Case Study: Utilising Ultrasound

While working as an experienced medical aesthetic practitioner, dealing with complications from other injectors can be a regular occurrence. This is particularly true nowadays, which I believe is due to the prevalence of lay injectors providing treatment with little to no anatomical knowledge. It’s been my experience that these injectors generally regard dermal filler treatments as another beauty procedure until they go wrong and become medical procedures. As non-medics lack the knowledge and prescribing rights to cope with these situations, this leaves their patients without the appropriate care, leading to my complications clinic always being full.

This article will present one example of how I used ultrasound imaging – an invaluable tool in my clinic – to assist me when treating an aesthetic complication in a female patient.

Medical history

The patient, a 46-year-old woman, was referred to my complications clinic two months after receiving dermal filler injections in her forehead from a non-medic injector. The patient had originally sought aesthetic treatment because she felt long-term medical issues (which had no bearing on the complication itself or how I dealt with it) had left her looking tired and older than her age, and she wanted to feel fresher and more confident again.

I soon ascertained that the patient was aesthetic-naïve, meaning she had very limited knowledge of aesthetic procedures and had never had an injectable treatment before, so had trusted her prior injector without doing further research into the procedure in question. The original injector had advised the patient that she would benefit from forehead filler for facial rejuvenation, and the patient had agreed despite the injector not informing her of any of the risks involved.

Dermal filler of an unknown brand was administered with a needle across the central and lateral parts of the forehead, as could be seen through diffuse swelling in the area. The patient told me the original procedure was painful, and immediately afterwards she experienced debilitating headaches, followed by episodes of pain comparable to migraines. The severity of this pain forced the patient to become temporarily housebound and take time off work.

The patient contacted the original injector who administered hyaluronidase after initially being slow to assist. As the injector was a non-medic, I was unable to determine whether the hyaluronidase used had been obtained via a medical prescriber, or if it was a counterfeit product bought online. Following this, the injector told the patient that she could do nothing more for her, but the side effects persisted, so she went to see a medical practitioner in London who then referred her on to my complications clinic.

Anatomical considerations

The forehead is one of the riskier facial areas to inject because of the thin tissue and rich vascular network which has anastomoses to the ophthalmic circulatory system.¹ When considering forehead injections, there are techniques which focus on injecting both above and below the frontalis muscle. The forehead arteries are expected to run deep to the frontalis in the lower parts of the forehead and cross to its surface closer to the hairline.¹ The distribution of vessels is extremely variable, and as such, the precise location of vessels can only really be pinpointed by using ultrasound prior to and during forehead augmentation. Due to the limited tissue depth, it can also be difficult to discern whether the injections are above or below the frontalis without confirmation from ultrasound imaging.

There are multiple important vessels to consider when injecting the forehead.¹ Firstly, the supratrochlear artery travels cranially in the forehead. Adjacent to this is the supraorbital artery which, again, takes a similar course. Both are terminal branches of the ophthalmic artery. Slightly laterally at the side of the forehead, there are connections between the supraorbital and the superficial temporal arteries, which supply blood to the temple. All these arteries have potential connections to the eye through ophthalmic circulation and anastomoses, so the area contains a network of interlinked high-risk vessels.¹

Several complications could arise as a result of inaccurate injections in the forehead. Because there is so little space in the layers of the forehead, incorrect filler placement can cause compression of the vasculature, leading to venous blockage or vascular irritation. This can subsequently cause hypervascularity – a proliferation of blood vessels.² An occlusion can cause ischemia and necrosis of the skin, but in my experience, 90% of such cases are treatable if caught early (under two and a half days).

The biggest cause for concern is that occluding one of these arteries could easily send a filler embolus into the eye if care is not taken to avoid injecting into any vessels. Large emboli cause sudden, catastrophic blindness.³ However, it is theorised that smaller emboli may cause choke activation – a protective mechanism which shuts off certain areas of skin tissue detects noxious stimuli³ – but which, when affecting the eye, can lead to ischemia of the retina and irreversible vision disturbance in as little as 15 minutes.⁴

Addressing the complication

Patients who have experienced complications are often emotionally damaged, in addition to being in a great deal of pain. These patients frequently have self-blame, so reassurance that the situation is not their fault and that you will take care of them is central to their management. However, the initial consultation must also introduce the possibility that you may not be able to completely rectify the issue – patients’ expectations must not become inflated. Complications are often difficult, not only from a patient management but also a clinical perspective, and complete resolution is sometimes not achieved. 

When treating this patient, ultrasound imaging using a GE Venue Go ultrasound device with a 4-20 MHz linear probe allowed me to locate the filler deposit with its excellent resolution for imaging of superficial facial tissues. Figure 1 shows the ultrasound probe approximately 3cm above the brow, with the image depicting the patient’s right supraorbital artery highlighted in red; the black structure next to it is filler. The areas are visible as such because they are anechoic, meaning no sound waves from the ultrasound machine are reflected back. The lack of colour in the black deposit indicates that filler is in that area because the machine has not detected any blood flow within this fluid (gel) filled structure.

Figure 2 shows that the filler had also been placed close to the dorsal nasal artery, causing further risk as this is a branch of the ophthalmic artery. The filler had caused irritation and hypervascularity, both of which led to painful oedema. Because the filler was not injected intravascularly but was still compromising the vessel, I class this as a vascular adverse event rather than an occlusion.

Sometimes, flooding an area with hyaluronidase will rectify a filler-related complication if the product’s exact location is not known or ultrasound is unavailable.⁵ However, filler can become encapsulated, meaning a shell has formed around the product which hyaluronidase would not be able to breach without direct injection into it. The reasons for this can include patient immune or inflammatory responses owing to poor quality filler, placement or intra-procedural factors. The ultrasound imaging allowed me to inject directly into the filler capsules.

As can be seen in Figure 3, the needle can be accurately guided to the deposit. I injected a total of 300 units of hyaluronidase into the affected areas using a 1ml syringe and a 27 gauge, 1.75 inch needle.

This particular needle was appropriate for use alongside ultrasound because it can be seen clearly in the images but is still thin enough to be flexible and mitigate the risk of tissue trauma. I find cannulas for guided dissolution can lack efficacy due to their inability to penetrate the hyaluronic acid deposit.

I was able to treat this complication in one half-an-hour session. The patient experienced some bruising, but within a matter of hours she reported a significant improvement in her pain, and the headaches had subsided within three or four days. By the time I reviewed her two weeks post-procedure, she was no longer experiencing headaches at all.

The virtues of ultrasound

This case is an illustration of why ultrasound is crucial both when injecting into riskier areas and when addressing complications. Without ultrasound, I would not have been able to identify the exact location of the filler or which vessel it was obstructing. Using ultrasound is a skill I would recommend any medical aesthetic practitioner to hone, both for the sake of complication management and performing injectable treatments safely. To achieve a good level of proficiency, the best approach would be to use ultrasound most days for routine procedures. This consistency will help you become comfortable using the machine, familiar with vascular mapping and well-versed in adapting your technique to incorporate risk mitigation. This can be reassuring to patients because it demonstrates that you are prioritising their safety.

It is important to remember that not all ultrasound devices will provide the same results. Many practitioners use handheld machines which are exceptional for their size, but these will not supply as clear an image as a hospital-grade cart system like the one I use. However, especially when patients have significant complications and are upset, litigious or angry, I cannot take chances with image quality.

Acknowledging your limitations in this respect is crucial when considering which complication cases you choose to take on; there is no shame in saying that your technology or expertise is not advanced enough for more complex complications and referring the case. There may even be opportunities to shadow during such cases to see how they are managed, and indeed, I welcome referring practitioners to my practice for this. Ensuring you have sufficient insurance cover to treat complications is also crucial. We are all medical professionals, and we all need to continue to develop risk reduction skills; ultrasound is a brilliant tool to help us do this.