Infraorbital Hollow and Nasojugal Fold

Introduction

The eyes are the primary focal point of the face, playing important roles in conveying emotion and our perception of beauty. As the face ages, changes to the infraorbital region occur, negatively affecting our perception of beauty and potentially evoking emotions of sadness and fatigue. Consequently, periocular rejuvenation is a frequent patient request for aesthetic improvement.

The infraorbital hollow (IOH) refers to the curvilinear or U-shaped depression under the eyes from the nasal bone to the outer corner of the eye and comprises three core elements: the “tear trough” and “nasojugal fold” medially and the palpebromalar groove laterally ( Fig. 20.1 ). The terms “tear trough” and “nasojugal fold” have historically been used interchangeably. The tear trough occurs mildly in all people across all ages and refers to the superior aspect of the nasojugal fold. A sign of early aging, the deepening of the tear trough leads to a true indentation at the junction of the thin eyelid skin above and thicker skin of the cheek below. Later, the midcheek may descend, accentuating a flat or hollow crescent below the eye and lengthening of the lower eyelid. The appearance of hollows and dark circles under the eye is the interplay of various factors. Genetics, habits and environmental exposures lead to dyschromias and pigmentation changes, soft tissue laxity, subcutaneous volume alterations, changes in bone, and redistribution of superficial fat; all of which contribute to shadowed contours and deepening folds. Periorbital volumetric shifting and loss is not an isolated event but part of a global shift in the contours of the aging face.

There is minimal fat below the lower eyelid. The orbicularis oculi muscle has direct bony attachments to the orbital rim, from the nasal bone to the medial limbus. Laterally, orbicularis-retaining ligaments connect the deep surface of the skin to bone. Retaining ligaments weaken, facial bones recede, and volume decreases in the deep fat pads, causing the cheek to descend and superficial fat to prolapse below the eye, all of which combine with genetically predisposed discolorations and bony changes to contribute to the perception of hollowed and sometimes baggy eyes, deep and shadowed tear troughs, and an aged, fatigued appearance refractory to cosmetic attempts at concealment.

Treatment of the periorbital area with injectable agents allows little room for error. Optimal outcomes require careful patient selection, discriminating choice of filling agent, and precise techniques to avoid complications.

Candidates for Augmentation of the Infraorbital Hollow

Appropriate patient selection is critical and relies on careful medical and ophthalmic history and physical assessment. Poor candidates are unlikely to obtain optimal results, may not be satisfied with results, and are at higher risk of side effects such as visibility and irregularity ( Table 20.1 ). Patients with diseases or metabolic conditions that predispose to lower eyelid irregularity, bleeding, and infection should be excluded. All anticoagulant medications and supplements should ideally be discontinued if medically appropriate. Some patients have genetically determined pigmentation that may appear like a tear trough but without an indentation that can be filled. Pigmented dark lower eyelid circles cannot be improved by fillers and can indeed be worsened by treatment. Older patients with thinner, crepelike, inelastic skin and individuals with preexisting malar edema—whether metabolic (thyroid disease) or otherwise (chronic sinus disease, prior surgery, etc.)—may not respond well and also have an increased risk for adverse events and dissatisfaction with results. It is prudent to identify the ideal candidate for periorbital fillers in consultation. Patients with orbital fat herniation and significant skin laxity would benefit first from lower lid blepharoplasty with possible midface lift or other adjuvant procedures. Injection works best in patients with thick and smooth skin with a well-defined tear trough or defined maxillary retrusion or hypoplasia (commonly noted in young Asian females), without excessive prolapsed eyelid fat or excess eyelid skin. Lower eyelids should be evaluated for orbicularis hypertrophy, eyelid laxity and prolapsed orbital fat ( Table 20.2 ).

Appropriate Filling Agents

Thin skin directly overlying bone with ligamentous attachments allow any irregularity to be readily visible. Furthermore, the periocular treatment area is highly vascularized and maintains a high propensity for discoloration. The ideal filler is one with a low extrusion force or density to allow precise and delicate injection through lower-gauged needles or cannulas, and is reversible or, at the very least, biodegradable. Because there is a tendency for anything injected into this area to form visible lumps, particularly on facial animation, permanent fillers should be considered only with great caution. In fact, the eye muscles are the most active muscles in the body and consequently, fillers placed in this dynamic area have to seamlessly integrate and withstand the muscle movements.

Hyaluronic acid (HA)—with its gel consistency, varying concentrations and the possibility of dilution, favorable flow characteristics, fewer side effects, and nonpermanence—has emerged as the treatment of choice by many aesthetic physicians for periocular rejuvenation. Lumps or irregularities can be avoided with careful and precise injection techniques and can also be easily reversed with hyaluronidase injection, which is an important consideration when injecting in delicate areas requiring the most precise placement of fillers. Surprisingly, HA fillers in the periorbital region yield better than expected longevity. Lambros (and others) has described the persistence of effect, often in excess of 1 year. Donath et al. used three-dimensional imaging in 20 patients treated in the tear trough with HA and found an average 85% maintenance of effect at the final follow-up visit (average 14.4 months); the patient with the longest duration retained 73% volume augmentation at 23 months without any touch-ups. In practice, it is not uncommon to see persistence of HA filler effect for many years after it was originally placed. Common side effects with HA fillers may include nodules, a bluish tint (the Tyndall effect), along with injection- related bruising and swelling (see Complications section later). Additionally, given the proximity to the infraorbital artery, infratrochlear artery, dorsal nasal artery, and angular artery, there is a risk of vascular occlusion and even rarer, injection related visual adverse events.

Calcium hydroxylapatite (CaHA) has yielded positive outcomes in other areas of the face, and Hevia has detailed successful outcomes in the infraorbital region using CaHA diluted by 10% to 30% with 2% lidocaine. However, CaHA has a history of palpable (and sometimes visible) nodules, particularly in the lips, and Goldman has reported a case of superficial nodularity after injection of CaHA in the IOH. Its major drawback remains the lack of reversibility. Despite its biodegradable nature, if an adverse event occurs, there is little to do but wait until the product has naturally resorbed.