The adoption of dermal fillers for age related volume replacement has contributed to the surge in aesthetic patients. As patients become more savvy, it becomes obvious that filler outcomes are dependent primarily on the provider and not the brand of the filler injected. Somewhere between 80-90% of the fillers used are based on Hyaluronic Acid, a naturally occurring substance found throughout the skin, and joints. (It is an interesting side note that the structure of HA is similar throughout all species.) One of the attractive qualities of HA is that there is an “antidote”, an enzyme called hyaluronidase, which can dissolve HA based dermal fillers.
There are several versions of hyaluronidase available in the US. There are animal based products such as Vitrase (ovine based), Hydase (bovine), and Amphadase (bovine). The one product, Hylenex, is actually a recombinant form of the human hyaluronidase. There is some risk of allergic reaction to the animal based products but not Hylenex (author’s preferred choice). The intended use of hyaluronidase is to allow for increased tissue permeability, thereby allowing for greater dispersion and delivery of products injected. It is also used when hyperosmolar fluids extravasate into the skin and in improving uptake of radiopaque solutions in the bladder. The primary reason it is used in aesthetics is to dissolve HA filler.
The reasons to dissolve HA filler are:
- Poorly placed filler giving an aesthetically poor result
- Where too much filler was placed
- Filler that is infected
- Filler is forming a granuloma
- Filler is causing ischemia/vascular occlusion
- Filler is causing visual changes or blindness
The are more and more fillers being introduced to the market each year. Each one has it’s own characteristics and nuances when injecting. There are also, many new injectors entering the industry daily. It is fair to say that the number of poor outcomes and complications is inevitably going to rise. Unfortunately, trainings are not being done for the indications and administration of hyaluronidase. It is beyond comprehension that there are many offices, I dare say, a majority, who either don’t normally have any or adequate doses of hyaluronidase.
It is absolutely imperative that a facility that injects HA fillers stock at least 1000 units of hyaluronidase. Doses of 400 units or more need to be injected in areas of vascular occlusion immediately to achieve optimal outcomes. If no response, additional doses need to be injected. If an ophthalmologic complication occurs, at least 1000 units needs to be injected immediately to have any chance for recovery of vision. Even with doses in the thousands of units, there should be no concern regarding loss of naturally occurring hyaluronic acid as it will replaced by the body’s normal regenerative process over 24-48 hours.
Unfortunately, the majority of providers have little or no experience with hyaluronidase and/or have none available in their facilities. It is beyond comprehension the lack of preparedness for not only reversing poor outcomes, but in resolving medical emergencies. The industry must rise up to educate about complication identification and treatment protocols. Poor outcomes and complications affect the entire aesthetics field and not just the individuals involved.