An upper orbit or eye bag and a tear trough depression exacerbates the tired and senile appearance and is one of the most common eyelid aging signs. It is mainly caused by gradual atrophy and the inward sinking of periocular fats due to aging, followed by congenitally high eyebrow bones, and in some cases, it is induced by excess weight loss, staying up late, diseases (such as exophthalmia as a result of hyperthyroidism), or medication. Regardless of the cause, patients with early signs or mild symptoms undergo temporary filling by a nonsurgical method (such as the injection of hyaluronic acid), but for distinct symptoms or orbital depressions unable to be corrected by filler injection, autologous fat grafting should be considered to attain a relatively stable and prolonged improvement. At present, autologous fat grafting in periocular areas is available in the following two methods:

Fat injection

Similar to other facial fat transfers, the physician would first collect a proper amount of reusable fats from other body sites by liposuction and after the purification of the adipocytes, directly inject them into the orbital depression via an extremely thin facial injection tube (filling the sunken upper eyelid or tear-through groove of the lower eye pouch). The advantages of this surgery are its simple process, rapid recovery, and the absence of a scar, while the disadvantages are that it is difficult to accurately control the depth and quantity of the injection, which is prone to incur subcutaneous lumps or unevenness if applied at the thin area of the eyelids. Moreover, as infused fats are not stitched or fixated, some patients have complications such as fat globule dislocation that progresses to the eye pouch. Therefore, surgical indications should be strictly confirmed as not everyone is suitable to undergo such surgeries.

Fat grafts

Fat grafting is conducted by collecting intact adipocytes from the tommy and then emplacing adipose particles layer by layer into the eyelid depression via a surgical incision; this is therefore commonly combined with double eyelid or lower eye bag surgery. First, a 1-cm small incision is made at the umbilicus, and bulks of intact adipose particles are retrieved, rinsed, and selected; they are then directly emplaced at the depressed eye socket or tear-trough groove via the upper or lower eyelid external incision before the skin appears completely flat and smooth in appearance. Its advantages are that the quantity and depth of fat grafts are controlled by the physician during the operation via direct visual inspection and that fat grafts are less likely to result in subcutaneous lumps due to a difficult inaccurate injection dose in the fat injection. Besides, fat grafting garners more complete and undamaged adipocytes than other common liposuctions, so the adipose survival rate is relatively higher than that obtained by fat injection.