94 SURGICAL APPLIED ANATOMY. [Chap. vn. 



incision ; (2) in turning back the flap ; and (3) in sepa- 

 rating the bone. 



(1) The following are the parts cut in order from 

 above downwards in the usual, or " median," incision, 

 an incision commencing parallel with the lower 

 eyelid, and continued down the side of the nose, 

 round the ala, and through the middle of the upper 

 lip : Skin, superficial fascia, orbicularis palpebrarum, 

 palpebral branches of infraorbital nerve and artery, 

 lev. labii superioris, angular artery and vein, lev. 

 labii sup. alseque nasi, lateralis nasi artery and vein, 

 nasal branches of infraorbital nerve, compressor 

 iiaris, depressor alse nasi, attachment of nasal carti- 

 lage to bone, orbicularis oris, sup. coronary artery 

 and vein, and mucous membrane of lip. Various 

 branches of the facial nerve to the muscles may be 

 cut. (2) In turning back the flap, the muscles above 

 named will be dissected up, together with the tendo 

 oculi, the levator anguli, the buccinator, a few fibres 

 of the masseter, and, on the orbital plate, the inferior 

 oblique muscle. The infraorbital nerve and artery 

 will be cut as they leave their foramen. In the flap 

 itself will be the trunks of the facial artery and vein, 

 the transverse facial artery, and the facial part of the 

 facial nerve. (3) In separating the nasal process, the 

 lachrymal sac and infratrochlear nerve will be damaged, 

 and the nasal duct and external branch of the nasal 

 nerve cut across. In separating the bones below, 

 the coverings of the hard palate are divided, and the 

 attachment of the soft palate to the palate-bone, 

 unless the removal of that process can be avoided. 

 u Any attempt to dissect off and preserve the soft 

 covering of the hard palate is futile" (Heath). 

 Posteriorly, the trunk of the infraorbital nerve is 

 again divided (this time in front of Meckel's ganglion), 

 together with the posterior dental and infraorbital 

 arteries, and some branches of the spheric-palatine 



