Friday, December 8, 2023
As an organization accredited by the ACCME, Medscape, LLC, requires everyone who is in a position to control the content of an education activity to disclose all relevant financial relationships with any commercial interest. The ACCME defines "relevant financial relationships" as financial relationships in any amount, occurring within the past 12 months, including financial relationships of a spouse or life partner, that could create a conflict of interest.
Medscape, LLC, encourages Authors to identify investigational products or off-label uses of products regulated by the US Food and Drug Administration, at first mention and where appropriate in the content.
Founder and Director, Dermatology, Cosmetic & Laser Surgery, Rockville, Maryland, and Fairfax, Virginia
processing....
Posted: 03/10/2011
Botulinum neurotoxin type A products for aesthetic use are approved by the US Food and Drug Administration for the temporary improvement in the appearance of moderate to severe glabellar lines associated with procerus and corrugator muscle activity in adult patients younger than 65 years of age. Other uses, such as brow shaping, are off label.
Can neurotoxins be used for eyebrow shaping?
|
|
Hema Sundaram, MD
Founder and Director, Dermatology, Cosmetic & Laser Surgery, Rockville Maryland, and Fairfax, Virginia |
Shaping of the eyebrows with botulinum neurotoxin type A (BoNT-A) is a fascinating procedure that requires an understanding of the complex interplay between the muscles that elevate and depress the brows. Brow shaping with BoNT-A is invariably performed in conjunction with treatment of other facial zones, such as the forehead; therefore, the results of this procedure should be viewed in the overall context of the facial recontouring that can be achieved through the skilled use of BoNT-A pan-facially.
When formulating a strategy for brow shaping, one must keep in mind that the ideal brow shape for women differs markedly from the ideal for men. The ideal eyebrow in a woman has a gentle curve, with the lateral three fourths of its length lying above the orbital rim. In contrast, the ideal male brow lies at or below the orbital rim for its whole length, appearing as a straight line. If BoNT-A injection causes the lateral aspects of a woman's brows to be lowered closer to the orbital rim, the effect is somewhat masculinizing; conversely, raising the resting position of a man's brows may have a feminizing effect.
The lateral brow depressor is the superolateral portion of the orbicularis oculi muscle, which lies below the lateral one third of the eyebrow. Injection of a small dose of BoNT-A at a single point into this lateral brow depressor weakens it and allows the lateral portion of the eyebrow to be raised by the unweakened frontalis muscle, which spans the forehead and serves as a brow elevator. It is advisable to palpate the superolateral portion of the orbicularis oculi in animation (frowning) to identify the point at which BoNT-A should be injected because eyebrow position varies considerably, especially in women because of tweezing.
The medial brow depressors comprise the procerus muscle, corrugator supercilii, depressor supercilii muscles, and the medial portion of the orbicularis oculi muscle. These muscles are commonly targeted for brow shaping via the injection of a small dose of BoNT-A into the region of the procerus. Weakening of the medial brow depressors allows the now relatively unopposed frontalis muscle to elevate the medial portion of the eyebrow.
The strategy for brow arching when treating the forehead with BoNT-A can be readily assimilated with this understanding of how the frontalis muscle acts in opposition to the lateral and medial brow depressors. Smaller doses of BoNT-A are injected higher on the forehead into the portion of frontalis that lies over the middle one third of the brow, causing relatively little weakening of the frontalis muscle thus resulting in little or no lowering of the brow here. Larger doses of BoNT-A are injected lower down on the forehead into the portion of frontalis that lies over the medial and lateral one third of the brows, causing greater weakening of the frontalis muscle and thus greater lowering of the brow here due to the action of the relatively unopposed medial and lateral brow depressors.
To avoid excessive brow elevation or arching, low doses of BoNT-A should be used during the initial treatment. Further BoNT-A can be injected, if needed, at follow-up 3 or 4 weeks later. This author has found that doses as small as 2.5 Dysport® Units (abobotulinumtoxinA, Medicis Pharmaceutical Corporation; Scottsdale, Arizona) or 1 Botox®Unit (onabotulinumtoxinA; Allergan, Inc; Irvine, California) to the superolateral orbicularis oculi suffice in many patients to produce aesthetically pleasing and natural-looking results.
Supported by an independent educational grant from Medicis Pharmaceutical Corporation.
