turbances in the organ of hearing, as the pressure conditions in the endolymphatic and perilymphatic spaces, which depend on the hydrostatic pressure of the lymphatic fluid, tend to regulate each other mutually, and thus to prevent the occurrence of excessive pressure.

3. NERVOUS DISEASES WHICH PRODUCE DEFINITE ALTERATIONS IN THE NOSE, PHARYNX, AND LARYNX, AND IN THE EARS.

DISEASES OF THE SPINAL CORD.

Tabes Dorsalis.

The occurrence of laryngeal disturbances in tabes was formerly regarded as very rare, and until very recently opinions diverged as to the existence of any relation between tabes and difficult hearing. But now we have a long series of statistics and reported cases which prove that the vagus and auditory nerve are comparatively often involved in tabes dorsalis, if not quite as frequently as the optic nerve. According to Klippel,1 the olfactory nerve also becomes involved in tabes, and there result disturbances of the sense of smell, manifesting themselves in unilateral anosmia, parosmia, and hallucinations of scent.

Statistics differ very widely as to the frequency of laryngeal symptoms in tabes dorsalis; Krause found motor disturbances in 13 out of 38 cases, but does not give any detailed description of their nature; Marina, on the strength of Fano's investigation, gives 19 cases of motor disturbances in 36 patients suffering from tabes, in all of which the conditions were found to be abnormal. Dreyfus found two cases of double posticus paralysis among 22 tabes patients; Burger 2 in 6 out of 20 cases found that motor disturbance could be demonstrated with the laryngoscope. I may add that among 27 tabetic patients in the Medicinische Universitäts-Poliklinik in Leipzig I found no disturbances in the larynx; while, on the other hand, in the case of one tabetic patient who had sought medical advice on account of dyspnea I found a double posticus paralysis associated with paresis of the vocal cords. Statistics based on such small Arch. de Neurol.," 1897; see "Schm. Jahrb.," vol. CCLVII, p. 82. 2" Die laryngealen Störungen bei Tabes dorsalis," Leiden, 1891.

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material are, however, of very little value, as were shown by Semon, who found among the 12 first cases of tabes which he examined unilateral or bilateral posticus paralysis five times, whereas the next 30 cases did not yield a single laryngeal disturbance. Of more recent contributions we may mention that of Gerhardt,1 who found 17 paralyses in 122 tabetic patients, II of the posticus (5 bilateral, 4 the right posticus, 2 the left posticus), and 3 of the recurrent laryngeal nerve (1 bilateral, 2 unilateral on the right side). The 3 remaining cases consisted of paralysis of the posticus and thyroid muscles once, paralysis of the recurrent nerve of one. side and of the posticus nerve of the other side once, and 2 paralyses of the thyroid aryte.noid muscle. In 2 cases there were ataxic movements of the vocal cords; in 4 cases there were laryngeal crises. 2

Among 100 cases of tabes Semon found 8 unilateral posticus paralyses, 3 bilateral posticus paralyses, and 3 unilateral paralyses of the recurrent nerve.

The most frequent laryngeal complications consist in motor palsies of the laryngeal muscles. The typical tabetic palsy is that of the crico-arytenoideus posticus, either of one or of both sides. In Berger's table of 71 cases of tabetic laryngeal paralysis published up to 1891, there are 33 cases of unilateral paralysis of the posticus, in a few of which there was a coexistent paralysis of the internus; the remaining 38 cases consisted of unilateral paralysis of the posticus, while a few cases showed paralysis of the posticus on one side and paralysis of the recurrent nerve on the other.

From this it would appear that bilateral paralysis of the posticus is almost as frequent as the unilateral form. It must, however, be remembered that the symptoms due to the various forms of paralysis may either be so marked as to produce a very noticeable alteration in the voice or respiration, and thus arouse a suspicion of laryngeal disturbance, or they may be so mild as to escape the examiner's notice altogether, unless every tabetic patient is systematically subjected to a laryngoscopic examination. Hence, unilateral paralysis of the posticus, which does not affect phonation and respiration, is frequently overlooked, while bilateral paralysis of the abductors of the glottis never 1 Nothnagel's "Spec. Path. u. Ther.," vol. XIII, p. 55. Heymann's Handb.," vol. I, p. 705.

escapes detection, because it is always associated with hoarseness and dyspnea.

Complete paralysis of the recurrent nerve is extremely rare in tabes dorsalis. As we have previously stated, a subacute disease affecting the nuclei of the vagus and of the recurrent nerve first produces paralysis of the posticus, which only becomes converted into paralysis of the recurrent later in the disease. The question naturally suggests itself, Why do we not observe this transition from the median to the cadaveric position in those cases of tabes dorsalis which persist for many years, and which, as we know from the reports of autopsies, attack the nuclei in the medulla oblongata? The only clinical fact which points to a progressive nature of posticus paralysis is the occurrence of paresis of the internus, which manifests itself in the laryngeal image in relaxation of the vocal cord, and clinically in the hoarseness and a diminution of the dyspnea due to the bilateral paralysis; the rare cases of recurrent paralysis in tabes, being imperfectly described, are open to question, and can not be regarded as secondary to posticus paralysis. One thing is absolutely certain-the adductors or closers of the glottis are never affected alone in tabes dorsalis. The cricothyroid muscles are also practically never attacked; Gerhardt's case of paralysis of the cricothyroid associated with that of the posticus is the only one that we have met with. 1

The laryngeal palsies are usually observed in the earlier stages of tabes dorsalis and sometimes precede all other symptoms.

It has been occasionally stated that intermittent paralysis of the vocal cords may be observed in tabetic patients, and that a posticus paralysis may disappear after a few days and return after the lapse of weeks; but the statement has not been satisfactorily proven, and until we have more accurate observations we must assume that once the tabetic paralysis has developed in the larynx there is no hope of cure. The paralysis may, however, develop very gradually, and several cases have been reported which remained constantly under observation and in which a complete posticus paralysis developed in the course of weeks or months: at first there was some power of abducting the vocal cords;

1 " Ann. des mal, de l'oreille," 1891, p. 480.

this gradually diminished, and finally the vocal cords remained immovable in the median position.

The subjective symptoms are the same as those which occur in paralysis of the vocal cords from other causes. When there is hoarseness, a posticus paralysis produces no symptoms unless the vocal cords are implicated; any marked disturbances always tend to posticus paralysis. The symptoms consist in dyspnea, the voice being only slightly, if at all, affected. As the paralysis develops very gradually, the patient becomes accustomed to the stenotic condition of the rima glottidis, and the interference with respiration is comparatively slight, except during bodily exertion and phonation; during sleep, however, the stenosis becomes very marked. There is a good deal of inspiratory dyspnea, showing itself in loud, sighing inspirations, while the expiration is quite free. There is, of course, a constant danger of asphyxia whenever a greater demand is made on the respiration during any form of bodily activity, so that sooner or later tracheotomy becomes necessary in cases of posticus paralysis.

An experiment performed by Ruault deserves mention in this place. He excised 1.5 cm. from the recurrent nerve in a tabetic patient who was suffering from intense dyspnea due to posticus paralysis, in the hope of bringing the vocal cords into the cadaveric position, but the operation was not followed by any change either in the laryngeal image or in the subjective symptoms of the patient. This is the only case of its kind, and has no particular value.

Ataxia of the vocal cords is a name given to a condition in which the vocal cords execute irregular movements during phonation and deep respiration. Krause was the first to remark that the vocal cords tended to move in jerks and to stop midway between complete adduction and the inspiratory position, producing interrupted or scanning speech. It has been elaborately proved by Burger that this motor anomaly, which occurs exclusively in tabes, is a true ataxia, or disturbance in the coordination of all the antagonistic groups of muscles the cooperation of which is necessary to produce all the movements of the vocal cords.

Laryngeal crises consist in convulsive attacks of cough. and dyspnea, and occur in the beginning of, or during the course of tabes, like gastric crises. They differ from attacks of simple laryngeal spasm in that all the other respiratory

muscles are involved. The attacks either occur without any ascertainable cause or after slight external, mechanical, or psychic irritation, particularly swallowing and the introduction of a probe into the throat. According to Oppenheim, pressure on the throat at a point near the anterior border of the sternomastoid muscle at the level of the cricoid cartilage produced attacks of coughing. The attacks occur with variable frequency; they may be repeated several times within a few hours, or a single attack may be followed by a period of freedom lasting for months or years, or may never be repeated. They are usually preceded by a feeling of tickling or burning in the throat; this is followed by a choking attack, with loud, strident inspirations and short, puffing expirations, accompanied by a violent, barking cough which has been compared to whooping-cough. The patient becomes intensely excited and greatly terrified at the idea of impending suffocation, until, after a short time-the attacks rarely last longer than a minute-the respiration is suddenly or gradually restored, sometimes after the expectoration of a little mucus (Burger). They usually end in recovery in spite of their intensity, although Burger was able to collect five cases which terminated fatally during the attack.

Pharyngeal crises are described by Oppenheim as attacks of convulsive gulping movements, which, however, are foreign to our subject. Sensory disturbances of the larynx during tabes are rare. A few cases of anesthesia and hyperesthesia of the pharyngeal and laryngeal mucous membrane have been observed. With regard to the appearances produced by tabes dorsalis in the organ of hearing, I shall here reprint a paper which I read before the Deutsche Otologische Gesellschaft in Dresden, in 1897, and which appeared in a rather inaccessible portion of the reports of that meeting:

In spite of the fact that several papers have appeared on the subject of aural disturbances in tabes dorsalis, opinions are still divided as to their nature, and there are those who deny the occurrence of deafness as a result of tabes.

I shall omit the list of reported cases and shall not repeat the various opinions which have been expressed on this subject, contenting myself with referring to Burger,