The Last Word: Questioning ‘Facts’ in Aesthetics

By Dr Tahera Bhojani-Lynch / 26 Mar 2020

Dr Tahera Bhojani-Lynch encourages practitioners to question ‘facts’ in aesthetics, with a particular focus on hyaluronidase

There was once a time in medicine when anything that defined our clinical practice had to be peer reviewed and was subject to medical trials before we took it on board as ‘best practice’. However, we all know that aesthetic medicine is a relatively new speciality and scientific papers can contain conflicting information, often recounting experiences and opinions rather than controlled or comparative clinical data. Many published papers are case records rather than clinical trials and studies are often cadaveric and in vitro, rather than in vivo, meaning interpretation is open to subjectivity and bias. So, where should we turn to in order to determine what is ‘best practice’ in our field?

I regularly find it very frustrating when practitioners stand up on stage at a big congress and state an opinion as if it is proven to be correct. It is then taken by the audience as the gospel truth, irrespective of whether there is any clinical data to support it, and then they it repeat as if it is an absolute fact that cannot be questioned or discussed– it becomes a given and can subsequently turn into ‘best practice’.

However, just because a claim is made by someone who is well-known and perhaps very reputable or knowledgeable, does that make it absolutely true? How often are their opinions unbiased, or without agenda and consequently the correct way to do things? Are we even allowed to challenge them without calling our own reputations into question, when so called ‘influencers’ and ‘key opinion leaders’ have the following of social media or the backing of rich pharmaceutical companies?

In this article, I present two statements or ‘facts’ about hyaluronidase that I have heard over the years on both national and international stages, that I believe can and should be questioned in order to help progress our ever-evolving specialty. I have chosen to focus on hyaluronidase because of its increased use associated with the rising number of aesthetic complications and poor aesthetic results over the years.

Just because someone states something, it doesn’t make it true, no matter how prominent, clever or important they are

‘Hyaluronidase has no longterm effects on the patient’s own collagen or hyaluronic acid production’

I regularly hear at conferences that if a patient has a poor aesthetic result following treatment with a hyaluronic acid (HA) dermal filler, then the practitioner can ‘just hyaluronidase it’. But should we be acting as if there are no potential repercussions of this treatment? First and foremost, hyaluronidase is not licensed for aesthetic use, or for the correction of poor aesthetic treatments or for use in an aesthetic emergency.2 There must be clinical need and good evidence to use hyaluronidase for any such off-license indications. It is also a prescription-only medicine, but is often used with casual regard to its actual mode of action and potential side effects.

Hyaluronidase is routinely used to correct poor treatments, granulomas, lumps and bumps, at the request of dissatisfied patients and in haste by worried practitioners. There are clinical publications discussing the effects of hyaluronidase as ‘dissolving’ hyaluronic acid,3,4,5 but there is little or no good evidence for damage to a patient’s own HA or collagen production following hyaluronidase use, and I am not aware of any that show clinical evidence that they do. In reality however, I believe that we do not actually know the long-term effects of hyaluronidase on the skin. Remember, just because there is no evidence published yet, it does not mean that there is no effect.

Of course, in emergency vascular events following HA dermal fillers, hyaluronidase use to improve vascular perfusion is well-accepted as the best approach for successful patient outcomes, even though there is little consensus for dose, dilution, efficacy and safety.2

However, anecdotally, myself and other practitioners have seen that when we have patients that have had repeated hyaluronidase use in skin, there are visible volume changes that do not recover with time, and textural changes, where the skin appears lax and thickened, with loss of subdermal support. I believe this is particularly evident in the periorbital area where there is naturally thinner skin and little or no subcutaneous fat.6

I had one patient referred to me who had received six doses of hyaluronidase in the periorbital area with two different practitioners, after both their original treating practitioner and the ‘expert second option’ thought the patient had persistent, protruding residual HA lumps following her treatment. When I assessed the patient, the tissue around one eye was completely de-structured – the skin was shiny, and the whole of the eyelid was affected – she looked awful. Upon examination, I discovered that the ‘lumps’ were not HA, but redundant skin that had thickened but felt like a hard pocket of residual HA. This had led her practitioners to repeatedly administer hyaluronidase with ever worsening aesthetic outcomes. It was evident from this case that not only is it important to have an accurate synopsis of previous interventions before any further remedy is initiated, but that also, quite possibly, repeated hyaluronidase injections may have an impact on the quality of the overlying and surrounding skin. I would urge practitioners to therefore think long and hard before they ‘just hyaluronidase it’ in non-emergency situations, and consider the possibility that hyaluronidase could potentially affect the patient’s skin. Ensure you take good before and after pictures and monitor the effects. When hyaluronidase is the only option for improved cosmetic effect, small volumes with low doses7,8 and allowing time for recovery of tissues between treatments might minimise disruption to the delicate balance of skin homeostasis.

‘Vascular occlusion with non-HA filler collagen stimulators cannot be treated with hyaluronidase’

When it comes to non-HA collagen stimulating fillers such as calcium hydroxylapatite (Radiesse), polycaprolactone (Ellansé), or poly-l-lactic acid (Sculptra), it is generally accepted that hyaluronidase is not an option for removal of the product, although I cannot find any clinical studies to reference this. Certainly, having contacted the manufacturers/distributors of these products, neither Sinclair nor Merz were able to give me any clinical data in favour for or against the use of hyaluronidase with these products, and so none advocated the use of hyaluronidase for emergency use or for poor cosmetic effect. There are even some verbal reports that treatment with hyaluronidase may actually make matters worse and cause unsightly nodules by reducing ‘volume’ in the surrounding skin. I have heard mixed reports from colleagues at conferences regarding this. I myself have experienced a venous occlusion following injection of a collagen-stimulating filler (polycaprolactone) which I successfully treated using hyaluronidase.

Many people believe that hyaluronidase breaks down or dissolves hyaluronic acid, but its established mode of action is to change and increase the vascular permeability.9,10 Because of this mode of action, it could be possible to treat collagen stimulators with hyaluronidase and it may help in serious medical emergencies like vascular occlusions. I therefore don’t agree that non-HA fillers, like collagen stimulators, cannot be treated with hyaluronidase; I believe that further studies in this area should be performed.


I am not saying we should never listen to experienced and renowned industry speakers as, most often, they do have fantastic tips and advice, which are supported by evidence. I simply want to try and persuade practitioners to consider themselves as scientists, as well as injectors, and look at the evidence rather than listen to and repeat the sound-bite. I encourage my peers to have the desire to question the facts they hear and relate it back to science.

Aesthetics is an emerging specialty and there is not enough unbiased data to substantiate much of what is proclaimed as ‘best practice’. I think when presenting to others, key opinion leaders should acknowledge when there is limited, or conflicting evidence for their claims, and highlight that their way is not the only way, and encourage their delegates to learn through questioning their presentation, rather than accepting it.

Practitioners must remember that just because someone states something, it doesn’t make it true, no matter how prominent, clever or important they are. If we keep regurgitating the same so-called ‘facts’ without questioning them, then we will never evolve – if we hadn’t stopped to question ‘established teaching’ we would all still be injecting directly into nasolabial folds!

Personally, I believe hyaluronidase can be used to treat venous occlusions caused by non-hyaluronic acid dermal filler collagen stimulators and I have treated two with excellent effect. I also believe that hyaluronidase affects the underlying structure of skin and can have long-term detrimental effects on normal dermal appearance. However, just because I say this, it doesn’t mean that it is true! I would invite my colleagues to share their knowledge with me, question my assertions and take the debate forward for the benefit of patients and practitioners alike.

Acknowledgements: Dr Bhojani-Lynch would like to thank nurse prescriber Helena Collier for her expertise and input in this article.

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