Abstract: In recent years, it has been proposed that the impairment of cerebrospinal fluid (CSF)dynamics is the common pathophysiological mechanism causing diseases associated with optic nerve impairment. Further study of CSF dynamics, especially optic nerve subarachnoid space (ONSAS) cerebrospinal fluid dynamics, may contribute to the understanding of conditions such as idiopathic intracranial hypertension, spaceflight-associated neuro-ophthalmic syndrome, normal-tension glaucoma and other diseases that cause optic nerve damage and visual impairment, and provide more ideas for their prevention and treatment.The CSF may not flow into ONSAS because of the degree of optic canal stenosis, intraocular pressure and the variation of anatomic structure. The change of ONSAS cerebrospinal fluid pressure is the main factor that cause optic disc edema and atrophy. The changes of pressure and inflammation stimulate the proliferation of meningeal epithelial cells in ONSAS and make the space of lumen become smaller, it leads to the occurrence of optic nerve sheath compartment syndrome, which damages the CSF dynamics and further leads to optic nerve injury. At present, there is no gold standard for evaluating CSF pressure in ONSAS and means to monitor CSF dynamics in real time. The change of CSF pressure in ONSAS can only be roughly judged by the change of optic nerve sheath diameter or intracranial pressure.

Key words: cerebrospinal fluid dynamics, optic nerve subarachnoid space cerebrospinal fluid pressure, optic nerve sheath, optic nerve damage