Long-term effects of prostaglandin analogues on the anterior chamber depth of patients with primary open-angle glaucoma.

Objective: To evaluate the effect of long-term application of bimatoprost and latanoprost on the anterior chamber depth of primary open-angle glaucoma patients.

Methods: The anterior chamber depth (ACD) and axial length (AL) of patients using prostaglandin analogues for open-angle glaucoma (group I) and an age- and gender-adjusted control group (group II) were measured by ultrasonography. Patients using bimatoprost and those using latanoprost were also compared in terms of ACD and AL.

Results: The mean ACD of group I (27 eyes of 27 subjects) was significantly lower than that of group II (30 eyes of 30 subjects) (p = .012). Similarly, the ratio of ACD to AL was significantly lower in group I compared with group II (p = .001). The ACDs of patients using bimatoprost or latanoprost and the control group were not significantly different by Kruskal-Wallis test (p = .056), but the differences of these 3 groups in ACD/AL ratios were significant (p = .004). When the Mann Whitney U test was used for pairwise comparison, there was a significant difference between the control group and the patients using latanoprost or bimatoprost in terms of the ACD/AL ratio (p = .008 for each). There was no difference between the patients using latanoprost and those using bimatoprost in terms of the ACD/AL ratio (p = .4).

Conclusion: The ACD of patients on prolonged therapy with prostaglandin analogues seems to be lower than than that of the control group. However, prospective long-term studies on large number of subjects are needed to evaluate the effect of each type of prostaglandin on ocular structures.