What is the medical term for dark circles under the eyes?

Periorbital Hyperpigmentation: The Medical Term for Dark Circles Under Eyes

The medical term for dark circles under the eyes is periorbital hyperpigmentation (POH), also sometimes referred to as infraorbital dark circles or periocular hyperpigmentation 1.

Etiology and Pathophysiology

Periorbital hyperpigmentation is a multifactorial condition with several underlying causes:

1. Vascular factors:

   • Superficial location of blood vessels
   • Increased visibility of the orbital vascular network through thin eyelid skin
   • Vascular congestion

2. Pigmentary factors:

   • Dermal melanin deposition
   • Postinflammatory hyperpigmentation secondary to atopic or allergic contact dermatitis 2

3. Structural factors:

   • Periorbital edema
   • Tear trough deformity
   • Infraorbital fat pad protrusion or prolapse
   • Skin laxity causing shadowing 2, 3

4. Contributing conditions:

   • Allergic conjunctivitis
   • Atopic dermatitis
   • Rosacea conjunctivitis (associated with periorbital hyperpigmentation) 1

Clinical Presentation

Periorbital hyperpigmentation presents as:

• Bilateral, round, homogeneous pigment macules on the infraorbital regions 2
• May appear as "allergic shiners" in patients with allergic conditions 1
• Can be associated with eyelid edema in allergic conditions
• Often more pronounced in individuals with darker skin types 4
• May have a strong familial component, particularly in darker skin types 3

Evaluation

When evaluating a patient with periorbital hyperpigmentation, consider:

1. Underlying causes:

   • Allergic conditions (allergic conjunctivitis, atopic dermatitis)
   • Sleep disturbances
   • Nutritional deficiencies
   • Systemic disorders 4

2. Contributing factors:

   • Thin eyelid skin
   • Prominent vasculature
   • Tear trough deformity
   • Orbital fat prolapse 3

Treatment Options

Treatment approaches for periorbital hyperpigmentation include:

1. Topical treatments:

   • Topical retinoids (effective for pigmentary causes)
   • Topical hydroquinone (for melanin-related hyperpigmentation)
   • Vitamin C serums (for brightening and antioxidant effects)

2. Procedural treatments:

   • Platelet-rich plasma (PRP) injections (shown to be effective for periorbital dark circles) 1
   • Carboxytherapy (carbon dioxide therapy) - demonstrated superior efficacy compared to Nd:YAG laser 5
   • Hyaluronic acid fillers (for tear trough deformity) 3
   • Fractional lasers (for skin resurfacing and pigmentation)

3. Alternative treatments:

   • Ozone therapy has shown promising results in case reports 6

Important Considerations

• POH tends to progress over time without intervention, so early management is recommended 4
• Treatment should be tailored based on the predominant cause (vascular, pigmentary, or structural)
• Sun protection is essential for preventing worsening of hyperpigmentation
• Caution is needed with aggressive treatments as they may worsen hyperpigmentation, especially in darker skin types
• Addressing underlying allergic conditions or sleep disturbances may improve appearance

Treatment Efficacy

Recent evidence suggests:

• Carboxytherapy is significantly more effective than Nd:YAG laser for treating periorbital dark circles, with fewer side effects like erythema and post-inflammatory hyperpigmentation 5
• PRP treatment has shown promising results for periorbital dark circles, with improvements noted in 47.8% of patients at 3 months and 60.9% at 6 months 1
• For structural causes, specialized filler techniques using microdroplet subdermal placement can provide good aesthetic outcomes with low risk of complications 3

Periorbital hyperpigmentation remains a challenging condition to treat completely, but understanding its multifactorial nature allows for more targeted and effective management approaches.