Dr Tayyab Bhatti details how he successfully treated a patient for a tear trough deformity using hyaluronic acid dermal filler
‘Catching someone’s eye’ is often the first form of non-verbal communication, but it can also tell you a lot about a person. It acts as an indicator of their chronological age, general wellbeing and physical attractiveness. Dark circles and deep lines around the eyes are not deemed as an attractive feature. A prominent tear trough (TT) deformity is the sunken appearance of the lower eyelid region which casts a shadow that is resistant to cosmetic concealment.1 This can make an individual appear tired, despite adequate resting, and can make them look aged beyond their years. The causes of TT deformity include ethnicity, volume loss with age, laxity and changes in skin thickness, hyperpigmentation and the prominent pooling of venous superficial vessels contributing to the illusion of depth. An attractive lower lid region should display a relatively smooth transition between the preseptal and orbital portions of the orbicularis oculi (OO) muscle and continue into the upper malar region without a definable transition point.2
The most recent classification is by Hirmand,3 which grades the deformity from I to III: mild, moderate or severe (Figure 1). It is important to highlight the severity of the deformity to patients using picture examples and explain the possible expectations of outcome with treatment at this stage. Although a Grade 3 severe TT can be improved, it is unlikely to be fully restored to how it appeared when the patient was younger without the need for multiple treatments or surgery.
There are multiple treatment options available in aesthetic clinics for TTs, including topical cosmeceuticals, platelet rich plasma (PRP), microneedling and hyaluronic acid (HA) dermal fillers.
In my practice, I solely use Teosyal Redensity II (RD2) for all TT treatments. It is the first filler specifically developed to provide a solution for the tear trough and, if injected correctly, is less likely to migrate and form lumps like some other fillers.4 RD2 contains a mixture of cross-linked and non-cross-linked HA chains, giving unique viscoelastic properties, allowing it to integrate into the tissues evenly.5 I only ever use a maximum of 1ml at any one sitting for both eyes. I find that RD2 does not cause a huge amount of swelling, which is great when treating this delicate area.
In younger patients with good skin tone and little laxity, I prefer to use serial point injecting (multiple, evenly spaced small boluses of HA using a 30G needle). For older patients, over the age of 50, to reduce the risk of bruising, I like to use a 27G or 25G cannula; 38mm is long enough for most treatments. The risk of intravascular injury is rare in this area as long as you avoid the terminal branch of the facial artery called the angular artery.6 This runs alongside the nose towards the inner canthus supplying blood to the upper and lower eyelids as well as the nose; an appreciation of the anatomy here is essential. Be aware that anatomical variations of vessels can occur.7 Although the incidence of ocular blindness is a very rare occurrence following TT injections, patients must be warned about this risk.8
A 28-year-old female patient visited my clinic complaining of a dark line under the eyes that she felt was making her look tired; this was her first TT treatment. Once she was counselled and consented, the area around the TT region was cleaned with Clinisept+.
I like to have my patients sitting at a 45-degree angle, as lying flat can obliterate the deformity and hence make targeted injections difficult. I ask patients to keep their eyes open whilst looking upwards. This stops them from squeezing their eyes tighter if their eyes were closed, which in turn leads to them raising their cheeks during injecting, which can obscure the TT.
I always inject the deeper TT deformity first. The needle was inserted perpendicular to the skin at the most lateral part of the TT. The bevel of the needle should be pointed away from the eye. Aspiration remains controversial; however, some practitioners may prefer to do this. As this is a delicate area to inject I avoid unnecessary movement and inject slowly. Approximately 0.05-0.1ml of HA was deposited above the bone, but below the OO muscle. There is the temptation to inject superficial to the OO muscle, which does give the immediate gratification of observable filling; however, be warned this can lead to filler migration as the orbicularis muscle squeezes and can push the filler medially. The needle was removed and gentle pressure was applied immediately.
At this stage, it is tempting for the injector to see if there is any bleeding but removing pressure too quickly may cause unwanted bruising. After gentle pressure was applied, the next point of injection was more medial and was placed in a similar manner, and I continued moving more medially.
This serial point method is excellent to treat mild to moderate deformities. I stopped injecting the first side before I had used more than 0.5ml. Gentle massaging along the TT helps the product to integrate smoothly. This is a good opportunity to show patients the difference between the treated and untreated side whilst they are sat up. I then continued the same method on the other side; stopping to ask about any symptoms such as pain or visual problems. Practitioners should stop injecting immediately if there are any concerns.
I used a total of 1ml of product in total. If I was to have used a cannula, I would make my entry point with the anchor needle just lateral and below to where the TT ends. I would need to make sure there was sufficient length for the cannula to get close to the canthus region.
Once the cannula is inserted, before starting to inject, I try to tent the cannula to determine its depth. If you can clearly see the cannula shaft tenting the skin, the depth is too superficial and you are above the OO muscle. Withdraw and advance again with a deeper angle. If you are below the OO, you will see no tenting. Whilst slowly withdrawing the cannula, I would deposit small beads of filler in the TT line with small gaps between each bleb. This allows for expansion of the filler during hydration and reduces the risk of overfilling. Once treatment was finished, I gave general post-dermal filler advice such as the avoidance of sun beds/saunas, avoiding alcohol for the rest for the day, and trying to stay upright for the next four hours, but strongly emphasised the need to avoid strenuous activity for 48-72 hours, as a small vessel can start to bleed and cause bruising if not noticed. Swelling post procedure was minimal; however, if noticed, I advocate using antihistamines to reduce the duration and severity of symptoms.
After four weeks, the patient returned for a follow up. She had not suffered any significant swelling or bruising. The dark lines had improved and a more vibrant and youthful look was achieved. The patient had noticed the skin around her eyes had become lighter; she was very happy with the results. At this stage, further filler could be injected, however, it was not needed in this case. HA lasts between six and nine months in this area, however, if its injected deep to the orbicularis muscle I find HA breakdown is slower and lasts closer to 12-15 months. As this is an advanced technique, it is advised for injectors wishing to use RD2 to attend organised workshops by the product manufacturer to become competent in this technique and have an in-depth knowledge of the anatomy and managing complications should they arise.