THE HISTOPATHOLOGY AND THE MECHANISM OF ENTROPION IN PATIENTS WITH TRACHOMA

Background. Eyelids of patients with trachoma may be thickened. This t hickening could be attributed to trachomatous changes in the conjuncti va and tarsus. Methods: Biopsies of tarsal plates and palpebral conjun ctivae were obtained from 17 upper eyelids of 11 patients with inactiv e trachoma who underwent posterior tarsotomy procedures for entropion repair. Results: Light microscopy studies showed a thick and compact s ubepithelial fibrous membrane adherent to the tarsal plate. This membr ane caused apparent thickening of the tarsus when measured intraoperat ively (range, 1.25-2.00 mm). Other histopathologic findings include at rophy of the meibomian glands with thickening of the acinar basement m embrane, loss of goblet cells, retention cysts, and hyaline degenerati on of the tarsal plate with focal replacement by adipose tissue. Concl usion: The contraction of the subepithelial fibrous membrane formed by vertically oriented parallel collagen fibers is one of the main facto rs contributing to the entropion formation.