Pterygium

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management

Definition

Pterygium is a benign, fibrovascular growth of conjunctival tissue extending onto the cornea, often associated with prolonged UV exposure and environmental irritants.

Aetiology

  • Chronic UV exposure.
  • Environmental irritants (e.g., wind, dust, sand).
  • Genetic predisposition.
  • Dry eye syndrome.

Pathophysiology

  • UV radiation induces conjunctival epithelial proliferation and fibrovascular changes.
  • Chronic irritation leads to inflammation and tissue remodelling.
  • Progressive growth may encroach onto the visual axis, causing astigmatism or vision impairment.

Risk Factors

  • Prolonged sun exposure (common in tropical climates).
  • Outdoor occupations (e.g., farmers, fishermen).
  • Chronic eye irritation (dust, wind, smoke).
  • Older age.
  • Male sex (higher prevalence).

Signs and Symptoms

  • Wing shaped growth on the conjunctiva extending onto the cornea.
  • Redness and irritation.
  • Foreign body sensation.
  • Dryness and tearing.
  • Blurred vision if encroaching on the cornea.
  • Progressive astigmatism due to corneal distortion.

Investigations

  • Slit-lamp examination: assesses lesion size, vascularisation, and corneal involvement.
  • Corneal topography: evaluates astigmatic changes.
  • Anterior segment OCT: for detailed assessment of corneal involvement.
  • Histopathology (if suspicious features present): to rule out ocular surface neoplasia.

Management

1. Conservative Management:

  • Artificial tears for symptom relief.
  • UV protection (sunglasses, wide brimmed hats).
  • Topical lubricants and mild steroids for inflammation control.

2. Surgical Intervention:

  • Indications for surgery:
    • Visual axis involvement.
    • Progressive growth causing significant astigmatism.
    • Cosmetic concerns.
  • Excision with conjunctival autograft: preferred surgical approach to reduce recurrence.
  • Mitomycin C or amniotic membrane graft: used in cases with high recurrence risk.

3. Referral:

  • Ophthalmology: if significant corneal involvement, rapid progression, or visual disturbance.
Eye DiseasesmypanotesPterygium