Part 74 (2/2)

This is extremely rare as a result of a simple abscess of the brain, but is significant of encephalitis frequently a.s.sociated with meningitis (see p. 436). If an abscess be suspected, the brain should be explored as already described. If, however, no abscess be discovered, the treatment consists in removal of more bone and further incision of the dura mater, in order to permit of free drainage and to relieve tension.

(ii) Opening into the lateral ventricle. This may be due to rupture of its wall owing to the sudden diminution of pressure from too rapid drainage of the abscess cavity, or it may occur accidentally from thrusting in the exploratory instrument or drainage tube too deeply. Its occurrence is evidenced by the sudden gush of cerebro-spinal fluid. The ultimate danger is subsequent infection of the cavity, which, unfortunately, frequently occurs.

(iii) Cessation of breathing. This is more likely to occur in a cerebellar abscess in consequence of direct pressure on the medullary respiratory centres. The immediate treatment is to do artificial respiration and to open the cerebellar abscess by the quickest method possible. If this be successful, respiration probably will be restored.

=Prognosis and subsequent progress.= In an uncomplicated case a favourable prognosis may be expected, provided the abscess is successfully opened and drained without much disturbance of the surrounding parts. Many factors, however, may lead to a fatal result.

With regard to recovery: in 100 cases taken from the records of the London Hospital during the last ten years, recovery took place in 20% operated on for cerebral and 10% for cerebellar abscess. Other statistics give a much higher percentage of recovery, but it must be remembered that in hospital patients a large number of the cases are only seen by the surgeon at a very late stage, when the brain abscess is complicated by other intracranial or suppurative lesions, and the patient is in an almost moribund condition; so that the operation may only be undertaken as a forlorn hope.

If the operation is going to be successful, the head symptoms quickly disappear. Even if the patient was comatose before operation, the recovery may be so rapid that his mental condition may be almost normal within twenty-four hours. In many cases, if the abscess be a large one, convalescence will be tedious or prolonged; sometimes, indeed, complete restoration of the mental faculties, in spite of a most successful operation, will not be obtained. The chief relief to the patient is the cessation of the terrible headaches from which he has been suffering.

Unfavourable symptoms are the sudden onset of pyrexia accompanied by delirium usually the result of diffuse meningitis, or of infection of the lateral ventricles. In the latter case there is a rapid termination in drowsiness, coma, and death.

Although the brain abscess may be draining freely, the patient for some days may lie in a semi-comatose condition as a result of dema or inflammation of the surrounding brain tissue; in such cases prognosis is difficult, but hope of recovery may be entertained if the pulse and temperature keep practically normal.

=Recurrence of symptoms.= This may take place within the first few days after the operation as a result of infective cerebritis, the presence of another abscess, or faulty drainage; or at a much later period, owing to the formation of another abscess or to a cyst within the brain at the site of the former abscess.

1. If the recurrence of the symptoms appears immediately after the operation, the wound should be inspected carefully, if necessary under an anaesthetic. If drainage be not free, the tube should be removed and a pair of forceps inserted along the track leading into the abscess, their blades being then slightly opened and withdrawn. On doing this an acc.u.mulation of pus may escape. The cavity may then be irrigated gently with saline solution and a larger tube inserted.

If, however, this procedure does not give a satisfactory result, the finger may be inserted into the brain to feel if the abscess is loculated. By this means any existing septa may be broken through; or if a feeling of resistance suggests the presence of another abscess, this part of the brain can also be explored. It must also be remembered that although a temporo-sphenoidal abscess has been opened successfully and is draining well, the continuance of the symptoms may be due to a coexisting abscess of the cerebellum, or _vice versa_; in other cases, in spite of all care, the patient gradually sinks, partly from exhaustion and partly from general toxaemia, the result of infective cerebritis.

2. Recurrence of symptoms at a later period. The occurrence of a fresh abscess is usually owing to the fact that the primary focus of the disease has not been completely removed at the first operation; for instance, if the surgeon only trephined and drained the abscess without performing the mastoid operation.

A cyst is usually the result of the abscess having been encapsulated and its wall not having been removed at the first operation. If a cyst be discovered on exploring the brain in consequence of these symptoms, its wall should be removed if possible.

Apart from symptoms of intracranial pressure, the patient may suffer from attacks of Jacksonian epilepsy from time to time, presumably due to the post-operative adhesions. If they continue in spite of conservative treatment, it may become necessary to operate in order to remove this source of irritation (see Vol. III).

SECTION IV

OPERATIONS UPON THE LARYNX AND TRACHEA

BY

W. DOUGLAS HARMER, M.C. (Cantab.), F.R.C.S. (Eng.)

Surgeon to the Throat and Nose Department, St. Bartholomew's Hospital

CHAPTER I

ENDOLARYNGEAL OPERATIONS

=Indications.= (i) _Tumours._ Tumours of the larynx are more often innocent than malignant. Sir F. Semon[5] collected 12,297 cases seen between 1862 and 1888 by 107 laryngologists, and of these 10,747 (or 88%) were benign and 1,550 (or 12%) were malignant. Of the innocent forms, papilloma, either simple or multiple, occurred in 39%; fibroma, sessile or pedunculated, was next in frequency; cystic tumours were not nearly so common; and other forms, including myxoma, angeioma, adenoma, lipoma, and enchondroma, were rare. The period during which these tumours are most common is between the ages of 20 and 40 years, but they are also frequent during childhood.

[5] _Internat. Centralblatt fur Laryngol._, Jahrgang v u. vi, 1888-9, 'Die Frage des Ueberganges gutartiger Kehlkopfgeschwulste in bosartige, speciell nach intralaryngealen Operationen.'

Malignant growths occur at a later age, mostly between the ages of 40 and 60, and attack males more than females. Carcinoma is far more common than sarcoma, and is generally of the squamous-celled variety.

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