Extent of transverse sinus stenosis does not predict visual outcomes in idiopathic intracranial hypertension.

Abstract

We aimed to investigate whether the degree of transverse sinus stenosis (TSS) on magnetic resonance venography (MRV) can predict visual outcomes in patients with idiopathic intracranial hypertension (IIH). A chart review identified IIH patients followed for at least 6 months. Mean deviation (MD) on visual field (VF) testing at initial and last follow-up visits, best corrected visual acuity (BCVA), patients' age, body mass index, and lumbar puncture opening pressure were recorded. MRV was used to grade TSS on a scale of 0-8 using the grading scheme proposed by Farb et al., whereby a lower score indicates a greater degree of stenosis. Linear regression analysis was used to test for association between above variables and MD on VF, including change in MD over time. 44 female patients were followed for a median of 26 months. All patients had unilateral or bilateral TSS on MRV. The median TSS score was 3/8. The median BCVA was 0.06 logMAR at baseline. The median VF MD was -3.02 dB at baseline and -1.96 dB at final follow-up. There was no significant association between the degree of TSS and either baseline MD (P-value = 0.34) or the change in MD on VF over the course of follow-up (P-value = 0.54). Baseline BCVA (P = 0.045) and baseline MD (P < 0.001) were the only significant predictors of changes in MD on VF over follow-up. Baseline BCVA and MD on VF were the only significant predictors of visual outcome in IIH patients. While all patients demonstrated TSS on MRV, the degree of TSS did not correlate with visual prognosis.