WHAT IS SMAS AND HOW IS IT RELEVANT TO FACELIFT SURGERY?
Our faces are such an important part of a sense of identity and self. It is natural that when it comes to considering rejuvenation surgery specifically facelift surgery, that we do as much research as possible. Inevitably we will come across the term Superficial Musculo-Aponeurotic System (SMAS). Often however, there is very little explanation about what this is and how it relates to facelift surgery.
Rudimentary facelift surgery was being performed in the early part of the 20th-century extending well into the 1970s with pure undermining of the skin, pulling the skin back, suturing it into place and excising the excess amount left. These skin-based facial rejuvenation and facelift surgeries, did not have outcome longevity. Skin by its very nature accommodates stretch and over time, in matter of months the effects of the initial surgery had been lost. Moreover, serial exertions of the skin resulted in the ears being pulled lower into the face and the air tunnel appearance.
Our improved anatomical understanding of the facial anatomy helped usher in a new year in facial rejuvenation and facelift surgery. The most fundamental change in this paradigm was the recognition that the SMAS layer network of fine muscles of facial expression and related fascia were fundamental to the ultimate appearance of the face. Furthermore, the relationship of the facial nerve, which provides motor innovation to these muscles and their overlying SMAS was increasingly defined. It became evident that manipulation of the SMAS, would yield a longer lasting facial rejuvenation and facelift results. The increased level of anatomical understanding allowed us to perform this surgery with relative safety in skilled hands.
All the variations of SMAS -based surgeries are effectively variations of what is called deep plane facelift surgery. The exceptions being SMAS plication and excision surgery techniques which strictly speaking do not enter the deep plane where facial nerve injury is more likely. In future blogs we will discuss these techniques and the pros and cons of each.