Does ultrasound provide the evidence to support aspirating with fillers?
To this day, some well-known aesthetic doctors do not recommend aspirating before injecting dermal fillers, they feel that there is a lack of evidence to support the practice, that it provides false reassurance, and that many positive reactions are false positives.
Dr Tim Pearce has recently purchased a portable ultrasound device – check out his blog looking at whether you should buy an ultrasound scanner for your aesthetic clinic – and it is clear to him that the insight he can get into living anatomy is going to change aesthetic clinical practice in the future, but will it end the debate surrounding aspiration once and for all?
In this blog, Dr Tim Pearce examines the arguments for and against aspirating when injecting dermal fillers, he reviews two cases of positive aspirates followed by ultrasound review, and discusses whether ultrasound provides the evidence to prove that aspirating should be best practice, especially in high-risk areas.
Dr Tim will be discussing more medical aesthetic training tips as part of his upcoming webinar series, so if you’re looking to increase your CPD-certified learning and want to learn more skills to make you a better clinician, then step one is to register for the free webinars by Dr Tim.
The rationale for and against aspirating before injecting dermal fillers
Dr Tim will admit that he is biased in this instance and is not an expert on the arguments against aspirating, because he has spent most of his career coming up for reasons in favour of aspirating when delivering dermal filler injections.
The reasons why NOT to aspirate
The core of this argument is that aspiration provides false reassurance; the reasons why you may get a negative aspirate when you are in a vessel are numerous, and just because you are in a vessel does not mean that you will get blood out when you aspirate. This is most observed when attempting to take blood. But in the case of dermal filler injections, there is also a thick product in the syringe that is blocking the lumen of the needle which means you cannot solely rely on aspirating to prevent a vascular occlusion.
The reasons why you SHOULD aspirate
Dr Tim notes that his ‘lightbulb’ moment when it comes to aspirating came when he stopped asking himself,
‘Am I in a vessel?’
and instead asked,
‘What is the probability that I am in a vessel?’.
This positions you, as a clinician, into performing a screening test, and in medicine we all understand that every screening test has a ratio of true positives, true negatives, false positives, and false negatives. Using screening for prostate cancer as an example, Dr Tim explains how prostate-specific antigen (PSA) tests have a false positive rate of approximately 70%, and a false negative rate of approximately 20%. If a man has a negative prostate test result, with symptoms, there is still a 20% chance that he has cancer, and if it is a positive test result, there is a 70% chance that he does not have cancer.
Of course, the public do not think in the same terms as medical practitioners, and Dr Tim believes that this may have crept into how the aesthetic community thinks about aspirating, which potentially clouds the views on both sides of the argument.
There will be firm opponents and firm supporters, but as almost universally true in life, Dr Tim believes that in between the two extremes lies the truth, and he is hopeful that ultrasound will shed more light on the debate. Let’s review a couple of case studies to understand further.
Case study 1: temple injection with positive aspiration
In this case example, Dr Tim’s wife, Miranda Pearce was having a dermal filler temple injection from his colleague, Dr Amy. This was being filmed for training purposes when a positive aspiration occurred.
Temples are an interesting injection site, according to Dr Tim, because they more clearly demonstrate the challenges that aesthetic clinicians face with depth and the aesthetic result achieved. If you inject superficially at the temple, you are at the level of the superficial temple artery, and in his experience severe volume loss treated superficially results in an unpleasant, spongey result which patients dislike. If you inject more deeply, at the level of the periosteum, you are limited with the ability to move around, and some favour the ‘gunshot’ technique proposed by Dr Arthur Swift. This is in theory the least likely place to find an artery and the most effective place to achieve the best aesthetic result – raising the tissue and hiding the shadow that defines temple volume loss. This deeper technique was used in Miranda’s case.
Months after the incident, and following the purchase of his new ultrasound device, Dr Tim had the opportunity to scan Miranda’s temple to locate the anomalous vessel, thus proving that aspirating was valuable in this case, as the vessel was clearly visible on ultrasound and not in the location expected.
Case study 2: chin injection with positive aspiration
During another training day, Dr Tim encountered a second case when injecting the chin. He explains that it is safer to inject the chin in the midline, on the periosteum, and also favours needle-on-bone for optimal aesthetic results because his experience shows that deeper injections are more stable over time when placed on the bone, compared to within the fatty layer above.
Whilst delivering the injection to the chin, aspiration was routinely performed, although there was no anticipation of encountering a vessel in this position or depth. This produced a positive result. The patient was then able to be retrospectively scanned using the ultrasound device, Dr Tim found the artery exactly where it should not be, near the periosteum in the midline, proving another case of anomalous anatomy identified by a positive aspiration.
In conclusion, both these cases highlight that the practice of aspirating prior to injecting dermal filler, especially in high-risk locations, does detect arteries that are also detected by ultrasound scans. In his opinion, this is clear evidence that a percentage of intravascular needle placements are detectable by routine aspiration. However, it is pertinent to remember that not all will be detected, and aspirating is not the only tool to mitigate this risk, especially when delivering large volume, bolus injections in one location.
Does aspirating work? Find out the answers in another recent blog from Dr Tim.
There is an emerging view that keeping the needle moving, when delivering these large bolus injections, might be safer than aspirating. Dr Tim is hoping to interview a pioneer on this topic very soon, so keep an eye on the Aesthetic Mastery Show playlist.
Dr Tim would love to hear your thoughts on aspirating, do the results from using ultrasound in the examples above make the case for aspirating a no brainer, or not? – let him know what you think by dropping a comment on social media, you can find Dr Tim Pearce on Instagram.
Aesthetics Mastery Show
ULTRASOUND: Should you buy one to be safe?
This blog follows our recent Aesthetics Mastery Show, in which Dr Tim Pearce discusses the pros and cons of making the investment for your aesthetics clinic.
Are you still anxious about delivering cosmetic injectables safely?
If you want to learn more about mastering medical aesthetic treatments and complications or conquering the anxiety of where to place your needle, then register for the next Dr Tim webinar.
Further complications resources
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.
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.