RT Journal Article SR Electronic T1 Cerebrospinal fluid segregation optic neuropathy: an experimental model and a hypothesis JF British Journal of Ophthalmology JO Br J Ophthalmol FD BMJ Publishing Group Ltd. SP 1088 OP 1093 DO 10.1136/bjo.2009.171660 VO 94 IS 8 A1 Gregor P Jaggi A1 Mickey Harlev A1 Urs Ziegler A1 Shlomo Dotan A1 Neil R Miller A1 Hanspeter E Killer YR 2010 UL http://bjo.bmj.com/content/94/8/1088.abstract AB Aim To describe the histological changes in the optic nerve (ON) after experimental segregation of cerebrospinal fluid (CSF).Methods In seven sheep, a silicone band was placed around one ON to compress the subarachnoid space (SAS) surrounding the nerve, thus blocking the flow of CSF without compressing the ON itself. After 4 or 21 days, both the ligated and untouched ONs were removed and evaluated histologically.Results All treated ONs showed marked loss of axons, destruction of myelin and swelling of meningoepithelial cells, most pronounced in the proximal ON adjacent to the globe at the location most distant to the ligature. There was no significant difference in histological findings between the ONs that were ligated for 4 days and those with 21 days of ligature.Conclusion CSF segregation in the ON by blocking the SAS leads within 4 days to severe nerve damage. The increasing severity of these changes with increasing distance from the site of the ligature argues against simple pressure- or microperfusion-dependent effects and supports the hypothesis that interruption of CSF flow in the SAS of the ON can produce damage due to a change of CSF flow and content.