Vascularized membranes determine the anatomical boundaries of the subcutaneous fat compartments

PURPOSE: The subcutaneous tissue of the human body has been described as being arranged in anatomical units or compartments. Distinct compartments have now been identified on the face, trunk, and extremities. Septal boundaries have been noted on histologic evaluation. Despite these observations, a unifying explanation for the compartmentalization of adipose tissue has not been presented. METHODS: Twenty hemifacial cadaver specimens were obtained from the University of Texas Southwestern Willed Body Program. In 10 hemifaces, latex injection of the common carotid arteries was performed in conjunction with dye injection of fat to identify perforator vessels and source vessels associated with each compartment. The radiologic characteristics of the vascular network were further evaluated in 10 additional hemifaces using three-dimensional computed tomographic scanning. A lead oxide/gelatin mixture was injected into the common carotid arteries, and iodinated contrast was injected directly into the fat compartment. RESULTS: The perforator blood supply to the skin runs with, and is stabilized by, condensations of fascia. Each anatomical compartment evaluated in this study was associated with an identifiable artery or vein. Three-dimensional computed tomography after intravenous contrast injection confirmed the arrangement of perforator vessels running in the septal boundaries of each subcutaneous fat compartment. CONCLUSIONS: The subcutaneous tissue of the human body is partitioned by fibrous membranes that carry the perforator blood supply to the skin. Each anatomical compartment studied has an identifiable vessel that runs along its boundary. This interlocking connective tissue network provides stability and protection for the vascular supply to the face during facial animation. The anatomical arrangement of the subcutaneous tissues of the face and their associated vasculature is therefore highly organized, and could be related to the embryologic development of the facial musculature. This anatomical construct is applicable to the adipofascial tissues throughout the human body.