Fig. 1From: Peripapillary retinal artery in first diagnosed and untreated normal tension glaucomaFundus photograph showing method of measurement of peripapillary retinal arteriolar calibers (PRACs). We plotted superior temporal, inferior temporal, superior nasal, and inferior nasal retinal arteries (black arrows), and then measured their calibers at the optic disc border (yellow line) using Image J softwareBack to article page