Collections of Pus in the Guttural Pouches. 97 



A second mode of operating is by external incision. For this 

 purpose are wanted scissors, knife, artery forceps, iron probe bent 

 in the form of the letter S, and a tape. The horse having been 

 thrown and fastened and the head extended, the hair is removed 

 from a surface in front of the prominent border of the first bone 

 of the neck, and an incision made between this border and the 

 parotid gland. The incision is made immediately beneath a 

 tendon which may be felt as a flattened cord crossing the border 

 of the bone in its upper third, audit should be carried downward 

 one and a half inches parallel to the margin of the bone. In this 

 preliminary stage the operator has to carefully avoid injury to the 

 parotid gland and the posterior auricular artery and vein. The 

 skin and fascia having been divided the index finger of the left 

 hand is pushed inward and forward until the prominent angle of 

 the large cornu of the hyoid bone is felt, together with the 

 muscle (stylo- hyoid) inserted into this bone above the angle 

 referred to. The next step is important, since crossing on the 

 inner side of this muscle and bone at their point of union is the 

 (internal carotid) artery which becomes subsequently enveloped 

 in a fold of the membranous wall of the guttural pouch. The 

 slightest variation in the position of the artery may here prove 

 fatal unless the greatest caution is used. With the knife guarded 

 by the index finger of the right hand the muscle is cut through 

 from behind forward and the pulsation of the artery felt for be- 

 neath. Avoiding its position the knife, with its cutting edge 

 turned forward and its point directed toward the horse's nose, is 

 pushed through the walls of the sac. The curved probe is now 

 introduced and carried downward until it is felt beneath the skin 

 just behind the angle of the lower jaw. This may be safely cut 

 down upon with the knife as important parts (vessels and nerves) 

 have been turned aside by its pressure. A tape attached to the 

 probe is now drawn through the pouch and retained by a knot on 

 each end. Tepid water must be injected through the lower orifice 

 daily for three weeks, astringent antiseptic injections thrown in 

 occasionally and the horse fed from the ground. At the end of 

 this period the tape may be removed, and the wounds allowed to 

 heal. During the course of treatment it is always advisable to 

 change the tape several times by cutting the knot off one end of 

 the old one, stitching the new one to it and drawing it through. 



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