Effect of Intraocular Pressure Lowering Treatment on Peripapillary and Macular Vessel Density on Normotensive Eyes with Optic Disc Drusen: A Randomized Controlled Trial

Abstract

ABSTRACT To evaluate the effect of intraocular pressure (IOP) reduction on peripapillary and macular vessel density parameters from optical coherence tomography angiography (OCT-A) in normotensive eyes with optic disc drusen (ODD). Randomized controlled trial, with 6 months of follow-up, including normotensive eyes with ODD divided into two groups: control group (lubricating eye drop) and case group (latanoprost 50mcg/ml). We used OCT-A to evaluate peripapillary and macular vessel density parameters. Data were collected at baseline and at 1, 3, and 6 months following the use of eye drops. This study included a total of 32 eyes (16 cases and 16 controls) from 19 patients. After 6 months, the group using latanoprost IOP reduced IOP to 10.8 ± 0.64 versus 13.5 ± 0.54 mmHg in the control group (p < 0.001). We observed significant changes in OCT-A vessel density peripapillary parameters. The total radial peripapillary capillary (RPC) density (%) at month 6, in the eyes using latanoprost was 55.1 ± 1.05% and control was 57.9 ± 0.88%, p = 0.033. However, no changes were observed in macular vessel density parameters as well as retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness between groups after 6 months of using latanoprost. No sight-threatening events were observed during follow-up in either group. Until now there is no evidence that just lowering IOP can benefit normotensive patients with ODD. In fact, we observed a significant decrease in RPC vessel density after 6 months of IOP reduction using latanoprost, compared to the control group.