Brush up on anatomy to avoid filler complications

To avoid possible vascular compromise or vascular complications associated with the injection of fillers, injectors should re-acquaint themselves with facial anatomy and practice cadaveric dissection, according to Jack Kolenda M.D., FRCSC, Chief of the Department of Otolaryngology at the Trafalgar Hospital in Oakville, Ontario, Canada. Dr. Kolenda recently spoke at the 12th annual meeting of the Canadian Association of Aesthetic Medicine (CAAM) (April 2016, Toronto, Canada).

Describing the danger zones when injecting fillers and the potential complications, Dr. Kolenda, an otolaryngologist practicing in facial plastic surgery, offered methods to avoid complications such as necrosis and even blindness. "The face is like a landmine," Dr. Kolenda told meeting attendees. "There are some areas that are more dangerous and others that are less dangerous. There is always a risk [of a complication]. It is remote, but you want to minimize the risk."

One of the ways to sidestep facial complications is to fine-tune knowledge of facial anatomy, says Dr. Kolenda. "We take anatomy (in medical school), but it may be such a long time since we took it," he says in an interview with Dermatology Times.  "We forget how vascular the area is [that is being injected]. If you can take a cadaveric course to remind yourself where the vessels lie, that will improve your technique. You will then visualize [the vessels] when you are doing the injections. You will know what technique you should be using. I really think knowledge of the anatomy and doing cadaveric dissection makes you a safer injector."

One unfortunate trend that Dr. Kolenda has observed is seeing patients who have been injected with products with which he is not familiar. "Some patients are ordering products through the Internet," he says.

Of related interest: Techniques for preventing filler complications

Next: Considerations for previously treated patients

Previous treatment matters

It is important that healthcare professionals who are injecting fillers be cognizant that previous use of fillers and surgery elevates the risk of complications, says Dr. Kolenda. "To a certain degree, everyone's anatomy is different," he says. "The anatomy has changed if rhinoplasty has been performed, for example, and if fillers have been injected. If fillers have been injected [in the past], patients will develop fibrosis. Some fillers lead to more scar tissue than other fillers."

Dr. Kolenda differentiated between arterial compromise and venous compromise. "It is important to recognize [arterial compromise]," he says. "Patients complain about pain right away [with arterial compromise]. Venous compromise is late presentation and will develop in tissues over time. It is important to have your patient leave with an instruction sheet and make sure you call the patient and follow up."

The effects of fillers can vary. Generally, with temporary fillers, an effect such as a bruise is temporary, but "you can get a bad complication," says Dr. Kolenda.

The degree to which injection pressure is applied also influences the risk of complications, as does the speed with which filler is injected, says Dr. Kolenda.

"The less pressure you apply, the less risk there is of intravascular injury," says Dr. Kolenda. "The greater the pressure you apply, the greater risk there is of intravascular injury. In addition, the slower you go with injection, the better things will go (and there will be fewer complications)."

The onus is on the injector to provide informed consent and indicate all possible complications that can occur with injection of fillers. While it is a rare complication, blindness can occur with injection of a hyaluronic acid (HA) filler. There have been 89 documented cases of blindness reported globally in the literature related to injection of HA fillers.

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Next: How to avoid cannula complications

Cannulas not foolproof

Clinicians should not regard cannulas as foolproof, and should be aware that their use can present risks as well, particularly when thinner cannulas are used.

"The thinner the cannulas are, the more they behave like needles," says Dr. Kolenda. "If you are using a thin cannula, and there is scar tissue present and you are applying pressure to advance the cannula, you can perforate an artery or vein. You can cause an embolic event with a cannula."

Some zones of the face, such as the infra-orbital area or the supra-orbital area, are zones where it would be preferable not to use a needle when injecting filler, says Dr. Kolenda, adding that it is advisable to use lidocaine when injecting around the eyes.

Injection of neurotoxins can precede injections of fillers in the glabella and offers a means of decreasing the amount of filler that needs to be injected, explains Dr. Kolenda. "Use a neurotoxin to relax everything, so the amount of filler you inject can be limited," he advises.

When injecting a neurotoxin to treat crow's feet, be cautious about the zygomatus major, says Dr. Kolenda, specifying,"don't go too deep (when you inject), as this will cause a crooked smile."

Dr. Kolenda says that, because the arterial system is highly complex, serious side effects can occur with filler injection. "The arterial system is interconnected just like a highway system," says Dr. Kolenda. "In reported cases of blindness due to filler injections, concurrent strokes have been documented."

Some patients experience minor complications after filler injections, such as cold sores. Evidence has suggested that prophylactic use of medicine like acyclovir prior to filler injections is advisable.¹

Dr. Kolenda advises that injectors have emergency kits on hand and have ready access to hyaluronidase to correct any errors with hyaluronic acid.

Also read: Top 5 dermatology controversies

Dr. Kolenda reports no relevant financial disclosures.

References:

1. Duffy DM. Complications of fillers: overview. Dermatol Surg. 2005;31(11 Pt 2):1626-33.