Changes in peripapillary blood flow after dorzolamide 2%/timolol 0.5% versus latanoprost 0.005%/timolol 0.5% using optical coherence tomography angiography

Purpose: The purpose is to compare the changes in the peripapillary blood flow in primary open-angle glaucoma (POAG) after administration of dorzolamide 2%/timolol 0.5% fixed combination versus latanoprost 0.005%/timolol 0.5% fixed combination, using spectral-domain optical coherence tomography angiography (OCTA). Patients and Methods: In this prospective, comparative, nonrandomized study, patients with POAG received simultaneous treatment with dorzolamide 2%/timolol 0.5% fixed combination in the right eye (Group 1) and latanoprost 0.005%/timolol 0.5% fixed combination in the left eye (Group 2) for 1 week. Intraocular pressure (IOP) was measured using applanation tonometry; and peripapillary capillary density and retinal nerve fiber layer (RNFL) thickness was assessed using OCTA before starting treatment and 1 week after the treatment. Results: IOP reduction was superior in Group 2; however, this was not statistically significant. Both groups showed an increase in the peripapillary capillary density and RNFL thickness after 1 week of the treatment as evaluated by OCTA angiography. However, this increase was not statistically significant. There was only a statistically positive correlation between IOP reduction and increase in the superior-hemiradial peripapillary capillary density (P = 0.037) in Group 1 and between IOP reduction and increase in the total RNFL thickness and superior hemi-RNFL thickness (P = 0.044, 0.032, respectively) in Group 1. Conclusion: Intraocular pressure decreased in both groups with no significant difference between both groups. There was more increase in radical peripapillary capillary density and RNFL thickness following treatment in dorzolamide 2%/timolol 0.5% group compared to the other groups; however, the difference between the two groups was not statistically significant.