332 VETERlftARV SURGICAL OPERATIONS 



thetic has been administered, harness restraint may answer, 

 but always with much less satisfaction than with the table, 

 which brings the field into an accessible position. 

 INSTRUMENTS REQUIRED.— 

 i. Scalpel. 



2. Probe-pointed curved bistoury. 



3. A number of artery forceps. 



4. A large tumor grappling forceps. 



5. Firing irons and forge. 



6. Needles and thread. 



7. Gauze or cotton packing. 



The firing irons are not absolutely essential, although 

 they are the author's preference to effect a safe hsemostasis. 

 The thermocautery, in lieu of the irons, will be found help- 

 ful in partially controlling the flow of blood from the numer- 

 ous spurting vessels. 



TECHNIQUE.— First Step.— Preparation of the Field. 

 — As the field is generally in a filthy state this step may be 

 advantageously executed before the animal is cast. The 

 forelock, mane, and" the hairs covering the poll are trimmed, 

 wellwashed, shaved, and then submitted to a good cleansing. 

 The fistulse are squeezed to evacuate as much pus as possi- 

 ble, and superficial abscesses are lanced and irrigated. 



Second Step. — Incision. — The incision overlaps the crest 

 of the occiput anteriorly and extends backwards as far as the 

 spine of the dentata. It is almost twelve inches long in the 

 ordinary sized horse, and parallels the median line on the 

 uppermost side. The incision, if made from one-.half to 

 three-quarters of an inch above (the horse lying) the median 

 line, is still within the area of mane hairs and will therefore 

 leave no visible scar, and furthermore it is handier to oper- 

 ate above the median line than below it, or even directly 

 along its course. The incision is at once carried to the depth 

 of about two inches or more along its whole course through 

 the thick tissue that underlies the mane and the new-formed 

 connective tissue that generally accompanies poll-evil. The 

 knife should almost touch the atlas in. the middle ; it should 

 overlap the level of the inferior surface of the ligament an- 

 teriorly at the occipital crest, but posteriorly the exposed 

 position of the spinal cord in the atlo-axoid may be respected 

 by a gradual, diminishing depth. 



Third Step. — Arrest of Haemorrhage. — Already a co- 

 pious flow of b'ood from numerous vessels will have been 

 provoked, and as the vessels spurt from hard sclerotic walls 

 which prevent successful use of the forceps, actual cautery 



