Most young Asian eyelids are noticeably fuller than their Occidental counterparts due to an abundance of fat in the lid and surrounding structures.

Most of the added volume is provided by the orbital fat (yellow) that extends further downward in the Asian lid and the sub-brow fat (green) that is larger in size and also lower in position.

It is now appreciated that the most dominant factor in facial aging is a gradual loss of fat. Such change is first noted during the early thirties and then progresses at a variable rate based primarily upon genetics.

Unfortunately, fat loss in the eyelid and surrounding structures (collectively known as the "periorbita") is more noticeable at earlier ages in many Asian patients.

It seems as if the more fat there is to start with, the more fat there is to lose. As fat loss increases, the skin deflates. A growing concavity appears midway between the brow and eyelid and then gradually begins to deepen.

Since younger Asian lids are generally fuller while many older lids are noticeably hollowed, the net effect of this fat loss is to make the face appear prematurely old.

By the age of forty (but sometimes as early as the late twenties), advancing eyelid fat loss can become a source of real cosmetic concern.

• In advanced stages, the depth of the hollow may "pull in" so much skin that an objectionable depression (sometimes confused with a high crease) becomes the dominant facial feature.

Without ample fat, however, a true crease cannot exist. Instead, this depression signifies only a progressive collapse of the overlying skin and muscle against a hollowed interior.