New applications for botulinum toxin

October 18, 2008

Las Vegas - As injection techniques and aesthetic applications for Botox (botulinum toxin A, Allergan) expand, knowing the facial anatomy and tempering patient expectations remain critical to success, an expert says.

Las Vegas

- As injection techniques and aesthetic applications for Botox (botulinum toxin A, Allergan) expand, knowing the facial anatomy and tempering patient expectations remain critical to success, an expert says.

"The most important aspect of botulinum toxin usage is understanding the yin and yang of the face. That means that when you relax one muscle, you allow for hyperactivity of another," says Susan H. Weinkle, M.D., a Bradenton, Fla., dermatologist in private practice.

Accordingly, she says dermatologists must have a map of the facial muscles "indelibly imprinted" on their minds. Along with knowing which muscles to target, she says, one also must document preoperative concerns such as redundant skin.

"Dermatologists must not offer unrealistic expectations," or patients will return, she adds. Other botulinum toxin "don'ts" include creating a mask-like appearance and cheating by using too few units or over-diluting.

Regarding injection tips, Dr. Weinkle says she favors a 1 cc BD syringe because it has a projecting piece that extends into the hub of the syringe, thereby avoiding waste. For the glabellar area, she recommends injecting intramuscularly at a 90 degree angle.

More importantly, she says that if one massages above the brow area after injection, "You will push that botulinum toxin over the orbital rim and give the patient an eyelid ptosis."

Conversely, she says one can gently massage the procerus injection in the mid-glabellar region and disperse the toxin into the depressor supercilii, thereby achieving an effective medial depression of the brow. Moreover, she says dermatologists who don't treat the lateral corrugator are "missing the boat." Combining botulinum toxin injections with fillers such as hyaluronic acid also helps maximize results, Dr. Weinkle tells Dermatology Times.

When injecting the forehead, "make the person move dynamically so you can see the muscles and choose appropriate locations."

One also must remember that botulinum toxin will diffuse 1 to 3 cc cm, which means injecting too low on the forehead could cause brow ptosis, Dr. Weinkle says.

For injecting crow’s feet, she says the feathering technique represents the newest wrinkle. In addition to assessing patients dynamically pre-injection, "I do my crow’s feet injections intradermally."Injecting deeply into the muscle only increases bruising, she says.

Furthermore, "patients really hate zygomatic cheek lines from that occur when they smile and the cheek goes up." Although injecting this area is potentially dangerous, Dr. Weinkle says that diluting botulinum toxin and using the feathering technique help ensure safe, effective treatments.DT

Disclosure: Dr. Weinkle is a consultant for Allergan, Dermik/Sanofi-Aventis, Galderma, BioForm, Medicis and various other manufacturers of injectable dermatologic products.