[ Location ] Localized in the erect sitting position or supine position, at the midpoint lateral to the border of the ala nasi, in the nasolabila groove. (Fig. 17 )
 
[Regional Anatomy] Skin→subcutaneous tissue→levator muscle of the upper lip. Superficial layer, the branch of infraorbital nerves of maxillary nerve; deep layer, the gena branch of facial nerves, and branches or subordiantial ramus of the facial artery and vein.