46 eyes of 23 patients have been treated with topical Latanoprost 0.005 %. visual field was performed on all eyes. NFLT was measured using OCT. Radial peripapillary capillary (RPC) vascular density was measured using OCTA . mean ocular perfusion pressure (MOPP), and RPC vascular density were measured before and after treatment BY 2-3 MONTHS

All patients had bilateral primary open angle glaucoma diagnosed by increased IOP, visual field changes, and defective nerve fiber layer thickness (NFLT) on OCT examination.

All patients treated with topical Latanoprost 0.005% (XalatanTM, 2.5 ml eye drops, Pfizer) Inclusion criteria: age > 20 years, newly diagnosed patients with POAG. The exclusion criteria included optic nerve lesions other than glaucomatous changes, All patients completed their ophthalmic examination to detect BCVA, cycloplegic refraction, and anterior segment examination , IOP measuring by applanation tonometer, and indirect ophthalmoscope fundus examination.

Visual field testing. The thickness of NFL around the disc was evaluated using spectral domain optical coherence tomography (OCT) Optovue octa was used to quantify the density of the radial peripapillary capillary (RPC) vessels. This study employed software to quantify the capillary (microvasculature) density in both the entire image and in the peripapillary region specifically the superior, nasal, inferior, and temporal quadrants.

The mean arterial blood pressure (MAP) was determined by adding the diastolic blood pressure (DBP) to one third of the difference between systolic blood pressure and the diastolic blood pressure.

All eyes were treated with topical latanoprost 0.005% (XalatanTM, 2.5 ml eye drops, Pfizer) with dose of one drop at bedtime. IOP, MOPP, NFLT, and RPC vascular density were measured before the beginning of treatment and 1 and 3 months after treatment.

Inclusion Criteria:

POAG with no past ocular surgery or laser retinal treatment. No previous anti-glaucoma medications

Exclusion Criteria:

• optic nerve lesions other than glaucoma