What causes bilateral lower eyelid and malar (cheekbone area) discoloration?

Bilateral Lower Eyelid and Malar Discoloration: Causes and Evaluation

Bilateral lower eyelid and malar discoloration is most commonly caused by periorbital hyperpigmentation (POH), which results from constitutional/genetic factors, vascular congestion, postinflammatory changes, or shadowing from anatomic structures, with the vascular type being most prevalent (41.8% of cases) followed by constitutional type (38.6%). 1

Primary Etiologic Categories

Constitutional/Genetic Periorbital Hyperpigmentation

• Most common in individuals of Indian and Malay descent, presenting as bilateral symmetric darkening of the lower eyelids extending to the malar region 1
• Results from increased melanin deposition in the epidermis and dermis, often hereditary in nature 2
• This type shows epidermal hyperpigmentation on histopathology with increased melanocytic activity 3

Vascular Periorbital Hyperpigmentation

• Predominant type overall (41.8%), most frequently seen in Chinese populations 1
• Caused by excessive vascularity and periorbital edema creating a bluish-purple discoloration 2
• The thin periorbital skin allows visualization of underlying vascular structures, creating the appearance of darkening 4

Postinflammatory Hyperpigmentation

• Accounts for 12% of POH cases and results from prior inflammation or dermatitis 1
• Atopic dermatitis and allergic contact dermatitis are key triggers, causing secondary hyperpigmentation in the periorbital region 2
• Associated with chronic rubbing, scratching, or irritation from topical products 4

Dermatologic Conditions with Malar Involvement

Rosacea presents with characteristic malar rash, facial erythema, telangiectasias, papules, pustules, and prominent sebaceous glands, which can extend to the periorbital area 5

Melasma can involve the malar region in its characteristic patterns (centrofacial, malar, or mandibular distribution), though typically spares the immediate eyelid margin 3, 6

Anatomic/Structural Causes

• Shadow effects from skin laxity and tear trough deformity account for 11.4% of cases, particularly with aging 1
• Floppy eyelid syndrome causes upper eyelid edema but can create secondary changes affecting lower lid appearance through chronic irritation 5

Critical Diagnostic Distinctions

Inflammatory/Infectious Causes to Exclude

Allergic conjunctivitis presents with bilateral eyelid edema, conjunctival injection, and watery/mucoid discharge—but this is acute rather than chronic discoloration 7

Medication-induced keratoconjunctivitis shows bilateral conjunctival injection with contact dermatitis of eyelids (erythema and scaling), particularly with topical glaucoma medications, NSAIDs, or preservatives 5, 8

Chronic blepharitis may cause eyelid margin changes but typically presents with crusting, telangiectasias, and meibomian gland dysfunction rather than malar extension 5

Evaluation Approach

Clinical Examination Priorities

Examine the skin for rosacea features: rhinophyma, erythema, telangiectasia, papules, pustules, and hypertrophic sebaceous glands in malar areas 5

Assess pigmentation pattern: constitutional POH shows uniform bilateral darkening, vascular type has bluish hue, postinflammatory shows irregular patches 1

Wood's lamp examination differentiates epidermal (pigment enhancement) from dermal (no enhancement) or mixed types of hyperpigmentation 3

Mexameter measurement objectively quantifies the extent and severity of periorbital hyperpigmentation 1

Historical Red Flags

• Recent medication changes (topical eye drops, systemic agents like megestrol acetate) 8
• History of atopic dermatitis, allergic rhinitis, or chronic eye rubbing 2
• Sun exposure patterns and use of cosmetics 3
• Family history of similar pigmentation (constitutional type) 2

Common Pitfalls

Do not assume all bilateral periorbital darkening is benign constitutional hyperpigmentation—medication-induced causes require discontinuation of the offending agent 8

Avoid missing underlying rosacea, which requires specific management including eyelid hygiene and potential systemic therapy for ocular involvement 5

Do not overlook postinflammatory causes that may respond to treatment of the underlying dermatitis rather than depigmenting agents alone 2, 6