A Histopathologic Study of the Iris in a Patient with Exfoliation Syndrome

ABSTRACT

The pathogenesis of the exfoliation syndrome is still unknown. To clarify the etiology of the exfoliation syndrome, we examined the iris taken from a patient with exfoliative glaucoma during cataract surgery using light microscope, polarization microscopy and electron microscopy. The amorphous substance around the iris pigment epithelium and stroma were stained purplish red in PAS staining and showed purplish red metachromasia in toluidine blue staining. In electromicroscopic examination, we observed that many fibrillar materials were deposited at basement membrane and partially detached basement membrane around the pigment epithelium of the iris. Therefore we concluded that the exfoliative materials in this syndrome is a sort of glycoprotein and originated from the abnormal synthesis and metabolism of the basement membrane in the eye.