One of the typical features of an aging upper face are a variety of skin lines that develop between the eyebrows. The action of specific muscles combined with the effects of gravity create an abnormal skin pattern of vertical, oblique, and horizontal lines. These dynamic and eventual static wrinkles are bothersome for many patients as they create the emotional impressions of anger, grief, and age.
The non-surgical use of Botox injections and the surgical approach of browlifting or foreheadplasty are proven methods of modifying these muscles. By changing the degree or amount that these muscles move, the upper face becomes more relaxed and more youthful.
The corrugator muscle is the main culprit in this indesireable set of glabellar facial expressions. The horizontal portion of this muscle is responsible for pulling the eyebrows inward. When done enough over time, an evident pair of vertical skin creases develop. Known as the ‘11s’, they may also infrequently appear as a single large vertical crease. These vertical lines always extend significantly above the height of the eyebrows.
The oblique glabellar skin lines occur just at the level of the eyebrows, are oriented obliquely, and careful inspection will reveal they are not part of the vertical skin lines. They are caused by the medial eyebrow depressors which consist of the oblique head of the corrugators, the depressor supercilii, and the medial fibers of the orbicularis oculi muscles.
The skin crease that sits below the eyebrows is horizontal and is often called the ‘bunny line’. It is caused by the procerus muscle which pulls down the inner eyebrows. It creates this crease as it pushes down against the more fixed skin of the nose.
The combination of these six muscles flexing over time etches this pattern of glabellar lines between the eyebrows. In essence, dynamic wrinkles eventually become static lines if unchecked. This makes a good argument as to the benefit of early use of Botox or Dysport when one first begins to see this skin pattern appears. Such chemical prophylaxis is effective and many younger women today are embarking on this approach.
In established and deeper glabellar wrinkles, Botox and Dysport injections will make them more shallow but will not make them go completely away. In some cases, injectable fillers must be combined with muscle relaxation injections to make for a nearly complete smooth and wrinkle-free area between the eyebrows.
If one is seeking a more permanent or longer-term treatment, this is where the option of a surgical foreheadplasty comes in. Besides altering the shape and position of the eyebrows, this operation is intended to help lessen these unfavorable glabellar skin lines. This is done by weakening the actions of the aforementioned six muscles through removal or excision of some of these muscles. This is best done through an open incision (coronal or hairline browlift) but good and diligent endoscopic techniques can make a dent in their action also.
Most patients, regardless of their degree of glabellar skin lines, begins with injection therapy to see how much improvement they can achieve. In advanced cases associated with excess upper eyelid skin, the combination of a browlift and blepharoplasty can make for a satisfying forehead result.
Barry L. Eppley, M.D., D.M.D.
Indianapolis, Indiana