Viscoelastic properties of the superficial musculoaponeurotic system (SMAS): a microscopic and mechanical study.

A study was undertaken to determine the physical properties and microscopic structure of the superficial musculoaponeurotic system (SMAS) tissue. Forty virginal specimens and eight reoperated specimens were examined. The following findings were discovered.

Mechanical properties and microstructure of the superficial musculoaponeurotic system.

Because of the widespread reliance on SMAS tightening procedures in present-day face lift surgery, a study was undertaken to examine the physical properties and microscopic structure of both virginal (40 specimens) and reoperated (8 specimens) SMAS tissue. The findings could be of practical value to the surgeon and are reported herewith: First, the SMAS is a composite fibrofatty layer comprising collagen and elastic fibers interspersed with fat cells. Second, microscopic appearance shows a considerable amount of elastic fibers in close relationship to the collagen fibers.