Various techniques are used to address tear trough deformities, and though procedures are largely successful, complications can occur, one of the most severe of which can be a vascular occlusion that causes blindness.
The face is a very vascular region, and because injections are "blind," there is always the possibility of an intravascular injection, regardless of which area of the face the physician injects. If a filler is inadvertently injected into an artery, the product could travel in a retrograde fashion and then blood flow can push the filler along another vessel branch that can result in complications. This is called embolia cutis medicamentosa, or Nicolau syndrome.
Tear troughs may also be complicated by bruising, since the orbicularis muscle is very vascular, and damage to a very small vessel can cause a frustrating bruise.
"I like to place my gel fillers a little bit more superficial, but I still try to stay under the orbicularis oculi muscle. Instead of injecting right into the depth of the tear trough, I usually make my needle puncture lower on the cheek and then carefully ride the orbital rim up to the tear trough. By placing the needle entry about half an inch below the tear trough, I have seen much less bruising in my patients, and thankfully, less adverse events on a whole," says Joe Niamtu III, D.M.D., F.A.A.C.S., a board-certified oral and maxillofacial surgeon with a practice limited to cosmetic facial surgery in Richmond, Va. "Also, as the tear trough area is a bound-down tissue, carefully injecting at the periosteum as well as in a more superficial plane could help to aesthetically fill out the area much better."
Some physicians may prefer to deposit their fillers while the needle is pushing through the tissue, because this technique creates a pathway for the filler. Others may prefer to inject while withdrawing, as this may less likely result in intravascular injection of product. Aspiration just prior to injecting is another technique that could also help avoid intravascular injection, but this technique is not fail-proof.
Many physicians are now beginning to introduce fillers through blunt-tipped cannulas instead of needles in the hopes that the cannulas will not damage or enter a vessel. According to Dr. Woodward, physicians should refrain from injecting a bolus of filler and then expect to massage the area and spread the product, as this could also increase the risk of complications.
"I think it is really hard to say which technique (anterograde versus retrograde injection) is best, as there is not enough data to support either technique as ideal," Dr. Woodward says. "I prefer to inject while withdrawing a 30-gauge needle along the periosteum with a slight wiggling motion to evenly distribute the filler because I believe it would be more difficult to have an intravascular incident with this style. However, some believe that smaller needles can more easily enter a vessel.
"Regardless of the needle used, it is very important to take your time, inject slowly and keep the needle moving. A still needle inside a vessel with a bolus injected would be the most likely scenario for an embolic event."
According to Dr. Woodward, one way to help avoid visible nodules as well as an embolism is to stop injecting after withdrawing the needle about two-thirds of the way from the targeted tissue, as one can better avoid introducing filler to any vessel in the orbicularis.