Cosmetic filler injections are most popular among the anti-aging procedures. The complications are likely to occur even under experienced hands. However, it is a duty of aesthetic physician to identify and manager these potential complications.
The increasing popularity of soft tissues augmentation procedures has led to a proportional increase in the number of complications. In this blog post we’ll try help the aesthetic practitioners to identify the complications as early as possible and manage them appropriately to improve the outcomes.
All dermal filler treatments can lead to one of following complications:
- Product-related: not certified (CE) products, permanent non-restorable products, antigenic nature of the material;
- Physician-related: Lack of knowledge, insufficient experience, not sterile augmentation/injection techniques;
- Host-related: Altered host defence mechanism.
It is important to be aware of all the above considerations to avoid of minimise the complications.
Product-related Complications
An injectable product can be:
- Non-permanent and biodegradable
- Semi-permanent and biodegradable
- Permanent and reviewable
- Permanent and non-reversible
Fillers are classified based on the histological reaction as volumators with little cellular response and stimulators with strong cellular reaction. A knowledge of this property of the filler substance may serve as a guide in predicting later inflammation or granuloma formation.
Physician-related Complications
Importance of Patients History
A history (anamneses) is important to avoid complications, as it helps to asses the physical and mental health, drug intake, history of surgery or previous fillers in the area to be treated, indications and contraindications of procedures in each individual case.
Knowledge of Anatomy and Topographic Anatomy
A thorough knowledge of the anatomy of the skin, other tissues (muscles, ligaments, nerves), function of these tissues, bones, sutures and vasculature in the treatment area is crucial for:
- For proper placement of filler material and the placement technique to avoid the lumps, bumps or Tyndall effect;
- To avoid inadvertent placement into vessel, which could lead to ischemia, necrosis, blindness and other similar vascular accidents.
Injecting in the correct plane is important for best results. It is important to know the differences in skin thickness in different parts of the face (see Figure 2). The thickness of the facial dermis varies between 0.4mm in lids and 1.2mm in forehead and cheeks. The outer diameter of 26G needle can be used as a rough gauge to guide the depth of injection as it measures 0.45mm, which is half the thickness of the dermis, or conversely the facial dermis is only about twice as thick as 26G needle. So, for a proper intra-dermal injection, the needle should be inserted at approximately 10° angle and one-needle diameter deeper. For injection into mid-dermis to treat moderate-to-deep folds, the needle should be inserted at an angle of 30°–40°, and for injection into deep dermis or supraperiosteal region to treat deeper folds, the needle should be directed at an angle of 45°–90°.
Vasculature and Ischemic Issues
Vascular compromise can occur because of inadvertent injections into certain vessels or as a result of external compression due to pressure from the injected material.
The high-risk areas leading to blindness are:
- Nose;
- Nasolabial folds;
- Forehead;
- Glabella.
The areas prone to necrosis are:
- Glabella;
- Nose tip;
- Lips.
Importance of Injection Technique
Dermal fillers may be injected using a needle or cannula based on the experience and comfort of the injector as both have their own advantages and disadvantages. In general, fillers should be injected slowly after aspiration, and the delivery of material should be in small volumes per pass and with least amount of pressure.
The use of small-caliber needles slows the speed of injection, and the use of blunt cannulas in high-risk regions, such as glabella, nose, and NLF, reduces the risk of injury to vessels.
Most important for a safe practice is a sterile workplace and strict asepsis during the technique to avoid infections.
In the next part of this blog, we’ll discuss early complications in more details and I’ll share some professional tips on how to avoid it. Stay tuned!