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January 27, 2026
Dr Tim Pearce
Many aesthetic clinicians lose heart when it comes to injecting dermal fillers due to the spectre of vascular occlusions looming large, leading to fear and a lack of confidence, but fear not, Dr Tim Pearce is here to show you how to inject more safely and avoid this definitely-avoidable-situation. For more tips, have a read of the first blog on dermal filler safety: vascular occlusion and necrosis prevention.
In this blog, the second of two, Dr Tim will give you the insight that you need to stop being constantly afraid of causing vascular occlusions, allowing you to move forward and build your practice, giving you the skills to avoid and control the chances of this complication. He has hand-picked some of the common questions he receives on the topic.
Do you feel anxious about causing complications? Many clinicians feel so overwhelmed with the thought of causing a vascular occlusion that it stops them growing their aesthetics business. Dr Tim is currently hosting a webinar series to help you overcome your fear of complications so that you can uplevel your knowledge, and increase your CPD-certified learning to build a successful aesthetics business. Sign up here >>
Which techniques should you avoid in high-risk areas?
The factors that make an injection high risk are the location and the volume of filler injected. If you are injecting in the upper face and using large volumes in short periods of time, this is the most likely way you could cause a very bad vascular occlusion, involving vision loss or stroke. Therefore, it is imperative that as practitioners we think about reducing the volume injected in each high-risk area, and about ways that decrease the frequency of the risk of a vascular occlusion.
Think about the relationship between frequency of risk and severity of risk; Dr Tim would choose avoiding severity and increasing frequency if he were injecting in a high-risk area. In practice, this means small amounts of product delivered with lots of checks in between.
An illustrative example of a high-risk injection is the so-called five-minute-nose-job procedure. This involves large volumes of filler delivered in a short period of time. To reduce risk, if we make it a fifty-five-minute-nose-job and ensure we are validating safety and normal capillary refill is verified between each injection, the risk is much reduced.
What makes the glabellar region more high risk?
The high-risk nature of the glabellar area is due to the blood supply to the face which comes from two arteries – the internal carotid supply and the external carotid supply. The internal carotid supplies the brain and the eyes and branches off as the ophthalmic artery to supply the supratrochlear, supraorbital, and lacrimal arteries. Thus, anywhere in the upper face is much closer to this important blood supply.
If you inject a large enough bolus of filler into the glabella, where most of these arteries are at their largest and most central, you have the highest chance of causing a complication like stroke or blindness due to the proximity to those large vessels that supply the brain, making it a high-risk area for injection.
Dr Tim believes that there is another factor that makes the glabella a high-risk area and this is down to the connective tissue which makes compression necrosis more likely. If you read the package insert for most dermal filler products, it will state that the product is contraindicated in the glabella. This is partly down to the risk posed by the arteries, as discussed, but Dr Tim also notes that there is a different kind of necrotic injury caused by compression of the capillaries. This causes a linear necrosis directly underneath the crease, if you inject a frown line with a thick product, for example. You will see a line of necrotic injury that is caused by compression of the capillaries, it does not follow the shape of an artery, nor the shape of the filler. He has seen a couple of cases in his career and believes that this represents an additional risk with injections in the glabellar region.
What are your thoughts on using non-reversible dermal fillers?
When thinking about risk with patients, Dr Tim explains that we need to justify any additional risk. If you plan to use a product that is high risk – and anything that is not dissolvable is high risk – you should have a clear indication as to why that is the better product for your patient.
Typically, this might be due to an intolerance to hyaluronic acid (HA), noted perhaps with a prior delayed onset nodule reaction that has happened more than once with the same product. Einstein noted that if you do the same thing and expect different results, that is the definition of insanity. Thus, in medical aesthetics, it is good practice to always change a variable if a patient has a problem, to reduce the risk of the same thing happening again.
In such a case, Dr Tim may choose a filler product like Radiesse® (calcium hydroxyapatite) instead of HA. Of course, the problem may not necessarily be a reaction to an HA product, it could be an inability to achieve the desired aesthetic result. There are indications for non-reversible dermal filler, but Dr Tim agrees that it puts more pressure on the practitioner to ensure that this is in the patient’s best interest and cannot be achieved with a safer product that could be dissolved if required.
What do you do if you have a vascular occlusion with a non-reversible dermal filler product?
Many of the manufacturers of non-reversible dermal fillers recommend certain protocols in the event of a complication, and that may include the use of hyaluronidase, and other injected solutions. However, the problem is that there is next to no evidence that you can dissolve such products effectively enough to prevent a necrotic injury in the event of a vascular occlusion.
In such a situation, there is likely to be a blood vessel that is blocked to some degree, and the aim is to improve it as much as possible, through injection of other excipients, massaging to encourage opening of the blood flow, taking sildenafil (Viagra®), or the use of a hyperbaric oxygen chamber. All these efforts might decrease the size of the injury or even contribute to there being no injury, but it is much less certain than having a dissolving agent (like hyaluronidase) that will break down an HA product into tiny monomers of sugar.
You should be prepared for such a protocol if you are going to use a non-reversible product, and the shortcomings that it brings including the reduced likelihood of preventing necrosis if there is a problem with vascular occlusion.
Check out this blog from Dr Tim on the dangers of using non-reversible dermal filler products including a case study of necrosis with Radiesse®.
Can you inject patients in an area with a scar?
A viewer noticed in one of Dr Tim’s educational videos that he was injecting a patient who had a scar on her lip. The practitioner had been taught not to inject patients if they have a scar in an injection site area because there is an increase in risk and wondered what Dr Tim’s justification process is for treating a patient with a scar.
Dr Tim approaches risk differently, unlike those who think that everything is black or white. He believes that risk is relative and there are always exceptions to any ‘oh that never happens’ arguments. A patient may appear to be a higher risk, but that does not mean that you should choose never to treat them without doing a full assessment first. You may find as you make your decision that the risk is slightly higher than a standard patient, but not so high as to not justify the difference you can make for them by treating.
When considering injecting a scar around a lip, if it is a simple scar, there is little increased risk than in other areas if you assess the individual anatomy. You can test the depth of your needle in the lip, by elevation, to ensure you are not within the labial arteries. Similarly perform small volume additions at a time so you can assess in between injections, you may choose to aspirate more often for reassurance, and if you have access to a device, you could use ultrasound before the treatment to determine if the scar has influenced the anatomy or would impede your technique in any way. This level of evaluation might enable you to step into an area that might be seen as a high risk, but to do it in such a way that makes it a justifiable risk, says Dr Tim.
Is surgical rhinoplasty a contraindication to doing non-surgical rhinoplasty due to the risk of vascular occlusion?
With surgical rhinoplasty, the problem is that the more often the nose has been operated upon, the more scar tissue is present, and the anatomy might be changed. Sometimes, the columella artery is tied off during a surgical rhinoplasty, for example, leading to less blood in the area. There may also be adhesions, meaning that there is very little room for a filler gel to expand and to reshape the nose, without compressing capillaries.
Dr Tim explains that this is a big risk factor. If you have an area that is full of scar tissue and you inject a large volume of filler, it is likely that it will compress the vessels in that area, perhaps not the larger ones to a greater extent, but certainly the capillaries which are much easier to compress.
His suggestion, and this can equally be applied to those patients who have not had rhinoplasty surgery is to assess the amount of room in the nose before you start to perform the non-surgical rhinoplasty injections. Do this by palpating the nose, feeling for a potential space for the product; a good indicator would be a relatively soft nose that is easy to move, rather than one where the skin feels tightly adhered or with little movement. You can then be more cautious as you add volume, knowing the space you have, assessing in between each injection and making sure the blood flow is normal. This will allow you to avoid chasing an aesthetic result at the expense of the amount of pressure that you might be creating as you inject.
If you have any further questions or comments about vascular occlusions and necrosis, you can find Dr Tim Pearce on Instagram.
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Aesthetics Mastery Show
Vascular Occlusion & Necrosis Prevention | Dermal Filler Safety Advice for Injectors
In this episode, Dr Tim talks about the nightmare scenario where a vascular occlusion is heading towards necrosis. He shares his tried and tested advice for preventing a dreaded VO. Watch the full Aesthetics Mastery Show here.
Read more and join in the debate on our YouTube channel.
Filler Complications eLearning Courses
If you want to increase your confidence by learning how to handle complications, Dr Tim Pearce offers two comprehensive courses that are highly rated by our delegates:
Both give CPD and certificates on completion.
In addition, browse our FREE downloadable resources on complications.
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.
