January 25, 2024

Aesthetics Mastery Show Dangers of Non-Reversible Fillers

There is one pathology in medical aesthetics feared above all others – necrosis.

In this blog, Dr Tim Pearce explains more about necrosis, and what you can do to reduce the likelihood of this ever happening to one of your patients. He also discusses vascular occlusion and non-reversible dermal fillers as he explores how to reduce the risks of causing necrosis.

To be among the first to receive exclusive updates on the launch of Dr Tim’s new movement, featuring an immersive 3D learning experience, comprehensive Botox lessons, and much more, simply sign up here to join the priority waiting list.

What is necrosis?

When we think of necrosis, we usually think about blackened areas of skin where the tissue has already died. But what makes tissue die?

When you reduce blood flow to a particular area, it seems intuitive to think that tissue will fail to thrive and slowly die through the simple lack of oxygen. However, it is much more serious than a deterioration in normal function. When you have a necrotic wound, the cells undergo a much more violent and destructive process.

The destruction of the cell does happen due to a lack of oxygen; as oxygen reduces, it means we no longer have the single unit of energy used to power the cell, sometimes referred to as ATP (adenosine triphosphate). The loss of ATP means the cell can no longer regulate itself; losing the ability to control its power causes the cell to destroy itself. It can no longer control its membrane gradients, causing an influx of sodium and an increase in water within the cell, causing it to swell. The rough endoplasmic reticulum also swells due to an inability to control ion balances and this can trigger an influx of calcium.

All these processes cause mechanical stress; however, the most violent thing to happen is the activation of the cell’s digestive enzymes. Cells are always breaking down molecules, but in a controlled way, and in controlled compartments; as soon as there is an influx of calcium, it starts to activate many of the cell’s destructive enzymes, and it starts to digest itself by autolysis. This results in leakage of the cell’s contents, including the destructive enzymes, into the cell tissue, destroying neighbouring cells. This is the necrotic pathology.

Is it common to see necrosis in aesthetic practice?

necrosis diagramWhen asked how many cases of necrosis he has seen in his career, Dr Tim’s answer is zero. This is because, although he has experienced a vascular occlusion event, it was diagnosed and treated swiftly to prevent anything bad from happening. Within his clinic, multiple aesthetic clinicians are practising daily and during the 15 years of running SkinViva Clinic, there have been 27 vascular occlusion events. However, all were diagnosed and treated rapidly and appropriately, hence zero patients went on to have a necrotic wound.

It makes sense that aesthetic clinicians should be trying to avoid necrotic wounds, rather than simply focusing on the avoidance of vascular occlusion, which would be a narrow strategy. It is paramount to understand that you need a different system to prevent necrosis than you do to prevent vascular occlusion, warns Dr Tim.

How to prevent necrosis in aesthetic practice?

To understand how to prevent necrosis, we must comprehend the stages that you might see develop, and the amount of time you have got to solve each of these problems; the key being not to panic. Learn the 5 early warning signs of a vascular occlusion when injecting fillers.

How long have you got from blocking a vessel before necrosis starts to set in? Medical knowledge highlights that tissue can survive for several hours with no blood supply. For example, in the case of severed limbs, where reattachment has happened up to eight hours after the limb has been completely dissected from the body. This gives some reassuring clues. Similarly, another example is pressure sores. These are well-studied in medicine, although pressure necrosis is slightly different. If you reduce oxygen supply to next to zero by creating pressure over tissue, the earliest sign of a pressure sore developing is around two hours.

In aesthetic medicine, there are anecdotal cases where a practitioner has injected filler, they or someone else has diagnosed a vascular occlusion, and then observed tissue breakdown. Usually, over time you will see small pustules forming within 24 hours of a venous blockage. Even at this stage, there are many case reports where clinicians restored blood flow and there was no necrosis. This evidence leads Dr Tim to believe that we have quite a long time to get this right, but it is hours and not days.

If you diagnose a problem immediately, while still in the clinic, you are in the best possible position to do something about it, and quickly. Although, that assumes that you have injected a dermal filler product that can be dissolved with hyaluronidase. Read up on the dangers of using non-reversible dermal filler products.

Injection techniques can help to reduce the risk; however, there is no such thing as an unsafe technique or a safe technique, there are just shades of grey between those two spectrums, explains Dr Tim. Many steps make a system safer; it is never simply one individual thing that reduces risk.

One safety step you could add to your system is aspirating. This test has been proven to detect intravascular placement a high proportion of the time, approximately 30-50%, depending on the published paper, and there are many things you can do to increase the sensitivity of the test to around 80%. You will not reduce your risk to zero though, because you will require additional steps. Dr Tim notes that it is very important to collect and learn as many different safety steps as possible, over your career, using them like an airline pilot’s checklist, and never relying on a one-step approach.

He offers another note of caution with cannula use. Many aesthetic practitioners believe that using a cannula to inject is a perfect way to be safe. Cannulas have a lower probability of vascular exclusion than a needle, making them approximately four to five times safer, which is fantastic. Unfortunately, the downside with cannulas is that when you are in a vessel, you tend to stay in the vessel. Granted, it is much harder to get into one, but if you are unlucky and then you are happily injecting product, the likelihood is that you will deliver more into one place, and inside the vessel. The nature of a cannula, with only one entry point, depending on where you are injecting, means that you spend more time in one place and the potential size of a vascular occlusion will be greater. The risk of vascular occlusion frequency is reduced when using cannulas, but the severity risk is much increased. This situation can be compounded with catastrophic results if cannula use is combined with a non-reversible dermal filler product.

Check out these other great blogs from Dr Tim:

Dr Tim loves to receive questions, comments, and data on clinical practice experiences from his followers. You can find Dr Tim Pearce on Instagram.

Aesthetics Mastery Show

PERMANENT brow ptosis from a cannula?! Temple filler safety tips & cannula advice

Dr Tim says:

“In this episode I address the feared pathology of necrosis in medical aesthetics and what you can do to reduce the likeliness of this ever happening to one of your patients. Emphasising the need to differentiate between necrosis and vascular occlusion, I also highlight the importance of a comprehensive approach to minimise risks. I also share a real case example involving a severe injury from a non reversible filler so that we can all learn the importance of product selection and reducing risk for patients. Thanks to Krysta for sharing her story.”

Watch the full Aesthetics Mastery Show here.

Follow Krysta’s journey on TikTok here: https://www.tiktok.com/@disfiguredbeauty

Commenting on the YouTube video,

@tracymullane8818 said:

“Excellent explanation of cell death and the difference between vascular occlusion and necrosis! Very interesting, thank you.”

@weronikaaugustyn623 asked:

“Could you please clarify if these cases of vascular occlusion happened while using concentrated calcium hydroxyapetite filler or was is diluted or hyper diluted? I was told that the risk of serious VO using diluted CaHA is much lower.”

See replies to this query along with more feedback and comments from practitioners and clients on our YouTube channel.

You can also subscribe to our YouTube channel for really useful regular tips and advice.  YouTube

3D Anatomy Learning Experience

3D learning experience movement

In the next few weeks, Dr Tim Pearce is going to be launching something amazing that involves an incredible 3D learning experience for injectors, a community of clinicians on the same mission as you to help you achieve your goals, and exclusive online access to him and his team. Be the first to join the movement by joining the priority waiting list.

Dermal Filler eLearning Courses

If you want to increase your knowledge about safe and effective dermal filler injectable treatments, Dr Tim Pearce offers a series of fabulous courses. The foundation level is a popular starting point, with many delegates continuing to complications courses focused around safety, including how to minimise the risk and how to handle things if the worst occurs:

Both give CPD and certificates on completion and are highly rated by our delegates.

In addition, browse our FREE downloadable resources.


Dr Tim Pearce eLearning

Dr Tim Pearce MBChB BSc (Hons) MRCGP founded his eLearning concept in 2016 in order to provide readily accessible BOTOX® and dermal filler online courses for fellow Medical Aesthetics practitioners. His objective was to raise standards within the industry – a principle which remains just as relevant today.

Our exclusive video-led courses are designed to build confidence, knowledge and technique at every stage, working from foundation level to advanced treatments and management of complications.

Thousands of delegates have benefited from the courses and we’re highly rated on Trustpilot. For more information or to discuss which course is right for you, please get in touch with our friendly team.

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