Quantification of blood-aqueous barrier breakdown after trabeculectomy: Pseudoexfoliation versus primary open-angle glaucoma

Purpose: Impairment of the blood-aqueous barrier in unoperated eyes with ps eudoexfoliation syndrome has been demonstrated by fluorescein angiography, fluorophotometry, measurement of aqueous flare, and determination of aqueou s protein. We performed noninvasive quantification of aqueous flare using t he laser flare-cell meter to compare blood-aqueous barrier breakdown after trabeculectomy in eyes with primary open-angle glaucoma (POAG) and in eyes with pseudoexfoliative glaucoma (PEX). Methods: Twenty eyes with PEX and 20 eyes with POAG were included in the st udy. Trabeculectomy was performed by two surgeons according to a standard t rabeculectomy technique. Intra- and postoperative treatments were identical in both groups. Aqueous flare was quantitatively determined using the lase r flare-cell meter FC-1000 (Kowa, Tokyo, Japan) before and 3, 5, 7, and 9 d ays after trabeculectomy. Absolute flare and difference between post- and p reoperative flare values were statistically analyzed using the Mann-Whitney U-Test for independent samples. Results: Before surgery, aqueous flare values were significantly higher in PEX than in POAG. On days 3, 5, 7 and 9 after surgery, flare values were si gnificantly higher in eyes with PEX than in eyes with POAG. Absolute differ ences between post- and preoperative flare values also were significantly h igher in eyes with PEX, but this was not true for percentage values. Conclusion: These results show that substantial blood-aqueous barrier break down occurs in eyes with PEX after trabeculectomy. These alterations may co ntribute to early or late complications of trabeculectomy and indicate the need for close postoperative follow-up evaluation in eyes with PEX.