Inclusion Criteria:  Age of 30 years or older for both control and glaucoma groups. Spherical equivalent (SE) between -2 and +2 D. No history of previous eye surgery, trauma, or systemic diseases.  Exclusion Criteria:  Spherical equivalent greater than +/- 2.00 diopters (D). Media opacity as (cataract or corneal scar). Any history of ocular surgeries or trauma. Optic nerve anomaly or other retinal diseases. Unreliable visual field tests (33% fixation losses, false positive, and false- negative results).