Does technology make cosmetic injecting safe?

Ultrasound-guided injecting is on the rise – but is it giving a false of sense of security?

Dermal filler injections are one of the most popular treatments in cosmetic medicine for enhancing and rejuvenating the appearance of the face. While widely considered a low-risk treatment many patients are still frightened of the risks of dermal filler. This can sometimes also translate to the practitioner being scared of treating patients. Of course, we all want great outcomes and happy patients.

In Australia, the most common dermal filler used to create lip enhancement and cheek contour improvement is made from hyaluronic acid. Delivered as a gel in a syringe of various rheological profiles, dermal filler is injected using a traditional needle or a blunt-ended cannula. When the gel is injected, there is a volumisation of the tissues to enhance and improve contours.

As we know, all procedures carry risk. There are common risks when it comes to cosmetic injecting, such as discomfort, swelling and bruising. These are not serious in nature and are not associated with poor outcomes.

Risks in cosmetic injecting

As mentioned, there are common risks that are acceptable, such as bruising and temporary swelling associated with injecting. Risks of more significance are vascular occlusion. This occurs when blood is no longer able to pass through a blood vessel, causing a blockage. This can cause skin damage and/ or necrosis if the vascular occlusion is not treated. A blockage may also occur distant to the site of injection, resulting in blindness. This is where a blockage travels up the chain into the ophthalmic blood vessels.

These are risks that we need to inform our patients of to gain full consent. We should include the statistics when we are having our consultation. The reported risk of a vascular incident when injecting filler using a needle is 1:6410. Comparing the risk of the same filler being injected with a cannula, the risk is much lower, being close to 1:40187. This means that using a cannula reduces the risk significantly.

When we discuss blindness, the accepted risk to quote our patients is that blindness may occur in one in very 100,000 injections. It has occurred twice in Australia and is devasting to the patient, but also to the practitioner.

So, the question is, can we reduce the risk with technology, such as ultrasound? The simple answer is that we cannot quote reduced risk figures to our patients when we use ultrasound and dermal filler so, statistically speaking, using ultrasound is not safer.

Ultrasound devices for cosmetic injectables

The risk of dermal filler complications can frighten people away from having otherwise be a life-changing treatment. While nothing will ever compare to the safety of having dermal filler by a clinician with extensive training and experience, a newer technique known as ultra-sound guided dermal filler injections has gained significant attention in recent times. But just because it is newer does not necessarily make it better. I know that this is an area of much discussion, but it is important to note that the use of ultrasound for any cosmetic injections is not standard procedure, nor have any rules changed around the use of this equipment.

So, let’s break down ultrasound and the use in cosmetic injecting. How can it be beneficial and are all devices the same?

Ultrasound technology has been around for decades, and has changed the practice of medicine. It is a simple, non-invasive way to visualise the skin and identify anatomical structures, and diagnose certain diseases and medical conditions.

Ultrasound uses high-frequency sound waves to produce images. It works by emitting sound waves that bounce off internal structures of the body and return to a device called a transducer. The transducer coverts the reflected sound waves into images that are displayed on a monitor.

In the context of dermal fillers, ultrasound can be used to map out planned treatment areas and identify key structures that must be avoided during the treatment. It can also be used to track the progress of your treatment in real time, assess the location of previously injected dermal fillers, and to identify and treat dermal filler complications.

Advocates of ultrasound-guided dermal filler injections claim that it reduces the risk of complications, enhancing patient safety. However, currently, there are no peer- reviewed longitudinal studies demonstrating that ultrasound- guided dermal filler injections improve outcomes and reduce risk.

While theoretically they might, theory doesn’t always translate into practice. Just because a clinic offers ultrasound-guided injections of dermal filler does not mean that the treatment will have no risk, and does not guarantee a result. Skilled sonographers who specialise in performing ultrasound scans spend years learning how to perform them correctly and accurately.

Ultrasound-guided injections: key considerations

It is very important to remember, like all things with technology, you get what you pay for. Cheaper devices run around $6-7K. Having one may make you feel like you are reducing risk, but what you see with a cheaper device is poor clarity and definition and this can give you a false sense of security as you see no vessels – and potentially might progress with treatment thinking that you are safe.

A skilled sonographer uses an ultrasound device that runs around $80K+, which is often for the general injector, but gives the best detail. The more expensive machines are also large in size, and give accurate, highly detailed images. If you have a cheaper handheld device, you may simply not be able to see what you need to see. Furthermore, incorrect use of ultrasound may significantly increase the risk of your cosmetic treatment by giving clinicians a false sense of security, meaning they may be more likely to inject in risky ways, and inject areas that are beyond their scope of practice and training.

For example, you may perform ultrasound on the nasolabial fold and see no blood flow through the area. We know that anatomically this area carries the facial artery and is high risk. There are other considerations, too:

• What does the absence of the expected key elements in the images tell us?
• If the ultrasound shows no blood flow, does this mean that you are safe to inject?
• Does it mean that the ultrasound could not see the blood flow and you will now proceed to inject in an area that you might not have before? Does this actually increase your risk, since you assume you are now safe?
• What if your ultrasound is not correctly calibrated?
• What if you press too hard on the ultrasound probe and occlude the vessels?

Perhaps some of these questions begin to highlight that when we add technology into our clinical practice, we need to consider where there might be gaps in the technology, our skillset or our ability to objectively look at the data and potential errors that creep in. Look at the images on the next page. They were taken of the same tissue with different ultrasound devices. The first image is most defined and the most expensive equipment. The second is mid-range and the final image are using a cheaper hand-held machine.

Some things to seriously consider when clinics advocate their treatments because they are done under ultrasound guidance include:

• What experience do the practitioners at the clinic have? The use of ultrasound is unlikely to replace training and experience in reducing risk through safe injection techniques.
• How much experience do they have with ultrasound? Most practitioners will have just bought the device and done a weekend course. This means that the ultrasound is unlikely to be performed correctly, increasing risk through a false sense of security.
• Will the use of ultrasound make the injector take unnecessary risks because ultrasound is giving them confidence they otherwise would not have?
• Does ultrasound actually result in better patient outcomes (either with a better result or risk reduction)?
• Does the use of ultrasound increase the severity of complications because injectors think they are in the clear when they in fact are not?
• Ultrasound was not designed to be used for dermal filler detection.

Nothing is ever likely to replace safe and experienced techniques when reducing the risk of dermal of dermal filler injections. The same debate has occurred countless times with previous techniques and tools, eg, the use of a cannula vs sharp needle, to aspirate or not aspirate. Both the use of a cannula and aspirating before injecting were claimed to be safer techniques, and while they may reduce the likelihood of a complication, some of the worst complications have occurred when dermal filler has been injected because the practitioner forgot anatomy, thinking they were ‘safe’.

Ultrasound is no different, and from previous experience, over-confidence that comes with these practices that emphasise ‘safety’ often expose patients to a much higher risk than they would be if practitioners simply remained cautious and conservative, and stuck to safe techniques.

Look at the image below of HA fillers. It is very difficult to visualise for the non-trained practitioner, or even the practitioner with experience.

Ultrasound may have utility in improving dermal filler safely but mainly with the treatment of complications by allowing precise dissolving by dermal tissue that has caused the issue. At this time, there is no data to prove that the use of ultrasound reduces risk as there are far too many variables, and no studies available.

At this time, we will watch this space with interest, and see what emerging science comes forward. Reducing risk is always of benefit to our patients and always something we should take into account. AMP