OcuLearning › Conjunctiva

Pterygium/Pinguecula

ROUTINE — Conjunctiva

Symptoms

  • irritation, redness, and foreign body sensation
  • blurred vision if the lesion induces astigmatism or blocks the visual axis
  • cosmetic concern (yellowish bump or fleshy "wing" on the eye)
  • often asymptomatic until inflamed by wind, dust, or uv

Clinical Findings

Location

  • interpalpebral fissure: almost always at the 3 or 9 o’clock position
  • nasal predominance: UV reflected from the nose concentrates on the nasal limbus

Pinguecula

  • yellow-white, fleshy conjunctival lesion adjacent to the limbus
  • key: does NOT cross the limbus or involve the cornea

Pterygium

  • triangular, fibrovascular tissue that crosses the limbus onto the cornea
  • stocker’s line: yellow-brown iron line on the cornea ahead of the leading edge (indicates stability)
  • induced astigmatism: flattening of the cornea (with-the-rule) as it grows

Complications

  • delle: localized corneal thinning/drying adjacent to an elevated lesion
  • inflammation: focal injection and dilated "feeder" vessels

Etiology

Risk factors

  • chronic UV/sunlight exposure (the primary driver)
  • environmental irritants: wind, dust, sand, and heat
  • epidemiology: most common in equatorial "pterygium belt" regions

Red Flags

  • rapid growth or atypical location (superior/inferior): suspect ossn or cin
  • corkscrew vessels or gelatinous surface: suggests ocular surface squamous neoplasia
  • visual axis encroachment: requires surgical intervention to prevent permanent vision loss
  • restricted motility: if the "pterygium" tethers the eye, consider symblepharon

Investigations

Slit lamp exam

  • measure the distance from the limbus to the leading head (cap) for monitoring
  • check for a stocker line and assess the underlying corneal thickness (rule out delle)

Topography

  • essential for documenting irregular astigmatism caused by corneal distortion

Histopathology

  • mandatory: send every excised specimen to pathology to rule out occult malignancy (ossn)

Treatment

Conservative

  • preservative-free artificial tears: 4–8x/daily
  • mild steroids (e.g., fml or loteprednol): for short-term control of inflamed flares

Surgical (standard of care)

  • excision with conjunctival autograft (cag): graft from the superior bulbar conjunctiva
  • cag reduces recurrence from ~40% (bare sclera) to ~5%
  • amniotic membrane: used if the patient needs to save conjunctiva for future glaucoma surgery

Adjuvants

  • mitomycin c (mmc): used intraoperatively for high-risk recurrent cases

Clinical Pearl

a pterygium that crosses 3–4 mm onto the cornea or induces astigmatism should come off — removal with a conjunctival autograft drops recurrence to ~5% and preserves surface biology.

Differential Diagnosis

  • • cin/ossn (look for gelatinous, white, or vascular surface)
  • • pseudopterygium (adhesion from prior trauma or chemical burn; can occur anywhere)
  • • phlyctenule (inflammatory nodule; usually responds rapidly to steroids)
  • • conjunctival melanoma or pam (pigmented lesions)

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