Most dermatologists are well aware of the danger of damaging nerves during cold-steel surgery, but may be less aware of the danger zones involved in filler injection, said Dr. Howard K. Steinman at a cosmetic dermatology seminar sponsored by Skin Disease Education Foundation in Santa Monica, Calif.
"Unlike the risk with a scalpel, where you're going to damage a nerve, the risk with fillers is that you may compress or occlude an artery," Dr. Steinman said in an interview. "You will get necrosis and scarring and disfigurement."
Dr. Howard K. Steinman
Dr. Steinman, director of dermatologic and skin cancer surgery at Texas A&M College of Medicine in College Station, offered some tips for avoiding the problem and suggestions on what to do if an occlusion occurs.
"The one everybody knows about from all the way back to the days of collagen is in the glabella," he said. If collagen is injected into the frown line, it is possible to damage the supratrochlear artery. If compressed or occluded, this artery can get a band-like area of damage extending up the forehead.
A second danger zone is at the nasolabial fold, where the angular artery runs close to the surface. Interrupting the blood flow here can cause damage to skin at the nasolabial fold and the side and tip of the nose. Although this is a relatively rare complication, the nasolabial fold is a popular site for filler injections, and physicians need to be mindful of this side effect, Dr. Steinman noted.
The third danger zone comes at the lips, where injections can interrupt flow in the labial artery.
In all cases, the symptoms are similar: There will be blanching, erythema, or edema, followed by necrosis unless the occlusion is treated promptly.
To avoid occlusion, he recommended injecting the filler perpendicular to the direction of the artery and remaining superficial but also pointed out that an artery can be indirectly occluded. According to one theory, simply injecting too much filler can compress the artery to the point of interrupting the flow.
Occlusions and compressions should be treated as soon as detected. The first step is an aggressive tapping and massaging of the area to try to break up the mass, Dr. Steinman said.
If that does not work, and the filler being used is hyaluronic acid-based, the next step is an injection of hyaluronidase, an enzyme that dissolves hyaluronic acid.
A third possibility is to apply nitroglycerin paste to the skin directly above the affected area. Typically used to keep the arteries dilated, the paste can improve flow in the case of occlusion or compression.
Unfortunately, the symptoms of an occluded artery do not always become evident immediately. "In some cases the patient won't notice this for hours after you have done the procedure," Dr. Steinman said. "They'll call you and they'll say, 'I'm having a problem.' You can certainly have them tap and massage as soon as possible, but you should meet them, even if it's at night, and start this protocol as soon as practical. It's not something you want to ignore. 'I'll see you in the morning,' is not the correct option for this."
Dr. Steinman stated that he had no conflicts of interest to disclose. SDEF and this news organization are owned by Elsevier.