The role of cerebrospinal fluid pressure (CSFp) in glaucomatous optic neuropathy was initially raised 30-40 years ago. This concept has garnered more interest recently due to new findings in this area. Patients who underwent lumbar puncture (LP) and had POAG were found to have lower CSFp compared to controls in a chart review. Further studies demonstrated a positive correlation between optic nerve damage and the translaminar pressure gradient (TPG), calculated as the CSFp subtracted from the IOP. In 2010, a Chinese group suggested that normal-tension glaucoma (NTG) patients have significantly lower CSFp compared to POAG, and that TPG is greater in NTG and POAG patients compared to controls. The same group also showed that OHTN patients have higher CSFp than POAG patients, suggesting a protective effect of high CSFp when IOP is elevated. Thus, a role for CSFp in the pathophysiology of glaucoma may exist.