentleness. The surgeon should be satisfied that no foreign body remains. The bullet, when encountered, is removed. Needless to say, the presence of a bullet and the existence of in-driven fragments of bone should be investigated previous to the adoption of operative measures by means of X-ray photography.

If the brain be penetrated or perforated a drainage tube is introduced through scalp-flap and dura mater in such a manner that its distal end lies in relation to the track through the brain or flush with its lacerated surface. Elsewhere the dura is sewn up (fine catgut sutures) and the scalp-flap replaced, the drainage tube being anchored to the scalp with a single suture. The tube should be allowed to remain in situ for at least forty-eight hours and longer if necessary, the surgeon being guided by the amount of discharge and by the general progress of the case. In all cases of doubt the surgeon should err on the side of leaving the tube in position for a longer period of time, merely shortening it daily. Premature removal may lead to disastrous results. There can be no question that ultimate success hinges to a large extent on primary or early healing of the wound.

The search for and removal of the bullet.

In the event of a wound of entry only, it may be presumed that the bullet is within the skull. Bullets, however, pursue such unexpected and devious courses within the skull, and possess such a tendency to gravitate towards the base of the brain, that no attempt should be made at removal except after full X-ray investigation, stereoscopic if possible.

To this rule there are two exceptions:—(1) where the bullet lies superficial in the brain substance, and (2) where there exists, at the opposite side of the skull, what may be termed an area of attempted exit, that is to say, an area of bone elevation and blood extravasation, suggesting that the bullet has penetrated through the brain and impinged against the opposite side of the skull. In both these instances operative measures are not only justifiable but often definitely indicated. On the other hand, it cannot be urged too forcibly that hasty and ill-determined explorations usually terminate in failure. Even under the most promising circumstances it by no means follows that the bullet will be found at the site of counter-trephining, as it may have rebounded to some more distant region of the brain, necessitating an operation conducted over a totally different region. Thus, in a case recently under my care, the bullet entered at the right temporal region, penetrated the brain and produced on the left side of the head a well-defined wound of attempted exit. The bullet, however, on striking the opposing side of the skull rebounded, and was subsequently found in the apex of the descending cornu of the right lateral ventricle. This case affords a good example of the uncertain course pursued by bullets entering the cranial cavity.

However, in certain cases of emergency and in others of expediency an immediate search should be made for the bullet. The operation should be carried out with a light hand and not unduly prolonged.

In order to find and remove the bullet various probes and extractors have been invented. Perhaps the best of these is Sheen’s bullet-forceps, probe, and telephone-detector.

‘The forceps are so constructed that they may be attached directly to the telephone-detector and used as a combined probe and forceps, or they may be used in combination with the specially designed graduated probe attached to the detector in the following manner: The bullet having been located with the probe, the forceps are introduced along the probe, the jaws of the forceps being provided with an oblique groove for this purpose. In both methods of use the telephone-detector is in uninterrupted contact with the bullet during extraction, an advantage which much facilitates the operation, and ensures the least possible damage of tissue. In cases where the forceps are used as a probe and forceps combined, the connexion attached to the forceps is composed of silver wire, which can be readily sterilized, and while of sufficient rigidity to avoid risk of accidental short-circuiting with the patient’s body, is flexible enough not to interfere with the delicacy of manipulation. The telephone-detector is placed on the head of the operator, and the flat plate on the patient’s body, good contact being secured by means of a damp roll of lint, or other material, moistened with a saturated saline solution.’

‘The probe is introduced, and when a metallic foreign body is touched a fall of potential occurs, and the telephone buzzes. It is necessary to point out that no mistakes can be made, as may be the case with a battery in circuit. In using the “auto-telephone probe” the body constitutes an electrolyte, the plate one pole of a voltaic circle, the probe the other; on touching a metallic body different to that of the probe, a difference of potential occurs, and the current ensuing flows through the telephone and is recorded by the diaphragm in the usual way.’[65]

If the bullet be not found it should be allowed to remain in situ till such time shall have elapsed as will enable the surgeon to determine whether further operative measures are indicated, time being allowed also for skiagraphy and for the evolvement of another plan of campaign. It is of course a well-known fact that bullets in certain regions of the brain—e. g. the frontal lobe—may exercise but little effect on the individual. Further measures are also indicated when the want of cleanliness of the wound and the anatomical situation of the bullet demand secondary operative procedures. All remote operations are planned according to the localizing symptoms, aided by X-ray photography.

After exploration for and removal of the bullet an extensive osseous defect may remain. Opinions differ with respect to the time at which an attempt should be made to remedy the deficiency and as to the operative technique appropriate to the condition. The nature of the wound must always be taken into consideration, for the application of any plate of foreign material is doomed to failure in the event of the slightest degree of suppuration. As a general rule, it may be accepted that it is advisable to postpone such measures till after the primary or early healing of the wound. Further delay, however, tends to allow of the formation of such adhesions as will result in the development of Jacksonian epilepsy, chronic headache, traumatic insanity, &c. The operative features requisite to the interposition of plates between the bone and the scalp, and other measures, are fully detailed in Chapter VI.

‘The after treatment consists in keeping the patient as quiet as possible, and the administration of a fluid diet. In some cases, recurring symptoms pointed to the continued presence of bone fragments; these were usually indicated by signs of irritation, or often by local inflammation, in the latter case infection taking the greatest share in the causation. Such cases needed secondary exploration, and the wonderful success of this operation, even when the wound was evidently infected, was perhaps one of the most striking experiences of surgery in general.’ (Makins.)[66]

Complications.

The more important early complications are meningitis, hernia cerebri, and brain abscess. For the Symptomatology and Treatment of these conditions the reader is referred to Chapter VIII.

Results.

The prognosis in any given case depends on the degree of bone and brain injury, on the presence or absence of the bullet in the brain, and on the ‘cleanliness’ of the wound. In the American Civil War 61·2 per cent. of all fractures of the skull terminated fatally, in the Franco-German War 51·3 per cent., and in the South African War 33·1 per cent. This decreasing mortality is undoubtedly dependent on the improved methods of treatment.

When the injury is inflicted at short range the prognosis is undoubtedly less favourable. ‘At short range, the characters of the wounds, and the severity of the symptoms, rendered the immediate prognosis uniformly bad, a very great majority of the patients dying, and that at the end of a few hours or days.’ (Makins.)

The best results were obtained when the injury was received in the frontal region. The occipital region comes second, and the cerebellar last. Most injuries near the base of the skull were fatal. Longitudinal wounds were more serious than transverse. However, the most surprising recoveries were made, both with and without operative treatment.

The prognosis with regard to pistol wounds is absolutely bad. Phelps[67] records the following results in cases that came under his own observation.

Death occurred at once or within the first hour in 15 cases.

Death occurred within twelve hours in 7 cases.

Death occurred within fifteen hours to forty days in 10 cases.

Recovery in but 8 cases.

The more remote results are exceedingly difficult to determine, for it is impossible to obtain an accurate account of the subsequent course of events in all cases. With regard to the question of the after-history, Makins[68] writes, ‘I feel certain that a long roll of secondary troubles from the contraction of the cicatricial tissue, irritation from distant remaining bone fragments, as well as mental troubles from actual brain destruction, await record in the near future.’ In the experience of the writer, this statement is fully justified. The hospital surgeon continually meets with cases exemplifying the more remote effects, varying from slight lesions associated with chronic headache to others showing considerable deficiency in the vault of the skull with cortical degeneration.

Some of these cases are still capable of being cured, others are hopelessly inoperable.

In the consideration of the more remote results, it must be remembered that the surgeon comes mainly into communication with those cases which require further treatment. The more favourable are lost to view. Hence the difficulty in estimating with certainty the absolute results obtained after lesions of this nature.

CHAPTER X
TRIGEMINAL NEURALGIA

Neuralgia of the fifth or trigeminal nerve is, in its varying degrees, of frequent occurrence. In its cause, manifestations, and progress, it offers so wide a field for discussion that the question must be focussed down by means of some simple form of classification such as enables one to include the majority of cases that come before one’s observation.

For all practical purposes, the following types will be sufficiently inclusive:—

Neuralgia minor.

Neuralgia major.

Hysterical neuralgia.

NEURALGIA MINOR

This variety is almost invariably dependent in its development on some exciting cause. In some cases this cause is readily demonstrated, in others great difficulty may be experienced before the source is discovered.

These secondary neuralgias may be regarded as resulting from the following injuries and diseases.

Diseases of the tongue, fauces, and pharynx. For example, the pain referred to the lingual nerve in epithelioma of the tongue.

Diseases and injuries of the maxillæ. For example, the neuralgia associated with dental caries.

Injuries and diseases of the nose and its accessory cavities. For example, the infra-orbital pain experienced in empyema of the antrum.

Injuries and diseases of the bones of the skull. For example, the pain referred along the course of those nerves emerging through the basal foramina involved in a fracture of the base of the skull.

Errors of refraction. For example, neuralgia of the supra-orbital nerve.

Anæmia, influenza, alcoholism, Bright’s disease, cold, worry, malaria (brow-ague), rheumatism, &c.

But slight allusion need be made to the symptomatology of neuralgia minor—the conditions are more or less familiar to every one. The pain, though usually most intense in that particular branch of the nerve which is most intimately related to the source of the neuralgia, is often referred to other branches of the same nerve-trunk, and sometimes to an entirely different nerve. Thus, in the case of an epithelioma of the tongue, the pain, though perhaps most acute in the region supplied by the lingual nerve, is nevertheless frequently referred to the ear along the course and distribution of the chorda tympani.

The pain is more or less continuous, often associated with exacerbations, but seldom paroxysmal. The patient frequently complains of heat and tenderness over the areas supplied by the nerve in question and, in almost every instance, there are points of special tenderness corresponding as a rule to the emergence of the nerve-trunk through some osseous foramen. Again, some relief may be obtained by the application of pressure over the site of that foramen. For example, neuralgia dependent on antral empyema is most acute in the region of the infra-orbital foramen, and relief may be experienced by pressure applied over that foramen.

In the event of failure to discover an exciting cause, some difficulty may be experienced in coming to a correct conclusion as to whether the case belongs to the minor types of neuralgia, or should be relegated to the more serious group of neuralgia major (tic doloreux). In general, however, the neuralgias minor may be distinguished from the major variety by the following features:—

(1) The presence of some detectable forms of nerve-irritation. In the neuralgias major there may be no such cause.

(2) The relief of symptoms on the successful treatment of the cause.

(3) The relative absence of those paroxysmal attacks which are so typical of neuralgia major.

(4) The infrequence of severe vaso-motor, trophic, and sensory changes in the regions supplied by the nerve affected. Such changes are more or less constant in neuralgia major.

(5) The wide distribution of the pain and its reference to other nerves, with no clear line of demarcation from neighbouring areas supplied by totally different nerves. In neuralgia major the pain, though often involving both second and third divisions of the fifth nerve, is referred to the areas supplied by those nerves only, with a clear line of demarcation from neighbouring regions.

In cases of neuralgia of doubtful origin one can only observe the effect of treatment and be guided by the results obtained.

Treatment.

The source of the neuralgia requires primary consideration. When this has been rectified the patient should be treated after general medical principles. In the event of failure at relief, we have two other strings to our bow—alcohol injections, and neurectomy of the nerve involved. Alcohol injections are dealt with later. Neurectomy—after Thiersch’s method of avulsion—is greatly preferable to all the older methods of neurotomy, nerve-stretching, and nerve-division. These older methods brought about in their train but transitory alleviation of pain.

Neurectomy of the inferior dental nerve.

A transverse incision is made through the skin and subcutaneous tissues at the level of junction between horizontal and vertical rami of the jaw, extending from the anterior border of the vertical ramus to the posterior border of the same. The tissues are retracted and the masseter muscle exposed. The muscle fibres are split in the vertical direction and the bone laid bare. A ¹⁄₂ inch trephine is applied, and a disk of bone removed so as to expose the inferior dental nerve at its entrance into the inferior dental canal. The nerve is freed from the corresponding artery, divided at the centre of exposure, and the two ends seized with forceps, twisted and avulsed in such a manner as to destroy and remove the maximum number of nerve-fibres. The disk of bone is replaced, the muscle fibres brought together with a few catgut sutures, and the margins of the skin incision approximated.

Exposure of the infra-orbital nerve.

A curved incision is made through the skin and subcutaneous tissues parallel to and below the infra-orbital margin, the tissues retracted, and the small muscles overlying the infra-orbital foramen divided or retracted so as to allow exposure of the foramen. The nerve is isolated and divided. The peripheral end is seized with forceps and avulsed. The central end may be treated after similar fashion, or, preferably, again exposed in the infra-orbital groove or canal, the tissues being peeled away from the floor of the orbit and the nerve sought for as it traverses the infra-orbital canal. With this object in view, it may be necessary to gently break away the osseous roof of the canal before the nerve can be exposed. It is then lifted up with a small hook, drawn through the infra-orbital foramen, seized with forceps, and avulsed in such a manner as to be torn away somewhere in the region of the spheno-maxillary fossa. The wound is then sewn up.

Exposure of the supra-orbital nerve.

The nerve is exposed through a curved incision parallel to the supra-orbital margin, and so planned as to be concealed by the eyebrow. The fibres of the orbicularis palpebrarum are separated and the foramen identified. The nerve is separated from its artery, divided, the peripheral portion avulsed, and the central portion again exposed as it courses along the roof of the orbit. For this purpose the tissues of the upper lid are detached from the supra-orbital margin, the nerve delivered with the aid of a small hook, brought out through the foramen, and avulsed in such a manner as to be torn away somewhere in the region of the sphenoidal fissure. The wound is then sewn up.

NEURALGIA MAJOR

Neuralgia major originates most commonly in the third division of the nerve, less frequently in the second, and rarely in the first. Whichever division be primarily affected, there is a very general tendency for other branches to become involved, and this in a very definite way—the pain spreading centrally from the nerve first involved, radiating to other nerve-trunks so soon as they shall be reached. Thus, pain originating in the inferior dental branch of the third division spreads to the lingual and other branches of that division and then involves the second division. Fortunately, whether the trouble originates in the third or second divisions, the ophthalmic tends to escape or to become less seriously involved—a fortunate circumstance considering the terrible conditions associated with neuritis of that nerve, the disastrous results on cornea, conjunctiva, &c.

The disease is undoubtedly of a progressive nature, originating without rhyme or reason. It seldom becomes evident before the ages of 45 to 55, affecting both rich and poor alike.

Wilfred Harris[69] collected 265 cases, and showed that the disease was slightly more common in men than in women—144 to 131. There appeared to be some predilection for the disease to involve the right side in preference to the left—179 to 80. In 6 cases the affection was bilateral.

Trigeminal neuralgia does not in itself lead to fatal results, but the continuous pain, the want of sleep, and the difficulty experienced in taking sufficient nourishment soon reduce the patient to such a miserable condition that, unless relieved by the surgeon, amelioration is sought in morphia or release in death.

Before proceeding further it will be convenient to enumerate certain points aiding in the differential diagnosis between the true and hysterical forms of trigeminal neuralgia.

The pathology of tic doloreux is most obscure. The parts requiring examination are the peripheral nerve-trunks, the ganglion, the sensory root, and the central nervous system. The last two regions may be excluded, not only on the ground that research has failed to show any constant structural changes, but also because the removal of the ganglion may be regarded as curative of the disease. The ganglion itself and the peripheral nerve-trunks remain for investigation.

In the peripheral nerve-fibres no constant material changes have been observed. The epineurium, on the other hand, is almost invariably shrunken and sclerosed. Considerable stress might be laid on this fact unless it were also taken into consideration that the nerves were examined in patients who had suffered from major neuralgia for prolonged periods of time. Similar changes have also been observed in patients who have never exhibited neuralgic symptoms.

In the ganglion itself the following changes have been observed:—(1) arterio-sclerosis; (2) alteration in the character of the nerve-fibres traversing the ganglion; and (3) adhesions between the ganglion and the surrounding parts. All these changes, however, are so inconstant that but little importance can be attached to them.

At the present time there is a disposition to regard trigeminal neuralgia in the light of an ascending neuritis, originating peripherally and ascending towards the Gasserian ganglion. Sir Victor Horsley first pointed out that the ganglion acts as a barrier to the further upward spread of the affection. This is proved by the success obtained in the removal of the ganglion.

Symptomatology.

Pain.

The onset of pain may be preceded by premonitory symptoms such as tinglings, throbbings, and burning sensations in the parts subsequently involved, whilst, in the earlier stages of the disease, the pain may be more or less localized to the site of emergence of the nerve from an osseous foramen.

In the earlier stages also the attacks, though severe, are paroxysmal, of short duration, perhaps not lasting more than half a minute, and definitely localized to some special nerve-trunk. During the periods of remission the patient feels quite well. Gradually the pain increases in severity, the periods of remission shorten, and the pain in its distribution becomes more widespread, the neuritis—or whatever the process may be—spreading centrally and radiating along the course and distribution of such branches of the nerve as shall be encountered.

Paroxysms are a marked feature, occasionally of so severe a nature that the patient falls to the ground as if struck by lightning, recovering after a variable period of time.

In the later stages of the disease the pain may be almost continuous, and the condition of the patient is truly miserable.

The attacks are often ushered in by the slightest stimulus—talking, mastication of food, draughts, emotion, &c.—and, in order to avoid the occurrence as far as possible, the patient abstains from talking, dreads eating, &c. Dribbling from the mouth may be observed in those cases in which the patient finds some relief in keeping the mouth open. It is also frequently seen during the height of the paroxysm. At such stages the patient is collapsed, with feeble pulse, shallow respiration, the temperature subnormal, and the skin clammy. The attacks occur both during the day and the night, sleep fails, and the body nutrition suffers.

The site at which the pain originates can often be fixed by the patient himself. Occasionally relief may be attained by pressure applied over some particular part, by heat or by cold, or by some other method discovered by the patient himself.

The attacks are often accompanied by twitchings of the muscles supplied by the facial nerve, and, according to some investigators, by fibrillary twitchings of the muscles of the region affected.

In the later stages, wasting of the muscles may be observed.

Vaso-motor and trophic changes.

The skin and mucous membrane supplied by the nerve involved become hyperæmic and hyperæsthetic, and, in the more chronic cases, these changes may be associated with œdema of the subcutaneous tissues—the clinical picture now closely resembling that observed in some cases of angio-neurotic œdema.

Other symptoms of similar nature are herpes, increased salivation, furred tongue (on the side of the lesion), sweating of the skin, lacrimation, conjunctivitis, and keratitis.

General decline in health.

This depends, not only on the difficulty experienced in taking sufficient nourishment, but also on the moral effect produced by the more or less continuous pain. In the more severe cases emaciation is rapid.

Treatment.

1. Therapeutic remedies. The following drugs have been recommended.

Quinine, in large and increasing doses.

Arsenic, given in a similar fashion.

Gelsemium, in toxic doses, every few hours until tinglings in the fingers and nausea show that the drug has been pushed far enough (Sir Victor Horsley).

Methylene blue, in three-grain doses (Sir Watson Cheyne).

Iron, antipyrin, strychnine, cannabis indica, &c.

Morphia. This drug is undoubtedly beneficial in its results, but the habitual use thereof is strongly contra-indicated, not only because of the temporary benefit received, but also because of the necessary increase in the quantity required to alleviate the pain. If persistently used the patient gradually develops the morphia habit.

Some of these remedies suffice for the neuralgias minor, but with regard to their action in cases of neuralgia major, their effect may be summed up as follows: ‘True tic doloreux has been the therapeutic despair of most physicians and surgeons,’[70] and ‘too often the operation is put off till the patient is addicted to the morphia habit, depleted in strength and vitality by drugs, sleepless nights, and years of intense suffering’.[71]

Until quite recently, with the exception of these medicinal remedies, the only other methods at our disposal in the treatment of trigeminal neuralgia were Gasserian ganglion removal and other intracranial operations on the three divisions of the fifth nerve. In 1906, however, Schlösser[72] of Munich advocated the injection of alcohol into the region of those foramina at the base of the skull through which the nerve trunks emerged. As the result of these injections it was stated that, although some slight degree of cutaneous anæsthesia frequently resulted, yet that it was usually of an unimportant and transient character, and that the pain subsided and finally ceased, remaining absent for a variable period of time, usually about ten months. In the event of recurrence the injection was repeated, each period of recurrent pain being less intense and less prolonged, whilst the periods of remission increased proportionately.

Whilst it is clear from the results obtained by those who have followed in Schlösser’s footsteps, that alcohol injections are, as a rule, reasonably satisfactory, yet it must be clearly understood that beneficial results are not always observed, and that in the event of failure the more radical intracranial operations must be carried out.

The technique of alcohol injections.

Question of anæsthetic. Freezing of the skin or other method of local anæsthesia suffices to allow of the painless introduction of the needle. A general anæsthetic should be avoided wherever possible, as the burning sensation experienced by the patient when the nerve-trunk is encountered greatly assists the accuracy of introduction.

The needle. The needle should be stout—10 cm. long, 1·5 cm. in diameter, and graduated in centimetres up to 5 cm., and provided with a blunt stilette.

Introduction. The skin is cleansed, the stilette slightly withdrawn, and the needle introduced. After puncture of the skin the stilette is pushed home, all further introduction being carried out with the blunt advancing point. When in position, the stilette is withdrawn, and a glass syringe, ready filled with alcohol, fitted to the needle and the injection made.

The solution. Purves Stewart recommends the injection of 1-1·5 c.cm. of the following solution:—