The risks of Hyaluronidase enzyme to reverse filler
After they have had the hyaluronic acid filler, they sometimes decide they do not like it or possibly it has not been done in the correct way for their face and they want to have it reversed.
Hyaluronidase enzyme is well known for its use in melting or reversing Hyaluronate fillers that are dermal fillers to help volumise the face. With that said, it is always good to point out the benefits and the risks of any treatment, particularly when that treatment is on the face or around the eyes.
Dermal fillers are often used in the under eye area for dark circles or hollows under the eyes. We also use them for depressions across the cheek, around the mouth and even in the temples.However, patients might not realise what the filler is going to look like on them.
Hyaluronic acid can be reversed by Hyaluronidase enzyme
The Hyaluronidase enzyme catalyses a degradation of hyaluronic acid (HA). It works very quickly on the injected hyaluronic acid based fillers.It can have side effects and these include:
- A probable minimal and temporary effect on your own lateral hyaluronic acid, which then re-grows post the Hyaluronidase injection.
- A return to the normal pre-hyaluronic acid face and periorbital area with a consequent return of the dark circles under the eyes or hollows in the cheeks.
- Discomfort and swelling immediately following the Hyaluronidase, which can last for two or three days.
- An immediate allergic reaction to the injection with immediate redness and swelling, which can precipitate a more generalised allergic response if not detected and treated rapidly.
Injecting Hyaluronidase, although a commonly performed treatment for over-correction or misplacement of hyaluronic acid does carry the above risks and the patients often do not realise that it is a medical treatment that has to be done by a doctor with a prescription specifically for that patient and its use off-licence.
In addition to the above side effects and complications, many patients want to have only part of the hyaluronic acid dissolved and reversed by the Hyaluronidase enzyme and this can be very difficult to estimate. For instance, in the under eye area called the tear troughs for dark circles reversing the hyaluronic acid is very easy so a minute amount is used in a range of 75 units, note that a single vial contains 1500 units.However, depending on what material and cross-linking the hyaluronic acid has and how much has been injected more Hyaluronidase may well be required.
It also depends on where the injection has been and how compact the tissue is. For instance, sometimes reversing hyaluronic acid in the lips can be unpredictable because the tissue is very dense and the hyaluronic can be more resistant in that area.In the cheeks, if what I call a heavier hyaluronic acid is being used over a larger area (meaning a larger volume of initial HA), then again more enzyme is required with multiple small injections done and either a half or whole vial may well be required at one sitting.
How soon after Hyaluronidase injection for treatment of over-correction or misplaced hyaluronic acid filler can the patient have new HA filler re-injected?
What is the optimal timing?We know that within 30 minutes there is the majority of the HA filler reversed by the enzyme.We also know that the action of the enzyme can continue for 24 hours after the reversal with the Hyaluronidase injection, albeit at a very slow rate.However, the main reason for not re-injecting HA filler immediately is not that there may still be some Hyaluronidase enzyme present, but that the actual process of injecting the enzyme causes some swelling and possible bruising of the area. This means it will be very difficult to judge how much and where more hyaluronic acid (HA) should be injected.
In summary, the use of Hyaluronidase in the treatment of complications from the hyaluronic acid dermal filler such as over-correction or misplacement is not universally performed. It should only be performed by experienced practitioners who can assess the area and who have been given the adequate information as to the quantity and type of HA that was injected. They can then advise the patient accordingly whether they are suitable and then choose the correct amount of Hyaluronidase to inject.
Oculoplastic surgeons inject HA fillers and are often well qualified to use Hyaluronidase enzyme to reverse them either in their own patients or patients from elsewhere because they have a wide experience.
As an oculoplastic surgeon, I frequently am asked to reverse HA filler. This can be for reasons as diverse as not liking the appearance, because it has localised in an area and be apparent or asymmetry.Sometimes we have to reverse the HA if we are suspecting that there is an allergic reaction to the HA either early or late causing swelling and redness by removing the HA the trigger for allergy is reduced.