Preventive and Curative Treatment. 137 



- ■ So long ago as 1834, Giinther, of Hanover, from a care- 

 ful study of the alterations observed in the larynges of 

 affected horses, ventured to attempt relief to them by 

 operating directly or indirectly on the larynx, but without 

 success.i He and his son, K. Giinther, again instituted ex- 

 periments in 1845, upon affected and healthy horses, with the 

 view of testing the feasibility of removing the obstruction in 

 that organ, so as to allow the passage of a larger volume of air 

 through it. Operating through the trachea, at first both 

 vocal cords were removed in horses that roared, but the result 

 was negative. Then the vocal cord of the affected side was 

 extirpated, but the Roaring was not diminished, but rather 

 increased — owing, it is supposed, to the retraction caused 

 by cicatrization, which drew the aryt?enoid cartilage deeper 

 into the larynx. Trial was made of passing a seton through 

 the laryngeal sac, but this^ failed; then the experiment was 

 made of removing the vocal cord and the laryngeal sac, as 

 it was believed that the latter also hindered the admission 

 of air ; but here, again, the success was nil. The entire 

 aryt^enoid cartilage was then excised, but all the horses 

 died, through food and water passing into the trachea 

 and lungs. Better results, . in some instances, followed 

 excision of the anterior part of the aryt?enoid carti- 

 lages {processus vocalis) and its vocal cord, great im- 

 provement being noted ; but in other instances the defect 

 was aggravated, in consequence of cicatricial contrac- 

 tions. When very severely exerted, however, though the 

 horses roared, there were no signs of asphyxia. One 

 horse was rendered much worse, because of caries and dis- 

 tortion of the cartilage. Finally, they endeavoured to 

 hring about a firm adhesion between the inner surface of 

 the thyroid and the outer surface of the arytaenoid cartilage, 

 by excising the laryngeal sac, but leaving the vocal cord 

 intact. Here, again, the result was uncertain ; for while in 



1 "Die Topographische Myologie des Pferdes,"' etc. Hanover, 1886. 



