The sentinel fat pads: The relationship of the ROOF and SOOF to the temporal nerve in facial rejuvenation

Background: A great number of studies have reported on the temporal branch anatomy and its relationship to the fascial layers and various fat pads of the temporal region, but no article has included information on the relationship of the temporal nerve to the retro-orbicularis oculi fat (ROOF) and/or the suborbicularis oculi fat (SOOF). Objectives: The authors report the results of a series of human cadaver temporal nerve dissections, with particular attention paid to its relation to the ROOF and the SOOF. The results of a literature review and a subsequent open browlift are also reported to confirm the results of the cadaver study. Methods: Dissection was performed on 15 fresh human cadavers, for a total of 29 hemifaces. The course and relationships of the temporal nerve branch to the fascia, fat pads, and landmarks in the temporal region were noted and detailed. A thorough review was also performed for 23 articles, to compare the author's anatomical findings with data in the previous literature. Results: During cadaver dissection, the temporal branch was found to lie on the undersurface of the superficial temporal fascia. In the supraorbital area, the ROOF existed in the loose areolar plane or deep layer of the superficial temporal fascia, with the temporal nerve branch directly superficial to it. The temporal branch passed lateral to the SOOF in its superiomedial course at the level of the zygoma. These findings were later confirmed during an in vivo open browlift as well. Conclusions: The ROOF was formerly unrecognized as an important sentinel marker for possible injury to the temporal nerve branch during browlift. However, this cadaver study and its accompanying literature comparisons show that browlift dissection, whether endoscopic or open, should aim to keep the ROOF fat in the superficial plane, ensuring that the nerve branch is safe from iatrogenic injury.