causes pyemic metastases, especially in the joints and lungs; less often in other viscera.

395. At the beginning the symptoms of sinus thrombosis are not very distinct. They are merely the exaggeration of the disturbances produced by a severe mastoid process. Headache is rarely absent, and especially prominent when the thrombosis is started by a subdural abscess. Malaise and gastric disturbances may be due to the mastoid disease alone. The characteristic symptom, however, is fever. Whenever the fever of an acute otitis does not cease within a few days, except in children; whenever it increases suddenly or steadily; and especially when fever sets in in chronic afebrile cases, sinus thrombosis should be at once suspected. Chills alternating with extensive fluctuations in temperature establish the diagnosis; yet there are occasionally rare exceptions to this rule. Tenderness, edema, or inflammatory swelling over the site of the sinus are not constant, but very suggestive symptoms.

If the thrombosis extends into the jugular vein, this is often indicated by perceptible hardness and tenderness of the vein, sometimes with inflammatory edema of the tissues of the neck. This condition must not be confused with perforation of a mastoid abscess through the internal surface of the tip.

The absorption of septic poisons is indicated only by the general systemic disturbances, including enlargement of the spleen and sometimes jaundice. Pyemic metastases, however, produce unmistakable symptoms. If they occur in the joints, the latter become tender and swollen. In the lungs the pyemic emboli are revealed by the occurrence of sudden irritation and cough, and if superficial enough, they can be detected by dulness and râles. The clinical picture may be complicated by the coexistence of a serous meningitis with the symptoms peculiar to it.

With rare exceptions sinus thrombosis is fatal unless treated surgically. The earlier the operation, the greater

the chances of recovery. Even in unselected cases the mortality is not over 50 per cent., and very much smaller when all unnecessary delay is avoided. If only metastases into the joint have occurred, the prognosis is still fair; more serious, however, in the case of pulmonary embolism. In any case operation should be attempted.

396. According to the existing indications, the operation should either be the simple chiseling into the mastoid or the radical clearing of mastoid antrum and tympanic attic. The sinus is then to be laid bare by working upward and backward from the antrum, using small rongeur forceps as much as possible in preference to the chisel. When the indications are clear for incision into the sinus, the latter should be exposed to the utmost extent-3 to 4 cm. or even a trifle more. Whether the operation should include opening of the sinus or not must be judged by the following criteria: If the symptoms are relatively mild and the sinus wall is not discolored, and the sinus is still felt by the probe to be a channel containing fluid blood, it may be let alone after completely removing all diseased bone and exposing the sinus wall. The incision into the sinus may not add to the danger of the operation, but, on account of hemorrhage, it complicates the after-management. If the septicemic symptoms do not abate in the course of one to two days, the sinus may be opened at the next dressing without the necessity of narcosis. But in the case of pronounced pyemic symptoms or even in the absence of the latter when the sinus is discolored or gangrenous it should be included in the operation. Even when the venous wall shows little change, it may be found that the severe systemic symptoms present are due to the septic breaking down of the clot. The puncture of the sinus by means of a hollow needle is not a reliable diagnostic method, as it neither reveals a small parietal clot nor any small accumulation of pus which it does not happen to strike, while it does involve the danger of infection of the dura if the needle happens to perforate the

inner sinus wall. The opening of a sinus begun with scissors may be finished with a bistoury on the grooved director. The broken-down clot should be scooped out until a solid thrombus is reached, and toward the rear even until the blood begins to flow. It is best to excise the infected part of the sinus wall. Before the sinus is

opened the operation on the bone or on any existing subdural abscess should be completed, because hemorrhage may enforce a rapid interruption of further operation. It can, however, be always checked by compression with gauze.

Opinions are divided as to the advisability of ligating the jugular vein. Its exposure adds to the shock of an otherwise necessarily long operation (one to two hours). It is also said that ligation of the vein is neither an absolute preventive of pyemia nor necessary in every instance of jugular thrombosis. Yet experience has shown that the danger of pyemia is certainly diminished by eliminating a menacing clot in the jugular vein. When jugular phlebitis can be recognized, it is best to begin the operation by an extensive exposure of that vein in the neck. It should then be ligated below in the apparently healthy part, and upward as close as possible to the jugular bulb, and the intervening portion excised, with ligation of the internal facial vein. If the exposure of the lateral and sigmoid sinus shows thrombosis extending to the jugular bulb, many good operators deem it best to ligate the jugular vein in the neck before proceeding to clear out the sinus.

CHAPTER XLVI.

DISEASES OF THE INTERNAL EAR.

397. The labyrinth is found diseased in about 5 to 8 per cent. of ear patients. The differential diagnosis between lesions of the labyrinth and those of the middle. ear can usually be made with certainty, but it is often impossible to distinguish between affections of the internal ear and those of the auditory nerve, except by the history and other concomitant symptoms. Since the labyrinth is the organ of both the sense of hearing and of the static sense, its disease may cause symptoms referable to either or both. On account of their velemence the disturbances of the static sense are apt to predominate in the clinical scene. Dizziness may vary from a mere sense of unsteadiness to a feeling of passive rotation or falling. It is relieved by rest in bed, but may even then be distressing. When severe, the dizziness is apt to lead to nausea and to vomiting. It may also reveal itself by nystagmus-like swinging movements of the eyes, generally of slow rhythm. Vertigo necessarily interferes with steady gait. There may be incoordination of movements. In pronounced instances the sufferer steadies his walk by spreading the legs. The dizziness is apt to last as long as the lesion in the semicircular canals is of an irritative character. When it begins to decline, it is apt to fluctuate in severity with periodic intensification. In most instances the dizziness ceases ultimately. The patient learns to control his movements with the correlated aid of the other senses, so that finally he gets along fairly well under ordinary circumstances. But when the eyes are closed, the unsteadiness reappears. After extensive disease of the semicircular canals all unusual movements requiring

fine coordination-for instance, standing on one leg or balancing become difficult or impossible.

398. The hearing may be but moderately damaged, or it may be entirely abolished. Absolute deafness is a positive proof of labyrinthine disease, except when due to destruction of the auditory nerve. It is characteristic of labyrinthine lesions that the perception of high tones is lost first. The failure to hear the highest notes of the Galton whistle proves disease of the internal ear. If the deafness is not absolute, it may be often found that there are small "islands" in the auditory range for which perception is still retained, with a defect for the greater part of the scale. Tuning-fork tests show that bone-conduction is reduced to the same extent as airconduction. The Rinné test is always positive, never negative. The time of perception of the tuning-fork placed on the skull is reduced in proportion to the deafness. In Weber's test the sound of the tuning-fork is referred to the better ear if the affection is not symmetric. When labyrinthine disease is complicated by middle-ear lesions, all tuning-fork tests become indecisive. In such cases dependence must be placed mainly on the loss of the high tones and on the history.

Another symptom of cochlear involvement is diplacusis. A musicaily trained ear hears certain or even all tones accompanied by another note one-half to one tone higher or lower in pitch. As a rule, diplacusis is due to hearing the "false" note in the affected ear, with normal perception in the other, but it may also be due to "double" hearing in the diseased ear. Still diplacusis is very rare in purely labyrinthine affections. This symptom, infrequent at best, is oftener met with in slight exudative catarrh of the middle ear, denoting, nevertheless, a labyrinthine complication, usually of a very transient character. Tinnitus is complained of in all affections of the internal ear, except when the auditory nerve-ends are totally destroyed. There is nothing about the noises which distinguishes them from those heard in