Landmarks Medical and Surgical

by Luther Holden; James Shuter

THE FACE.

8. The approaches to the organs of the senses, their ever-varying expression, their numerous muscles, and their rich profusion of vessels and nerves, give the face great anatomical importance, which has a most valuable bearing, not only on the practice of surgery, but on the physiognomy of health, and in the diagnosis of disease.

9. Foramina for branches of fifth nerve.—As a surgeon may be called upon to divide any one of the three chief branches of the fifth nerve upon the face, he looks with interest to the precise situations where they leave their bony foramina with their corresponding arteries. The supraorbital notch or foramen can be felt about the junction of the inner with the middle third of the supraorbital margin. From this point a perpendicular line drawn with a slight inclination outwards, so as to cross the interval between the two bicuspid teeth in both jaws, passes over the infraorbital and the mental foramina. The direction of these two lower foramina looks towards the angle of the nose.

10. Pulley for superior oblique muscle.—By pressing the thumb beneath the internal angular process of the frontal bone, the cartilaginous pulley for the tendon of the superior oblique muscle can be distinctly felt. We should be careful not to interfere with this pulley in any operation about the orbit.

11. Lower jaw.—The working of the condyle of the jaw vertically and from side to side can be distinctly felt in front of the ear. When the mouth is opened wide, the condyle advances out of the glenoid cavity on to the eminentia articularis, and returns into its socket when the mouth is shut. The muscle which causes this advance is the external pterygoid; and it gives the jaw a greater freedom of grinding motion.

The posterior margin of the ramus of the lower jaw corresponds with a line drawn from the condyle to the angle. In opening abscesses in the parotid region, the knife should not be introduced behind this line for fear of wounding the external carotid artery. Punctures to any depth may be safely made in front of it. They are often necessary where inflammation of the parotid gland ensues after eruptive fevers, and runs on to suppuration. The swelling, tension, and pain are most distressing. Owing to the fibrous framework of the gland, the matter is not circumscribed, but diffused. One puncture is not enough. Three or more may be requisite. The blade of the knife should be held horizontally, so as to be less likely to injure the branches of the facial nerve. We are not to be disappointed if no matter flows. The punctures give relief, and matter will probably exude the next day.

12. Parotid duct.—A line drawn from the bottom of the lobe of the ear to midway between the nose and the mouth gives the course of the parotid duct. Opposite the second upper molar, the duct opens by a papilla into the mouth. The branch of the facial nerve which supplies the buccinator runs with the duct.

13. Temporal and facial arteries.—The pulsation of the trunk of the temporal artery can be felt, between the root of the zygoma and the ear. This should be well known to and used by chloroformists. It is also a convenient pulse to feel in a sleeping patient. The facial artery can be distinctly felt as it passes over the body of the jaw at the anterior edge of the masseter; again near the corner of the mouth close to the mucous membrane: and, lastly, by the side of the ala nasi, up to the inner side of the tendo oculi. By holding the lips between the finger and thumb the coronary arteries are felt under the mucous membrane. The facial vein does not accompany the tortuous artery, but runs a straight course from the inner angle of the eye to the front border of the masseter, just behind the artery.

14. Eyelids and eyes.—The opening between the eyelids varies in size in different persons; hence more of the eyeball is seen in some than in others, and the eye appears larger. Although human eyes do vary a little in size, yet the actual difference is by no means so great as is generally supposed. The size of the fissure has much to do with the apparent size of the eye. Contrast the narrow fissure of the Chinese and Mongolian races, and the apparent smallness of their eyes with those of Europeans. As a rule the external angle of the lid is higher than the internal. When not exaggerated, it gives the face an arch and pleasing expression.

Evert the lids to see the Meibomian glands; observe their perpendicular arrangement, in the substance of the tarsal cartilages.