All subjects recruited from the Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Clinical ophthalmic assessments including measurement of visual acuities, intraocular pressure, slit-lamp microscopes and funduscopes examinations, cup-to-dick ratio (CDR) evaluation, visual field test [Octopus 101 Automated Perimeter, Haag-streit, Switzerland. Program G2], optical coherence tomography for retinal nerve fiber layer thickness(RNFLT) around the optic disk[Stratus OCT，Carl Zeiss Meditec, Dublin, CA .Scan Type :Fast RNFLT 3.4, Scan Length: 10.87mm].