Preclinical diagnosis of pseudoexfoliation syndrome

Although the diagnosis of pseudoexfoliation syndrome (PXS) is made by observation of pseudoexfoliation material (PXM) deposited on the anterior lens capsule, there are several additional signs related to pigment dispersion that are often present both in eyes with PXS and fellow eyes in unilateral cases. On the basis of the presence of these signs, we have categorized a group of patients as "pseudoexfoliation suspects" who demonstrated no evidence of PXM on the lens capsule in either eye. As PXM has previously been identified in the conjunctiva of affected eyes as well as fellow eyes in unilateral cases, we hypothesized that it could also be present in PXS suspect eyes. Inferior bulbar conjunctival biopsies were performed on four eyes with PXS, five fellow eyes, and 23 PXS suspect eyes, and specimens were examined by transmission electron microscopy. In eight PXS suspect eyes biopsy specimens demonstrated PXM, suggesting that PXS is more prevalent and possibly responsible for a greater proportion of glaucoma than previously suspected.