37<l OPENING THE GUTTURAL POUCHES. 



The following method, which consists in opening successively the 

 superior and inferior parts of the guttural pouch, is probably the best. 

 It is at first like Chabert's, but the cutaneous incision is carried a 

 little further, extending over the lower edge of the wing of the atlas. 

 The cutaneous incision having been made, the hinder edge of the 

 parotid gland is gently raised and pushed forward, and between the 

 long horn of the hyoid bone in front, and the styloid process of the 

 occipital behind, the subparotidean fascia is cut through, bringing into 

 view the occipito-hyoideus and digastricus muscles. The two fore- 

 fingers dilacerate the connective tissue, and the angular space (occupied 

 by the occipito-hyoideus) between the styloid of the occipital and the 

 hyoid cornu is discovered. At the centre of this space, a straight 

 bistoury, with its cutting edge turned towards the hyoid bone, is 

 passed obliquely downwards and forwards through the muscle into 

 the guttural pouch. The knife having just penetrated the pouch, is 

 withdrawn, and the puncture is then enlarged by a sharp thrust of 

 the index finger. If the knife is directed towards the ear or atlas, 

 it may wound the facial nerve, posterior auricular artery, internal 

 carotid, or the nerves that accompany it ; if towards the larynx, 

 the hypoglossal nerve and external carotid artery will be endangered. 

 Deep puncture is also dangerous, for if the knife is implanted per- 

 pendicularly it may reach the internal carotid artery, vagus and 

 accessory spinal nerves. 



Counter opening. To pass a gauze or rubber drain through the 

 guttural pouch, a counter opening must be made and preferably in 

 Viborg's triangle. For this purpose Dieterich employed a curved 

 trocar ; but the operation may be more easily managed with an S-shaped 

 probe, or a blunt seton needle passed through the upper wound into 

 the pouch and directed towards Viborg's triangle, the counter opening 

 being made over the point of the probe. The rubber, tape, or gauze 

 drain is then drawn into position, and the ends are tied together 

 over the parotid gland. 



The further treatment consists in flushing the pouch with disinfect- 

 ants and astringents, after removing the contents. Too much fluid 

 should be avoided, as it may enter the pharynx, trachea, or lungs by 

 way of the Eustachian opening. Degive lost a horse in this way from 

 a solution of potash entering the lungs and producing pneumonia. 



The method just described no doubt deserves preference ; it 

 lessens the danger of injuring large vessels or nerves, and insures 

 complete evacuation of the pouch. Following Dieterich's directions, 

 Moller succeeded in passing his hand into the guttural pouch, and 

 examining from this point the Eustachian tube. 



