ABSTRACT
Objective To observe the histopathologic and ultrastructural characteristics of cornea and adjacent conjunctiva in Mooren’s ulcer. Methods The samples of limbal and central cornea and adjacent bulbar conjunctiva taken from active Mooren’s ulcer after lamellar keratoplasty were cut into paraffin sections and ultrathin sections and observed by light and transmission electron microscopy. The samples taken from patients of a Terrien’s marginal degeneration and a bacterial corneal ulcer were used as controls. Results Chronic inflammation including lymphocytes and plasma cells infiltrating existed in bulbar conjunctiva and sclera of Mooren’s ulcer. Limbal corneal epithelium, Bowman’s membrane, anterior stroma and adjacent superficial sclera melted and the inferior stromal collagen disorganized. The epithelial basement membrane of ulcer progressive edge had been destroyed while the epithelium and stroma kept quiescent. Lymphocytes infiltrated in conjunctiva and corneal epithelium of Terrien’s marginal degeneration with normal epithelial basement membrane, while Bowman’s membrane was destroyed. The epithelial basement membrane of bacterial corneal ulcer was intact. Conclusion Bulbar conjunctiva may act as a local lymph node of Mooren’s ulcer. Epithelial basement membrane of Mooren’s ulcer may have some abnormality as it was invaded first during ulcer progressing and it’s valuable to have a further study.