i6o Vetermary Medicine. 



In cases due to distortion of the larynx from tight reining the 

 bearing reins should be dispensed with or rearranged so as to en- 

 courage protrusion of the nose, and the horse should be bitted to 

 the side chains or straps in the stall several hours daily so that 

 the head shall be elevated and the nose protruded. 



When roaring depends on paralysis of the laryngeal muscles, a 

 mode of palliation may be adopted as practised by the London 

 omnibus and cab men. A strap is fixed round the nose supported 

 by a strap passing down the middle of the face and the cheek 

 piece of the bridle on each side and buckled beneath the chin. 

 On the inner side of this strap where it passes over the false nos- 

 trils is attached on each side a semiovoid pad which presses on 

 the flap of the nostril and regulates the entrance of air. The 

 principle on which it acts will be understood when we consider 

 that the paralyzed cartilage is drawn into the passage by the rush 

 of air and that the closure of the channel is more complete and 

 the roaring more marked in proportion to the force of the current. 

 The pads by lessening and regulating the rush of air into the 

 lungs thus leave the passage in reality more open and largely 

 obviate the difficulty of breathing and the noise. 



In extreme cases with the structural lesion in the head, throat, 

 or upper two-thirds of the neck relief may be secured by trache- 

 otomy. 



A more radical operation is that introduced by Giinther for the 

 excision of the left arytenoid cartilage. As improved by Moller 

 and others this consists in an incision through the cricoid cartilage 

 and crico- thyroid membrane (or even the first rings of the trachea) 

 and the complete extirpation of the left arytenoid cartilage and 

 left vocal cord. The manipulations belong to surgery. The re- 

 sult is satisfactory in removing the violent dyspnoea in hurried 

 breathing and in very favorable cases in obviating noise alto- 

 gether though not permanently. More commonly some stridor 

 remains but not enough to interfere with pace or with heavy 

 draft. From my personal experience in performing the opera- 

 tion, I would recommend it in all cases in which the obstruction 

 is so great as to interfere with the use of the horse on the track, 

 or road, or for heavy draught. But in slight cases, in which the 

 disease causes little or no inconvenience beside the noise, I would 

 advise some less radical measure. 



