Optic Nerve Sheath Fenestration for Progressive Visual Loss in Cerebral Venous Sinus Thrombosis: A Long-Term Retrospective Observational Study

Abstract

Introduction: Progressive cerebral venous sinus thrombosis (CVST)-induced visual loss remains problematic, despite decreasing overall mortality owing to early diagnosis and aggressive treatment. Optic nerve sheath fenestration (ONSF) improves or stabilizes visual function in patients with idiopathic intracranial hypertension; however, its role in CVST awaits elucidation. We evaluated the efficacy and safety of ONSF in resolving CVST-induced visual impairment based on long-term observation. Methods: This observational study included 18 patients with progressive CVST-induced visual loss, who had undergone ONSF between 2012 and 2021. Patients received maximum medical therapy, including anticoagulants and intracranial pressure (ICP)-lowering medications. The best-corrected visual acuity (BCVA), visual fields (VFs), and optic nerve head were assessed at baseline, at 1 week after ONSF, and over 6 months after ONSF. Activities of daily

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

“…With only two eyes in the 'other' cohort experiencing transient diplopia as the predominant complication (Table 2), ONSF can be considered a safe treatment for other conditions. 12 The automated visual field perimetry MD scores demonstrated improvement on comparison between the pre-operative and >360 day values in both the overall and IIH subgroup (Figure 2). The improvements noted in our series (improvement in 13.8% of eyes; stability in 17.2%) is lower than the reported 65.2% improvement noted in a recent review.…”

“…ONSF performed in the appropriate setting is a recognised treatment to preserve visual function in IIH and CVST. 12 , 13 However, little is known about the outcomes of ONSF used for other disease processes, and the natural history over time following the procedure. 13 This retrospective analysis aimed to elucidate the natural history of outcomes following ONSF over various time intervals, as well as providing insights into indications other than IIH and CVST.…”

“…With only two eyes in the ‘other’ cohort experiencing transient diplopia as the predominant complication ( Table 2 ), ONSF can be considered a safe treatment for other conditions. 12 …”

“…A similar improvement was noted in the CVST and other subgroups, indicating a similar effect in these cohorts, which has been demonstrated in prior observational studies in CVST patients. 12 The rapid lowering of peripapillary RNFL measurements post-ONSF is objective evidence of successful surgery through local release of pressure and reduction of ICP. This is also supported by prior studies demonstrating that OCT can also be used to non-invasively measure ICP in IIH.…”

“…11 Recent observational data demonstrated efficacy in the use of ONSF in cerebral venous sinus thrombosis (CVST) with stability/ improvement achieved in 80% of eyes. 12 Case literature reports of ONSF as an intervention in multiple secondary processes associated with raised ICP includes central nervous system masses, optic nerve sheath meningoceles, postoperative subarachnoid haemorrhage of the optic nerve, acute retinal necrosis syndrome, non-arteritic ischaemic optic neuropathy, and central retinal vein occlusion. [13][14][15] In this retrospective analysis, we aimed to report the longitudinal outcomes of ONSF for patients with IIH, CVST, and other aetiologies with regard to visual function.…”