Damage to the blood-aqueous barrier in eyes with primary angle closure glaucoma

PURPOSE: This study investigates the inflammation in the anterior chamber in eyes with primary angle closure glaucoma (PACG) and evaluates the effect of intraocular pressure (IOP) elevation on the blood-aqueous barrier (BAB). METHODS: Thirty-five patients (35 eyes) with acute primary angle closure glaucoma (APACG), 42 patients (42 eyes) with chronic primary angle closure glaucoma (CPACG), and 50 age-matched healthy controls (50 eyes) were included in this study. The flare value and cell counts were quantified using laser flare cell photometry. Statistical analysis was performed to compare differences in flare value and cell counts between different groups and explore the relation between the inflammation and IOP. RESULTS: The mean flare value (photon counts per millisecond, ph/ms) in the APACG, CPACG, and healthy control group was 141.4±123.1, 7.7±4.1, and 4.5±1.1, respectively. The mean cell counts (cells/0.5 mm(3)) in the three groups were 126.0±67.8, 5.2±5.8, and 0.8±0.7, respectively. The flare value and cell counts in both the APACG group and the CPACG group were significantly higher than those in the healthy control group (p<0.001). Furthermore, the flare value and cell counts in the APACG group were significantly higher than those in the CPACG group (p<0.001). There were positive correlations between the IOP level and flare value (r=0.527, p<0.001), and cell counts(r=0.775, p<0.001), respectively, in the APACG group. CONCLUSIONS: Disrupted BAB and inflammation in the anterior chamber were found in eyes with both kinds of PACG. The damage of BAB was more severe in eyes with APACG than those with CPACG. The IOP elevation, especially a dramatic IOP elevation, might be the factor responsible for the change of BAB in eyes with PACG.