What is a pterygium?

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What is a Pinguecula?

A pinguecula is a benign, yellowish, elevated conjunctival lesion that occurs on the bulbar conjunctiva adjacent to the limbus but does NOT cross onto the cornea, distinguishing it from its related condition, pterygium.

Key Distinguishing Features from Pterygium

The critical difference is that pinguecula remains confined to the conjunctiva, while pterygium is a fibrovascular growth that crosses the limbus and extends onto the cornea. 1, 2

Pterygium Characteristics (for comparison):

  • Triangular conjunctivo-epithelial overgrowth that proliferates from the bulbar conjunctiva and invades the corneal surface 3
  • Crosses the limbus and extends onto the peripheral cornea, potentially reaching the optical zone 1, 4
  • Can cause significant visual complications including corneal astigmatism and vision impairment 1, 2

Shared Etiology

Both pinguecula and pterygium share similar risk factors:

  • Chronic ultraviolet (UV) radiation exposure is the primary pathogenic factor 1, 2, 4
  • Environmental irritants including heat and dust 3
  • Potential viral infection involvement 2, 3
  • Tear film abnormalities and immunologic disturbances 2

Clinical Significance

Pinguecula:

  • Typically asymptomatic and cosmetic in nature
  • May cause mild irritation or dry eye symptoms
  • Does not require surgical intervention unless symptomatic

Pterygium (when it progresses):

  • Initially asymptomatic but can develop dry eye manifestations (burning, itching, tearing) 2
  • Surgical treatment is indicated when: visual acuity is compromised, progressive astigmatism develops, the lesion approaches the optical axis, or significant ocular surface discomfort occurs 5, 4
  • Can cause diplopia or strabismus as a surgical complication due to medial rectus damage or scarring 6, 7

Prevention

Long-term UV protection is essential for both conditions to prevent development and progression 5, 4

References

Research

Update on overview of pterygium and its surgical management.

Journal of population therapeutics and clinical pharmacology = Journal de la therapeutique des populations et de la pharmacologie clinique, 2022

Research

[Pterygium: etiology, pathogenesis, treatment].

Vestnik oftalmologii, 2017

Research

Pterygium: histological and immunohistochemical aspects.

Romanian journal of morphology and embryology = Revue roumaine de morphologie et embryologie, 2011

Research

[Pterygium: pathogenesis, diagnosis and treatment].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft, 2021

Research

[Pterygium. Etiology, clinical aspects and novel adjuvant therapies].

Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft, 2010

Guideline

Surgical Treatment of Pterygium

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Treatment of Pterygium with Adjunctive Therapies

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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