Cup-to-disc ratio in idiopathic intracranial hypertension without papilloedema

This study seeks to characterise potential differences in the cup-to-disc ratio (CDR) of patients with idiopathic intracranial hypertension (IIH) with papilloedema (IIHWP) compared with IIH without papilloedema (IIHWOP). The medical charts, optical coherence tomography (OCT), and digital optic disc photos of 30 patients (59 eyes) with IIHWP and 4 patients (8 eyes) with IIHWOP were reviewed retrospectively. The CDR values of the two groups were analysed using the Wilcoxon-Mann-Whitney test. Results showed a statistically significant smaller CDR in patients with IIHWP as compared with IIHWOP. These findings suggest that structural factors of the optic disc may play a role in the development of or lack thereof of papilloedema in patients with IIH.