Study Status: Completed
Recruit Status: Completed
Study Type: Observational
Official Title: Pathological Cerebral Venous Drainage System Giving Large Pressure Difference Between Brain and Eye at Upright Posture: a Possible Cause to Normal Tension Glaucoma.
Brief Summary: The main aim of this study is to determine the trans-laminal cribrosa pressure difference (TLCPD) for normal tension glaucoma (NTG) patients from the brain and the eye in supine, upright and minor head down tilt positions. It is also to investigate the venous drainage system in the same body positions.