Botox is now the most well known injectable cosmetic facial treatment and is phenomenally effective at reducing undesired lines of facial expression, particularly in the forehead and eye area. The temporary paralysis effect of Botox works by reducing muscle pull on the overlying skin. Since lines and wrinkles form on the face from the pull of muscle that runs perpendicular to the line or wrinkle, this provides a strategy for where to place Botox injections. In the glabellar frown wrinkles, which are the number one facial area for Botox injections and the facial area from which the initial clinical studies for FDA approval were done, injection into the brow depressors (corrugator and procerus msucles are the main ones) is an effective approach.
Coincidentally, and with a simultaneous positive aesthetic result, paralysis of the brow depressors leaves the brow elevator muscles unopposed. In so doing, a minor brow lift is obtained in many patients. As the eyebrows are elevated by the vertical-running frontalis muscle, the lack of any down pull by the depressors allows this muscle to raise the eyebrows to some degree. Multiple clinical studies have shown that modest brow elevation occurs in the range of 1 to 3mms. This may sound like a modest amount, but in the face this can be a make a real observable difference.
Brow elevation with Botox can be done for the inner brow, outer brow, or both. It all depends on where one places the injections. As the most common area for Botox injections is in the glabellar area, only an inner brow lift will result. To create a more complete eyebrow lift, the outer brow depressors must be paralyzed as well. This means injecting out on the side of the brow to weaken the downward pull of the orbicularis oculi muscle. Injecting both inner and outer brows can create a ‘chemical’ brow lift which appears within seven days after the injections.
I have found that brow lifting with botox works best in female patients who do not have thick forehead skin or heavy brow tissue. It seems to be less effective in males although this probably dose-related as it is well known that larger muscles needs higher doses of Botox to be effective.
Dr. Barry Eppley
Indianapolis, Indiana