The Lower Orbital Septum Revisited: A Three Dimensional Structure Determines Aesthetic Presentation and Impacts Operative Rejuvenation

Abstract Background The anatomic basis of lower eyelid bulging remains enigmatic and the concept of compartmentalization is often used to describe bulge location, but does not completely explain the cause of periorbital ageing. Objectives We aim to explore lower septal structure, including the concept of adipose tissue compartmentalization, and assess relevance to aesthetic presentation and operative rejuvenation. Methods The inferior orbital septae of 10 cadavers (20 lids) were dissected with magnification, with special attention to contiguous tissues such as orbital fat, orbicularis oculi muscle, tarsus, and inferior oblique muscle. The cadaveric specimens were 71-83 years old (mean = 75). Subsequent comparative observations were made in 63 consecutive patients undergoing lower lid blepharoplasty for eyelid distention. The age range was 35-82 years (mean = 63). Results Cadavers and patients both demonstrated a loose anterior membrane deep to the post-orbicular fascia and discrete, transverse ligamentous elements deep to the anterior membrane. In surgical patients, evaluation of the posterior adipose tissue space disclosed a posterior septal membrane that joined the anterior septal membrane at the superior transverse ligament, creating a discrete compartment isolating the adipose tissue from the eyelid protractors and retractors. Variation in the gross fibrous characteristics of septal constituents was observed in both cadavers and operative patients and this accounted for observed patterns of clinical presentation. Conclusions Lower lid topography is predictive of the fibrous character of the underlying septal components and topography is useful for surgical planning.