DISEASES OF THE LARYNX 507 



by introducing into it a piece of india-rubber tubing and keeping the 

 patient tied up by the head. The subsequent injections can then be 

 made through the tubing. 



DISEASES OF THE LARYNX 



Diseases of the larynx more especially involve the mucous membrane 

 by which it is lined. Of these the more common are: (1) Laryngitis or 

 inflammation; (2) ulceration; (3) oedema or effusive swelling. In addition, 

 it is also liable to disorder of the nerves, by which its movements are 

 regulated. These neurotic disturbances are represented by (a) paralysis, 

 (b) spasm. Morbid growths, in the form of tumours or polypi, are also 

 now and again accountable for laryngeal trouble. 



Laryngitis, or inflammation of the larynx, although by no means a 

 common disorder in the horse, is nevertheless of serious import when it 

 assumes a severe or acute character. In some instances it proves rapidly 

 fatal, as the result of asphyxia or suffocation following upon swelling of 

 the inflamed membrane and consequent narrowing of the breathing aperture. 

 In others it runs a less acute course, and when the disease subsides leaves 

 behind a more or less lingering irritation, attended with chronic cough, 

 and maybe difficulty of breathing. 



Causes. Laryngitis is more especially seen in stabled animals, and 

 frequently results from exposure to cold and wet after severe exertion, or 

 from sudden changes of temperature in animals occupying hot, badly- 

 ventilated stables. It may also arise out of a common cold, or may appear 

 in the course of an attack of influenza, or strangles, or as the result of 

 the specific poison of glanders, or purpura hsemorrhagica. Operations on 

 the larynx for roaring are sometimes followed by it, and we have known 

 it to be induced by the lodgment of foreign substances in the laryngeal 

 cavity. Air charged with irritating vapours is also capable of exciting 

 laryngitis in susceptible subjects. 



Symptoms. The symptoms of the disease will vary with the severity 

 of the attack. When it arises out of cold, it is commonly preceded by 

 the ordinary symptoms of that ailment. Usually its onset is marked by 

 general indications of illness, evinced by slight dulness, impaired appetite, 

 increase in the body temperature, quickened pulse, and maybe more or 

 less soreness of the throat. Where no such premonitory symptoms appear 

 the disease is ushered in by a severe and painful cough, which comes on 

 in paroxysms. In character the cough is harsh and coarse, and the painful 

 nature of the act is denoted by the effort which the patient appears to 

 make to suppress it, and the restlessness and excitement it induces. Pres- 



