Lower-face Botox an exacting discipline

New Orleans - Botulinum toxin treatments in the lower third of the face and the neck require caution because these areas offer far less forgiving terrain than does the glabellar complex.

"Many practitioners are becoming more comfortable treating the upper third of the face. As our expertise evolves, we're starting to address the musculature in the lower part of the face," says Seth L. Matarasso, M.D., clinical professor of dermatology, University of California San Francisco School of Medicine.

For treating this area, Dr. Matarasso offers several key caveats:

In the upper face, complications rarely go beyond esthetic issues. In the lower face, they can impact the patient functionally.

"Most of the time in the lower face, Botox (Allergan) is used as adjunctive therapy, used in combination with fillers and/or resurfacing. It is not monotherapy. It is used in conjunction with other facial rejuvenating procedures," Dr. Matarasso says.

Lower-face use still less common

To date, lower-face applications for botulinum toxin - which currently holds U.S. Food and Drug Administration approval only for treating the glabellar complex - remain in the minority. Based on an unpublished retrospective review of patients he treated in 2003 and 2004, Dr. Matarasso estimates that 80 percent of his botulinum toxin procedures involve the standard upper-face areas - the glabella, the forehead and crow's feet.

Below the zygomatic arch, he typically treats the nasalis muscle by injecting three sites with three to five units each.

"That weakens the nasalis muscle and gets rid of the bunny lines," Dr. Matarasso says. "One must be very careful in this area, because I have seen people who've gone too far laterally and hit the levator labii superioris alaeque nasi (LLSAN). If you paralyze or weaken that muscle group, you can get a lip droop."

A dual approach

As with the nasalis muscle, practitioners and patients are growing more comfortable with botulinum toxin treatments for the orbicularis oris.

"Oftentimes," he says, "patients will have a resurfacing procedure or a filler put in for the lipstick lines that radiate from the mouth. But a lot of times, these lines stem from underlying hypertrophy of the orbicularis oris muscle. So an effective treatment is to place a very small amount of botulinum toxin into this muscle. I will inject right at the vermilion border, and I will have the patient purse their lips. Usually it's approximately four to six units for the upper lip, and the same amount for the lower lip, one unit per quadrant. That will soften these lines."

Here, too, Dr. Matarasso cautions against overly aggressive treatments, which will impair patients' ability to purse their lips, sip liquids, and pronounce the letters P and B.

"When it is done well," he says, "this procedure provides a very nice esthetic result because it relaxes the sphincter muscle of the mouth and gives a bit of pseudoreversion to the upper lip. And I find that combining fillers and Botox gives what I would consider a home-run result. A filler will address some of the fine static lines, and the botulinum toxin will get some of the more dynamic lines."