Association of papilledema severity with retinal vessel tortuosity in idiopathic intracranial hypertension

PURPOSE: Idiopathic intracranial hypertension (IIH) induces papilledema and can result in progressive visual dysfunction and retinal vascular changes. The purpose of the current study was to determine cross-sectional and longitudinal associations between papilledema severity and retinal vessel tortuosity (RVT) in IIH. METHODS: Images from 24 eyes of 15 patients diagnosed with papilledema were acquired at two visits. Papilledema severity was graded by Frisen score (FS). Images were analyzed to determine RVT in arteries and veins within the peripapillary region using the first-order derivative method. Inter-visit differences in FS (ΔFS) and RVT (ΔRVT) were calculated. Generalized estimating equation models determined associations of FS and ΔFS with RVT and ΔRVT, respectively. RESULTS: Based on compiled arterial or venous RVT data from both visits, there was no significant association between RVT and FS (p = 0.89), whereas venous RVT (0.31 ± 0.02; N = 48) was significantly higher than arterial RVT (0.24 ± 0.01; N = 48) (p = 0.03). Compared to the ΔFS = 0 group, venous ΔRVT was higher in the ΔFS = 3 group (β = 0.05, p = 0.005), while arterial ΔRVT was higher in ΔFS ≥ 1 (β ≥ 0.04; p ≤ 0.04). CONCLUSION: The finding of an association between improvement in papilledema and reduction in RVT shows promise for vessel tortuosity as a biomarker for monitoring disease progression and response to therapeutic interventions, as well as advancing knowledge of retinal vascular changes due to papilledema.