Direct versus indirect correction is a key principle in filler treatments and applies to nearly all facial areas. Direct correction is when an area is treated by injecting filler specifically into that area (i.e. filling a tear trough or hollow in the case of under-eyes). Indirect correction is an important filler technique where one area of the face can be improved indirectly by treating a neighbouring or even more distant region of the face. In the case of tear troughs and under-eye hollows, this may involve first treating the mid-cheek area to provide foundation and support for the under-eye soft tissue. More distant indirect correction may involve treating both the temples and outer cheeks, both of which can improve tear troughs and hollows by tightening the orbicularis oculi muscle that circles the eye, which in turn can stretch the overlying skin and reduce muscle resting hypertonicity, which improves the appearance of the hollows. This process is called myomodulation, which essentially describes the technique where fillers can be used to either enhance or inhibit muscle action depending on how and where the filler is injected. To read more about indirect versus direct correction and myomodulation, please refer to the Advanced Information Section of the Full Face treatments.

Careful facial assessment is crucial in all filler treatments and in particular, the eye region. This includes an assessment of the facial skeleton, which provides structure and support for the overlying soft tissue. Consequently, patients with a deficiency in cheek projection (maxillary hypoplasia with a negative vector), whether genetic or through ageing, are more likely to develop tear troughs as they lack bony support. It is important, therefore, that in those patients, structural support is created by injected a higher density filler deep onto the bone, providing better projection of the mid-face and an improved platform for the overlying soft tissue.

The canthal tilt is also an important part of the assessment in periorbital aesthetics. The canthal axis is an imaginary line between the outer corner (lateral canthus) and inner corner (medial canthus) of the eye. The canthal tilt is the angle this axis makes with a horizontal line. It essentially describes the degree to which the eyes appear to slant in an individual. A neutral canthal tilt means that both corners of the eyes are at the same level and there is no slant. A positive canthal tilt is where the outer corner of the eyes are at a higher position than the inner corner, such that the eyes appear to slant upwards. Females ideally have a degree of positive tilt of between 5-10 degrees as this is perceived as being more feminine. Too much tilt, however, can make the eyes look ‘cat-like. Men ideally have a neutral to small degree of tilt as this is perceived as being more masculine and attractive. Consequently, an exaggerated positive tilt in a male can feminise the eyes. A neutral tilt in a female or negative tilt (where the eyes slant downwards laterally) in both females and males is associated with facial ageing. As part of peri-orbital or eye-area enhancement, cosmetic fillers can be injected using advanced techniques to subtlety modify the ‘apparent’ canthal tilt in selective individuals to optimise the appearance of the eye area further. These techniques involve very careful and intricate micro-injections onto the bone of the outer orbital ridge (lateral canthal region), in combination with using an indirect myomodulatory action to rebalance the eye muscle and modify the pull on the eyelids and outer eye corner. These techniques should only be done by specialists with extensive experience of treating the eye-area. More profound changes, however, require surgical intervention. 

A tear trough is a groove or furrow located at the junction between the lower eyelid and the upper cheek, beginning at the inner corner of the eye (medial canthus), ending at an approximate point below the pupil (corresponding roughly to the mid-pupillary line).  Anatomically, it corresponds to the boundary between the inner (palpebral) and outer (orbital) portion of the circular sphincter muscle of the eye (orbicularis oculi). They can develop from a young age due to a genetic predisposition, where they tend to be relatively mild. They are, however, also a common feature of the ageing face. In some individuals, particularly with advancing age, the tear trough can become continuous with another indentation called the palpebromalar groove that starts from the outer corner of the eye (lateral canthus) and also runs downwards along the lid-cheek junction meeting the tear trough towards the middle. Although the two grooves appear to be continuous, studies suggest that they may have somewhat different underlying anatomical structures. There is also an important distinction between the tear trough and a third more diffuse and less defined indentation called the nasojugal groove, which like the tear trough starts at the inner corner of the eye but continues more obliquely downwards (corresponding to the space between the lower border of orbicularis oculi muscle and the levator labii superioris alaeque nasi muscle). The nasojugal groove can also appear to communicate with, yet another, fourth indentation called the mediojugal (mid-cheek) groove that, as its name suggests, runs obliquely downwards and outwards across the middle of the cheek. The nasojugal groove is often mistakenly referred to as the tear trough, and in some individuals differentiating between a nasojugal groove and true tear trough can be difficult especially as they run very close to each other towards the inner corner of the eye. While the difference may seem academic and of anatomical interest only, the importance is that branches of the facial artery can run in the base of the nasojugal groove as they pass up the face towards the inner corner of the eye. This region should only be treated, therefore, by highly skilled specialists with considerable treatment experience and anatomical understanding.

Some individuals can develop a diffuse depression or concavity under the eyes commonly referred to as an ‘under-eye hollow’ (essentially where a tear trough and nasojugal groove appear as one). These hollows can affect the way light reflects from the surface of the skin, creating under-eye shadows. They also often have dark circles due to the skin being thinner and more translucent, which allows the underlying veins carrying purplish-blue blood to show more as they are closer to the surface (a ‘Tyndall Effect’). The blood vessels themselves also tend to be more dilated with sluggish circulation leading to a degree of pooling of the dark venous blood. Dark circles can also be caused by having increased melanin pigment in the skin around the eye (periorbital hyperpigmentation), either through a genetic predisposition (familial or ethnic) or due to prolonged sun exposure. Certain medical conditions such as iron-deficiency anaemia and under-active thyroid can also be associated with developing dark circles, as are a lack of sleep and dehydration, which can cause a thinning of the delicate under-eye skin.

Cosmetic filler injections can greatly improve dark circles caused by shadows from tear troughs and under-eye hollows by indirectly repositioning the cheek fat pads upwards and directly filling out the depressions recreating a smooth contour transition between eyelids and cheek and reducing the under-eye shadows. Furthermore, by increasing the volume and therefore, the distance between the skin and underlying blood vessels, fillers can also reduce the visibility of the dark venous blood and hence also reduce the dark circles. Patients with dark circles caused by increased pigmentation often require additional treatment with professional medical-grade skincare. These include tyrosinase inhibitors, which block a key enzyme involved in the production of the melanin pigment, as well as antioxidants and broad-spectrum sunscreen that help protect against sun and other environmental exposure (which can damage the skin and stimulate overproduction of the pigment). These skincare products often also contain ingredients such as caffeine that help to improve the circulation of the blood in the under-eye area and reduce the contribution of the venous blood to the dark circles. 

The eyeballs are surrounded and protected by pockets of fat that act as cushions against the hard bony surface of the inner eye sockets. These fat pockets are separated into discrete compartments behind the upper and lower eyelids, where they are held in place inside the eye sockets by overlying skin, muscle and connective tissue (orbital septum). In some patients, this skin and soft tissue barrier that holds the fat compartments in place can begin to weaken allowing the fat to bulge forwards (pseudo-herniate) and form lower eyelid eyebags (palpebral bags). These patients often have generalised thinning and volume loss with under-eye hollowing as well as dark circles, which can make the eyebags appear even more prominent and unsightly. Surgical correction of the eyebags is called a lower blepharoplasty where the protruding fat pockets are either cut out or repositioned, and the overlying skin and soft tissue is tightened with sutures to push back the remaining fat and prevent further bulging. This may also be combined with fat grafting for volume correction and additional treatments such as laser resurfacing procedures to improve the skin envelope.

Cosmetic fillers based on hyaluronic acid gel can be used to improve the appearance of mild to moderate eye bags without the need for surgery with potentially remarkable results. The basic concept of filler treatment is fundamentally different from a surgical lower blepharoplasty in that it is the area around the eye bags that is being treated rather than the eyebags themselves. By improving the structural support in the mid-cheek area and correcting under-eye hollows through volume replacement, the projection of the soft tissue surrounding the eyebags can be improved, in effect concealing or hiding the eyebags.  The results from modern cosmetic fillers in this area can last for a considerable period of time, and progressively less filler is needed with each repeat treatment. Furthermore, there is substantially less downtime and risk of significant complications than with surgery.

Nevertheless, this is a highly specialist procedure, and correct patient selection is crucial as patients with severe eyebags, considerable skin and muscle laxity or a degree of localised tissue oedema (swelling) can have poorer treatment outcomes and are therefore not suitable. Furthermore, unlike surgery, the bags themselves are not directly treated but rather are hidden by treating the surrounding areas and therefore, they may continue to deteriorate with time in some individuals. Nevertheless, the ability to treat eye bags without the need for surgery but with potentially excellent results represents a significant advancement in periorbital aesthetics and a great alternative for many patients.

Volume loss in the upper eyelids at the junction with the brow can lead to ‘infra-brow hollowing’ with increased visibility of the bony border of the upper eye socket (orbital rim) and deepening of the sulcus.  These changes lead to the loss of the curved smooth, soft tissue contour normally associated with youthfulness, which is sometimes referred to as an “A-frame” deformity due to the slightly acute angle that forms in the soft tissue towards the middle of the orbital rim. The eyes can begin to appear sunken or recessed, and give the impression that the eyes are rounder and narrower, all of which are classic signs of ageing in the eye area. However, these changes can also result from a surgical upper eyelid blepharoplasty, where an excess amount of fat has been removed leading to increased visibility of the bony orbit.

Cosmetic fillers can be used to replace lost volume in the upper eyelid hollowing and re-establish a more youthful smooth curved contour by injecting a low density filler along the superior orbital rim using a cannula. This treatment can result in quite a significant improvement in the periorbital aesthetic appearance. Furthermore, the results can be long lasting, with some patients noticing continuous improvement even after two to three years.