Histopathological Study of Primary Pterygium

Abstract

Background: A graded series of ocular surface changes has been described throughout the bulbar conjunctiva. The most advanced changes occurring directly over the pterygium surface, confirming that pterygium is indeed an ocular surface disorder. Purpose: Pterygium is characterized as invasive, proliferative fibro-vascular altered conjunctival tissue. The extensive vascular network is likely to significantly contribute to the progression of the disease. The present study aims to correlate the findings obtained from studying the epithelium of true primary pterygium by impression cytology technique and microscopic picture. Design: Prospective clinical study. Methods: This study is a prospective study designed to analyze data of 20 eyes of 20 patients presenting to the Department of Ophthalmology at "Ain Shams University" and at the "Research institute of ophthalmology" with clinically diagnosed pterygium. Results: Histopathological study identified pathological change in epithelium and subepithelial fibrovascular tissue of the pterygium. Conclusion: Histopathological examination of the epithelium of pterygia revealed epithelial changes most prominent directly above the head of pterygium.

Update on overview of pterygium and its surgical management

“…Stocker's line, which is iron deposition in the basal layer of the corneal epithelium in front of the cap, indicates the chronicity of pterygium. 1,14 Squamous metaplasia has also been observed in samples obtained from pterygium. 14 Histopathologically, pterygium is a collection of altered LSCs with centripetal growth, which is associated with metaplastic and hyperplastic epithelium, squamous goblet cells, disruption of Bowman's membrane with abundant active fibroblasts, stromal inflammation, neovascularization, and extracellular matrix metalloproteinases (MMPs) activities.…”

“…1,14 Squamous metaplasia has also been observed in samples obtained from pterygium. 14 Histopathologically, pterygium is a collection of altered LSCs with centripetal growth, which is associated with metaplastic and hyperplastic epithelium, squamous goblet cells, disruption of Bowman's membrane with abundant active fibroblasts, stromal inflammation, neovascularization, and extracellular matrix metalloproteinases (MMPs) activities. [15][16][17][18] Many histopathological features of chronic inflammation are also observed in pterygium.…”

“…13 The pterygium consists of three separate parts including cap, head, and body/tail. 14 The cap or front edge is a smooth area on the cornea that is mainly composed of fibroblasts that attack and destroy Bowman's membrane. The head is a vascular area located behind the cap and firmly attached to the cornea.…”

“…The presence of chronic inflammation in the pterygium is also caused by factors such as the presence of lymphocyte purification consisting of T lymphocytes, plasma cells, and mast cells; the increase of newly formed blood vessels and fibroblasts; the presence of degenerative collagen fibers; and the presence of abnormal elastic fibers. 14 The destructive effect of UV rays leads to the reduction of corneal LSCs, and subsequently causes limbal failure and activates tissue growth factors that cause angiogenesis and cell proliferation. The pterygium consists of fibrovascular tissue and its collagen fibers often show elastosis.…”

Changes of refractive status after pterygium surgery in a tertiary eye hospital in Bangladesh

“…2 A pterygium is histologically similar to pingueculum and shows elastotic degenerative changes in vascularized subepithelial stromal collagen. 3 Several mechanisms have been suggested to explain the induced astigmatism by pterygium. 4 The first mechanism includes pooling of the tear film at the leading edge of pterygium as the head of pterygium approach the apex of cornea a tear meniscus develops between the corneal apex and elevated pterygium causing an apparent flattening of corneal curvature.…”