The anatomy of suborbicularis fat: Implications for periorbital rejuvenation

Background: Periorbital rejuvenation has increasingly relied on augmentation with fillers. Numerous techniques have been described, including augmentation of the sub-orbicularis oculi fat. Cadaver studies initiated 2 years ago yielded presumptive evidence that sub-orbicularis oculi fat consists of two distinct regions. Knowledge of this anatomy is important for precision in facial rejuvenation. Methods: A pilot study was performed with radiopaque dye injection into the sub-orbicularis oculi fat and computed tomographic evaluation with three-dimensional reconstruction. Eight hemifacial fresh cadaver dissections were then performed with a modified dye injection technique to isolate regions of sub-orbicularis oculi fat and periorbital fat. The relationship of suborbicularis fat to deep cheek fat was observed. Results: This study confirms the presence of two distinct regions of sub-orbicularis oculi fat. A medial component extends along the orbital rim from the medial limbus to the lateral canthus. A lateral component extends from the lateral canthus to the temporal fat pad. The lateral component terminated superiorly at the lateral orbital thickening. Deep cheek fat abutted the medial sub-orbicularis oculi fat, thus creating a deep fat system in continuity across the face of the maxilla and along the orbital rim. Conclusions: This anatomy helps to define midface adipose tissue as a system of superficial and deep fat, of which medial and lateral sub-orbicularis oculi fat are a part. A working hypothesis of facial aging continues with the concept that loss and/or ptosis of deep fat compartments leads to changes in shape and contour. Folds, in contrast, occur at transition points between thick and thinner superficial fat compartments. These anatomical observations further the goal of site-specific augmentation and facial rejuvenation.