458 VETERINARY SURGICAL OPERATIONS 



subsequent collar friction. The hypertrophied zone will con- 

 tract into a smaller body and the denuded zone will re-cover 

 with epithelium, if adequate protection against pressure is 

 provided or if the patient is given complete rest for several 

 months, but as soon as work is resumed the same condition 

 recurs until finally it becomes permanent. 



This lesion, although by no means painful to pressure, 

 requires prompt surgical intervention to prevent it from in- 

 creasing into a larger and larger growth that will require 

 an interference of proportionately greater magnitude, with 

 possible permanent deformation of the collar seat. 



Technique of Ablation by Dissection.— After washing, 

 shaving and disinfecting the growth and its surroundings, an 

 elliptical incision that includes within its outlines the denuded 

 zone and adjacent scar tissue is made across the growth 

 from above downward. The > incision should overlap 

 superiorly and inferiorly, better to expose the growth for 

 dissection. The island thus isolated is then grasped and 

 drawn upon firmly with strong grappling forceps as the skin 

 is carefully dissected back on both sides to the shoulder level. 

 The skin flaps are now drawn apart with tenacula and the 

 forceps transferred to the uppermost part of the growth, 

 whence ablation is effected by a downward dissection. When 

 ■completed, if properly done, the bottom of the wound should 

 be smooth and free from any part of the hypertrophied tissues. 



After a few moments' waiting for the appearance of bleed- 

 ing vessels which might require attention, the wound is closed 

 with two sets of sutures:— (ist) quilled or mattress sutures 

 loosely set one inch from the edges, and (2nd) closely ar- 

 ranged interrupted sutures along the margin. An orifice 

 which is wadded with gauze is provided inferiorly for drain- 

 age and the suture line is painted with collodion. An hour 

 or two after the wound has been sutured the blood clot, if 

 any has accumulated, is squeezed out and the wadding re-ap- 

 plied into the orifice. 



The wound heals by primary union and the patient is 

 ready for the collar at the end of twenty-five days. 



The operation is performed in the standing position with 

 the aid of stocks, or preferably in the recumbent position. 

 Effectual cocainization is, on account of the extent of the 

 invasion, quite impractical. 



Weber's Method.— After cleansing the field as above the 

 ecraseur is passed over the growth, skin and all, and tightened 

 so as to severely tax the strength of its chain. The skin 

 around the entire peduncle is now incised through and 



