(dark circles)

Periorbital pigmentation

Periorbital hyperpigmentation (POH), also known as periocular hyperpigmentation, periorbital melanosis, dark circles, infraorbital darkening, infraorbital discoloration, or idiopathic cutaneous hyperchromia of the orbital region, is a common condition encountered in dermatology practice. It is an ill-defined entity that presents as bilateral round or semicircular homogenous brown or dark brown pigmented macules in the periocular region. It can affect an individual’s emotional well-being and influence quality of life. At Akiya Aesthetics, Dr. Rupika Singh offers Dark Circles Treatments in Ghaziabad & Delhi.

There is scarcity of data regarding the incidence and prevalence of POH due to its transitory nature and lack of reasonable etiological explanation. In an Indian study, it was found that POH was most prevalent in the age group of 16 to 25 years (i.e., 95 out of 200 patients [47.50%]). Among the 200 patients studied, it was more prevalent in women (162 [81%]) than men and the majority of the affected women were housewives (91 45.50%])

Clinically, POH is characterized by light- to dark-colored, brownish-black pigmentation surrounding the eyelids. It gives a tired look to the patient. Diagnosis is mainly based on clinical examination. It is important to differentiate the dark eyelid skin with shadowing due to tear trough. Manual stretching of the lower eyelid skin can help to differentiate between true pigmentation and shadowing effect. Although the former retains its appearance with stretching, the latter improves or resolves entirely. An increase in violaceous discoloration on manual stretching of the lower eyelids is due to thin eyelid skin or hypervascularity of lower eyelid.

Causes

Periorbital hyperpigmentation is considered to have a genetic basis. Goodman and Belcher reported many families with pigmentation around the periorbital area in several members of the family. Some were mildly affected and some severely affected.

Periorbital pigmentation due to dermal melanocytosis. Dermal melanocytosis is characterized by the presence of melanocytes in the dermis. Clinically, these lesions are recognizable by their distinctive grey or blue-grey appearance. Dermal melanocytosis causing periocular hyperpigmentation can be due to congenital or acquired causes.Dermal melanocytosis can be placed into the pigmentary class of Huang et al’s classification.

Postinflammatory hyperpigmentation. Excessive pigmentation can also be due to postinflammatory hyperpigmentation secondary to atopic and allergic contact dermatitis and other dermatological conditions (e.g., lichen planus pigmentosus) and can be drug induced, such as in the case of fixed drug eruptions and erythema dyschromium perstans. Periorbital hyperpigmentation can be caused by rubbing and scratching of skin around the eyes and by accumulation of fluid due to allergy as in atopic dermatitis and allergic contact dermatitis.

Superficial location of vasculature. Superficial location of vasculature and thin skin overlying the orbicularis oculi muscle is another common cause of periorbital hyperpigmentation. This condition usually involves the entire lower eyelids with a violaceous appearance due to prominent blood vessels covered by a thin layer of skin, more in the inner aspect of the eyelid, and is usually accentuated during menstruation. When the lower eyelid is manually stretched, the area of darkness spreads out without blanching or significant lightening and results in deepening of violaceous color, which could be used as a diagnostic test to confirm the vascularity.

Tear through depression. Tear troughs represent an anatomical location that becomes depressed with age, centered over the inferior-medial orbital rim. It is an age-related change. It occurs mainly because of loss of subcutaneous fat and thinning of overlying skin of the orbital rim ligaments, combined with cheek descent, conferring hollowness to the orbital rim area. A combination of the hollowness and the overlying pseudo herniation of the infraorbital fat accentuate the shadowing in the tear trough causing dark circles, depending on the lighting condition.

Periorbital edema. The eyelid region has a spongy property, which can lead to fluid accumulation due to systemic and local causes. Diagnostic features that suggest edema includes worsening in morning or after eating salty meals. The history of variability in intensity and extension is important to determine the influence of edema on periorbital hyperpigmentation. When compared with normal orbital fat, edema is still present in downward gaze and does not change much in upward gaze.

Extension of pigmentary demarcation lines of face. Pigmentary demarcation lines (PDL) are borders of abrupt transition between hyperpigmented skin and lighter areas. According to the site, they have been labelled A to H lines. F and G types are present over the lateral side of orbit and present as V-shaped and W-shaped patches, respectively.In a study by Malakar et al, 100 Indian patients with a diagnosis of POH were evaluated. Their results showed that in 92 percent of study patients, periorbital melanosis was an extension of the pigmentary demarcation line over the face.

Ocular hypotensive drugs. Prostaglandin analogues, such as latanoprost and bimatoprost, which are used as ocular hypotensive eye drops in patients with glaucoma, can also cause periorbital hyperpigmentation.Patients develop periocular hyperpigmentation most frequently between 3 to 6 months of initiating bimatoprost procedure. Complete reversal of pigmentation occurs after discontinuation of bimatoprost. It was reported that the increased melanogenesis in dermal melanocytes and increased transfer of melanin granules to basal epidermis is the likely mechanism of bimatoprost-induced hyperpigmentation.

Environmental Causes–Ultraviolet radiation aggravates POHand some lifestyle factors may contribute to developing POH, including lack of sleep, stress, alcohol overuse, and smoking, although not clinically substantiated.