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INTRODUCTION
Dark circles are one of the most common dermatological complaints. The condition is also called periorbital melanosis, periorbital skin hyperpigmentation and infraorbital darkening. Dark circles are defined as unaesthetic blemishes around the eyes, especially at the lower eyelid. This condition is frequently seen in both men and women of all ages. Despite occurring in children and being more prevalent in certain ethnic groups (Middle Eastern and Mediterranean backgrounds), dark circles can be interpreted as an age-related change, since smooth skin around the eyes – the thinnest skin in the body – and skin color uniformity are the main attributes related to perceived age. The physiopathology of dark circles is not yet completely understood.
Three different factors may contribute to the clinical picture of this condition, alone or in combination:
- 1.
Shadows: shadowing is secondary to convexity of the lower eyelid, which in turn is caused by the bulge of the eye, lower lid fat prolapse or excess depth of the nasojugal groove (known more recently as tear trough deformity)( Fig. 11.1 ).
Fig. 11.1
Shadowing secondary to the bulging contour of the lower lid (nasojugal groove).
- 2.
Vessels: a bluish color is secondary to the subcutaneous venous network ( Fig. 11.2 ) while a reddish color is secondary to the visible dermal capillary network ( Fig. 11.3 ).
Fig. 11.2
Bluish color secondary to the subcutaneous venous network.
Fig. 11.3
Reddish color secondary to the visible dermal capillary network.
- 3.
Pigment: the brown color commonly seen in this condition is secondary to superficial melanin ( Fig. 11.4 ) while a brown-blue color is secondary to dermal melanin. These can be more easily seen under a Wood’s lamp ( Fig. 11.5 ).
Fig. 11.4
Brown color secondary to hyperpigmentation of the periorbital area.
Fig. 11.5
Patient with slight dark circles. A , Clinical aspect of patient with slight dark circles. B , UV picture of the same patient showing hyperpigmentation in the periorbital area.
Other etiologic factors are also reported for dark circles, including postinflammatory hyperpigmentation secondary to atopic or allergic contact dermatitis and periorbital edema.
The lower eyelid skin is very thin, and alterations in the blood flow supplying this area can worsen dark circles. Aging, expressed by changes in the pigmentation of the skin, loss of elasticity, worsening of the nasojugal groove and more visible vessels under the skin, can also aggravate the appearance of dark circles.
Very few studies have been published on dark circles, one possible reason being the difficulty in measuring the condition. Ohshima and Takiwaki analyzed dark circles quantitatively using various bioengineering techniques. Two kinds of reflectance meters and image analysis were used to measure erythema index (EI), melanin index (MI) and oxygenation index (OX) in subjects with and without dark circles. Also, the thickness and echo density of the dermis were evaluated using ultrasound echo images. Evaluation of EI and MI by image processing methods also seems suitable for quantitative evaluation of dark circles of the lower eyelid. Dermal thickness of the eyelid skin may also be involved in the appearance of dark circles.
There are also few published studies on the treatment of dark circles in the indexed literature. Proposed treatments usually involve a combination of different techniques: topical therapy, dietary supplements, peelings, fillers, autologous platelet-rich plasma rejuvenation, lasers, carbon dioxide therapy and surgery, and these should be directed to the local skin alterations (blood vessels, pigments, nasojugal groove and surface irregularities). They can be used alone or in combination, according to the patient’s needs ( Figs 11.1–11.5 ).
TOPICAL THERAPY
Many active ingredients of commercial products for the treatment of dark circles have not yet been studied to prove their real efficacy. These products generally contain antioxidants, bleaching agents, moisturizers and stimulants of new collagen formation.
A multicenter study investigated an eye cream containing a proprietary mixture of human growth factors and cytokines in combination with caffeine, bisabolol, glycyrrhinic acid and sodium hyaluronate for periorbital rejuvenation. The study revealed that some clinical signs of aging, including dark circles, showed significant improvement after 6 weeks of twice-daily application, with excellent tolerability.
A study showed that the use of vitamin K combined with retinol 0.15% for the treatment of periorbital hyperpigmentation was effective in 93% of patients. Another study evaluated a gel containing 2% phytonadione, 0.1% retinol and 0.1% vitamins C and E, which was moderately effective in reducing dark circles when applied twice daily to the lower eyelid site for 8 weeks in healthy Japanese adults.
Cosmetic camouflage, an opaque make-up, is very helpful for patients, especially women, who are familiar with these types of products. Camouflage make-up is usually creamy and comes in a variety of shades to match the natural skin color. Sometimes it is blended with color correctors to achieve a good color match and conceal dark circles.
DIETARY SUPPLEMENT
One study has evaluated the effects of a dietary supplement containing soy extract, fish protein polysaccharides, extracts from white tea, grape seed and tomato, vitamins C and E as well as zinc and chamomile extract on the skin of post-menopausal women. The evaluation after 3 and 6 months of treatment showed significantly greater improvement of skin conditions in the active group in a variety of parameters, including dark circles. This was the first study evaluating the effect of dietary supplements on dark circles, but it may be the beginning of a new research treatment field.
CHEMICAL PEELING
Despite little support in the literature, chemical peeling can be helpful for dark circles. It acts through exfoliation, abrasion and the shedding of superficial skin cells and layers, reducing pigmentation and wrinkles of the skin ( Fig. 11.6 ) around the eyes, significantly improving some cases of dark circles. The choice of the agent, concentration, number of applications and other factors will depend on each patient’s needs. The most frequently used peels for dark circles are trichloroacetic acid (TCA) and phenol peels. For further information see Chapter 4 .
