2259 A 20-year multicentre retrospective review of optic nerve sheath fenestration outcomes

ObjectiveTo determine the efficacy and safety of optic nerve sheath fenestration (ONSF) for idiopathic intracranial hypertension (IIH), and other indications from a major tertiary hospital and specialty eye referral hospital in Melbourne, Australia from July 2000 to December 2020.MethodAll patients undergoing optic nerve sheath fenestrations (ONSF) were retrospectively reviewed with patient demographics, surgery indications, visual acuity, visual fields, fundus photos of optic discs, retinal nerve fiber layers (RNFL), average thickness of optic discs on optical coherence tomography (OCT), treatments, and complications recorded. Non-parametric tests were used to compare the treatment groups pre- and post-operatively.ResultsA total of 127 eyes from 75 patients underwent ONSF, in which 92 eyes from 55 cases with IIH, 9 eyes from 5 cases with cerebral venous sinus thrombosis (CVST), and 26 eyes from 15 cases with other etiologies (Other). IIH cases post ONSF had a best corrected visual acuity (BCVA) improvement of 92% and ‘Other’ group BVCA of 80% at last follow up, both demonstrating a statistically significant improvement. All 8 CVST eyes demonstrated improvement of BCVA at last follow up. All groups demonstrated non-significant stabilisation/improvements in visual fields, OCT, and papilloedema grading. Common complications included transient diplopia (n=19, 15%) and worsening of visual function requiring further cerebrospinal fluid diversion procedures (n=10, 8%).ConclusionOur data supports the use of ONSF in the setting of raised intracranial pressure, papilloedema, and in visual failure not due to IIH or CVST and when other CSF diversion procedures or medical therapies have failed.