WILLIAMS' OPERATION AGAINST ROARING IN HORSES 355 



around the entire margin of the ventricle. The separation 

 of the mucous membrane now begins and attempt is made to 

 bring it out intact in the form of a sac. This is done by dis- 

 secting from above downward around the entire circumfer- 

 ence of the marginal incision previously made around the 

 ventricle. When the separation has proceeded some distance 

 it is continued and completed by blunt dissection with the 

 handle of the scalpel as the edges are simultaneously drawn 

 upon with forceps. 



The dissection of the mucous membrane from this deep 

 cavity, which extends in a disadvantageous direction, is sim- 

 plified by immediately sacrificing the vocal chord, but expe- 

 rience seems to indicate that this structure, in the interest of a 

 successful termination, should be invaded as little as possible. 



Fifth Step. — Dressing. — Accumulated blood is bailed 

 from the larynx and trachea and the wound is dusted moder- 

 ately with iodoform and protected against the aspiration of 

 litter into it while the patient is reviving from the anaes- 

 thetic, by wrapping the neck with a clean towel. 

 " ■ AFTER-CARE. — The external wound is washed daily 

 with an antiseptic solution and then dusted with iodoform 

 five per cent, and boric acid ninety-five per cent. In twenty 

 days the wound will have healed and the patient may be exer- 

 cised moderately and be returned to its usual work at the 

 end of thirty days. The cure from this operation is not in- 

 stantaneous; improvement comes slowly during the weeks 

 succeeding the convalescence. If, however, there is no im- 

 provement after two months, the operation may be consid- 

 ered a failure. 



SEQUELiE.— (I) Chronic inflammation of the laryngeal 

 cartilages, either local or general, is the only serious sequel 

 of the operation. This may manifest itself locally upon the 

 cricoid cartilage whose continuity was sacrificed to gain ad- 

 mission into the larynx, or it may attack the whole organ. In 

 either event it ends in stenosis that causes a roaring more for- 

 midable than the original. The cartilages become hard and 

 deformed and sometimes the whole organ undergoes a hyper- 

 trophy of the soft structures together with a. calcification of 

 the cartilages that ends fatally during the succeeding twenty- 

 four months. The prevention of this sequel seems impossible 

 although it is the author's opinion that the changes in the 

 cricoid cartilage can be prevented by more gentle use of the 

 retractors. The general affection is undoubtedly due to post- 

 operative infection, and hence is unavoidable. 



2. Pneumonia and bronchitis, which would seem to be 



