FARADIZATION OF INTEENAL ORGANS. 99 



" I have repeatedly witnessed the same phenomenon myself, both in patients 

 and in healthy persons, and I have not been able to regard it as arising from 

 excitation of the recurrent, but only as the result of an impression upon the 

 larynx generally. I have seen this tremulous and uncertain condition of 

 the vocal cords chieiiy in sensitive and unpractised persons ; and in practised 

 persons also upon whom some unusual impression had been made upon the 

 larynx by cauterization, faradism, or galvanism, although the special nerves 

 and muscles of the organ had not been included in the circuit. 



" While, therefore, I cannot admit that the result above described is a 

 satisfactory test of successful excitation of the recurrent, I think that we 

 possess, in energetic detraction of the epiglottis, a certain sign of excitation 

 of the siTperior laryngeal. This phenomenon may sometimes be produced 

 from within, and chiefly from the pyriform sinus, which is crossed obliquely 

 by the internal branch of the superior laryngeal — sometimes running under 

 an elevation of the mucous membrane (plica nervi laryngii, HyrtL). 



" The reason why it is so seldom possible to excite the inferior laryngeal 

 nerves alone from the cutaneous surface may be found, I believe, in their 

 deep position, and in the layers of miiscle by which they are covered, and 

 which prevent, by their contraction, the pressing in of the electrode and the 

 penetration of the current. These layers are formed by the i^latysma, 

 the sterno-thyroid and sterno-hyoid, the omo-hyoid, the thyro pharyngeus, 

 and the crico-pharyngeus. The inaccessibility of the recurrent would also 

 often be due to the enlarged lateral portions of the thyroid body ; and the 

 adijiose tissue of the neck may also hinder the pushing in of the electrode 

 towards the deeper parts. 



" Although, therefore, it cannot be denied that, in particularly favourable 

 conditions, with a thin neck, a small thyroid body, and a platysma not 

 extending far forwards, it may be possible to isolate the laryngeal nerves 

 from the surface ; yet they generally, on account of their deep position, are 

 withdrawn from the reach of direct excitation, and any attempt to act upon 

 them, especially upon the recurrent, from the skin, must be regarded as a 

 highly doubtful procedure, not to be controlled by any satisfactory test of its 

 success. 



" We must, of course, fully admit that, by the i:)ercutaneous application of 

 electric currents, therapeutic results have been obtained in cases of paralysis 

 of the vocal cords, and in disorders of innervation of all kinds, especially in 

 hysterical subjects. The observations of Bamberger, Gerharclt, von Bruns, 

 Tobold, Meyer, and Benedict, place this beyond doubt. Such knowledge, 

 however, affords only an uncertain and deceptive basis, and does not assist 

 in the si:)ecial treatment of a diseased part, such as a single paralysed mi;scle, 

 or group of muscles, with currents of a known intensity. On the one hand, 

 we are quite uncertain whether the current will generally penetrate to the 

 pai'ts requiring excitation ; and, on the other, the complicated functions of 

 the recurrent nerve deprive us of the power of influencing, through its 

 means, determinate groups of muscles ; such as those that open or close the 

 glottis, or that render tense the vocal cords. 



" This deficiency of the percutaneous method has been perceived, of late 

 years, by others beside myself. Duchenne, Mackenzie, Gerhardt, and von 

 Bruns have all laid stress upon the possibility and necessity of direct elec- 

 trization of special portions from the pharynx. Dtichenne's observations lack 

 the laryngoscopic basis ; but the other authors named have employed the 

 mii-ror as a guide to the operating hand. Gerhardt and von Bruns alone 

 appear not to have gone beyond isolated experiments upon j^atients ; while 

 Mackenzie limits the direct action of the current to the vocal cords and the 

 arytsenoid cartilages, without having considered the complicated anatomical 

 relations, or the possibility of a detailed diagnosis, and of a localization of the 

 current corresponding thereto. 



" The greater number of specialists in the domains of laryngeal disease and 

 electro-therapeutics, as Tobold, Meyer, Benedict, and others, content them- 

 selves with the percutaneous method, on accoimt of the diflficulty of the 



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