Botulinum Toxin 2012: Applying the Data Into Clinical Practice Part 2
Joel Cohen, MD
Upper Face: “The Big 3”
Botox, Dysport, and Xeomin are all FDA approved for glabellar lines. The products are also used for the forehead and crow’s feet.
Dangers
Dermatologists should be cautious of the dangers associated with delivering fillers and toxins simultaneously.
Dosing
Data suggest that higher botulinum toxin type A doses resulted in greater efficacy and longer duration of the effect. In 2008, experts developed a consensus with regards to how to best achieve an optimal, relaxed and natural outcome using botulinum toxin type A. This resulted in basically cutting the forehead doses in half.
Dermatologists should also understand gender differences that exist in upper face musculature. In a 1998 cadaver study by Dr Macdonald, et al, males were shown to have greater corrugator thickness at both the medial canthus and mid-pupil regions versus females. An understanding of these anatomic differences can facilitate proper injection technique.
Potency
Dr. Cohen indicates that he does not think physicians should be desperately trying to find the right conversion ratio between products. He feels that the reality is that each of these products is it’s own neuromodulator. As such, he indicates, that if we decide to use that specific neuromodulator, then we should know that neuromodulator independently—and thus how to specifically use that product.
Dueling
Patient satisfaction is a key aspect of facial aesthetics. Various studies have looked at patient reported outcomes among the products available; however, it is often difficult to compare the results.
Duration
Across the board, looking at the glabellar lines, the duration of botulinum toxin type A is about four months. Data has also demonstrated that patients tend to have a cumulative effect; in that, the efficacy is stretched out over a longer period of time.
Delivery
Drs. Richard Glogau, Fred Brandt and others have begun to research topically applied botulinum toxin type A for the treatment of primary axillary hyperhidrosis as well as lateral canthal rhytid studies. Results have shown that topically applied BTX-A appears to be safe and effective.
Revance, a California-based company, has developed a proprietary platform that enables transcutaneous flux. The Revance technology works by employing two complementary and distinct pathways that are both present in human skin:
The first pathway is energy independent and therefore can occur in non-living cells. like the stratum corneum. It could also occur in living cells. The second pathway is energy dependent and only occurs across living cells.
Devices
Myoscience is currently investigating a hand-held cryotherapy medical device for the treatment of facial wrinkles between the brow, forehead lines and crow’s feet. It has shown promising results in difficult patients, i.e., complete treatment of dynamic horizontal forehead lines, constant brow position, immediate onset, and it proves to be a potentially new option for toxin-averse patients. The device uses a 27-30-gauge needle placed near motor nerves that innervate frontalis muscle.
Summary
It is important that dermatologists convey the message that botulinum toxin type A has been studied and BTX injections can be beneficial for patients who want to delay the outward appearance of aging, for patients who believe their faces are not communicating their emotions properly and/or for patients who simply want to look their best.