LIGATION OF THE PAROTID DUCT. 45 



there is felt a resistant cord, the external maxillary artery 

 about 3 mm. in diameter, pulsating in the living animal. 

 Between this and the oral border of the masseter muscle make 

 an incision about 4 cm. long parallel with the artery through 

 the skin and skin muscle. This incision is more readily 

 made by gathering up a fold of skin about 2 cm. high and 

 cutting through this. Pick up the loose connective tissue 

 with a pair of forceps and excise it. Immediately behind 

 the external maxillary artery, a, Figs. I and II, Plate VIII, 

 is the external maxillary vein v and behind this and immedi- 

 ately on the border of the masseter muscle lies the parotid 

 duct, st. In case ot' salivary calculi which cannot be re- 

 moved through the mouth and cystic dilation of the par- 

 otid duct, make the cutaneous incision at the affected 

 point, open the parotid duct, and after the removal of the 

 calculus, etc., close the duct wound by means of intestinal 

 sutures in such a way that the external surfaces of the lips 

 of the wound in the wall of the duct are brought in contact, 

 or ligate the duct on the proximal side of the point of opera- 

 tion. Legation is accomplished by passing a strong silk 

 thread behind the duct by means of a curved needle carry- 

 ing it around the duct and tying with a surgeon's knot. 

 The parotid duct can also be previously split and an internal 

 wound made at the point of ligation. Close the skin wound 

 by means of a continuous suture and cover the operative 

 surface with iodoform collodion or with wound gelatine. 



