The cause:
As a person ages the eyebrows descend. This happens most near the outer third of the eyebrow. The reason for this is that the muscles of the forehead exert most of their action on the inner two thirds of the eyebrow leaving the muscles that pull the eyebrow down to have no opposition near the outer portion of the brow. When a person undergoes aging in the area, their lateral brows become descended which imparts a tired look to their face. In addition to these changes to the outer eyebrow, all aspects of the face are held together by ligaments which keep the face looking young. Secondarily due to the effects of gravity and loss of muscle tone, the whole eyebrow can descend when the ligaments which hold the eyebrow against the brow bone weaken and loosen. This explains the descent of the eyebrow as a whole. These same loosening effects also can be found in the eyelid. The eyelid is held in place by ligaments that are attached to the brow bone and the muscles that open the eyelid. When they are weakened and loosened the eyelid crease can be less distinct, the fat held back by the ligaments can pouch out and the result is further external effects that can impart a tired look. These same ligaments can also lead to the descent of the eyelid margin so that the eyes become smaller. From a functional standpoint, the loose eyebrows, eyelid skin and eyelid margins can impede a persons vision giving certain people a functional reason to search for a treatment. |