Tomographic evaluation of the retinal pigment epithelium angle in papilledema due to idiopathic intracranial hypertension: A case series

Aim and Background: Idiopathic intracranial hypertension (IIH) causes elevated intracranial pressure (ICP) and papilledema. This study evaluated changes in the retinal pigment epithelium (RPE) angle on optical coherence tomography (OCT) before and after treatment and their relationship with ICP. Methods: This retrospective case series included eight patients with IIH and papilledema. ICP was measured by lumbar puncture before and after treatment. Spectral-domain OCT was used to quantify the RPE angle in both eyes on radial B-scans through the optic nerve head. All analyses were performed in Stata v14, including descriptive statistics, paired comparisons, and linear correlation between ΔICP and ΔRPE. Results: Eight patients (75% female; mean age 37.0 ± 18.6 years) were included in the study. Mean ICP decreased from 40.0 ± 16.2 to 21.6 ± 6.0 mmHg after treatment (ΔICP = −18.4 ± 15.0 mmHg; P < 0.01). RPE angles showed modest, nonsignificant reductions in both eyes (OD: −3.25° ± 5.52°; OS: −1.0° ± 2.78°). No correlation was observed between ΔICP and ΔRPE, and Bland–Altman analysis demonstrated good interocular agreement with minimal bias. Conclusion: Although ICP normalized after treatment, changes in the RPE angle were small and variable, suggesting that peripapillary structural recovery may lag behind ICP reduction. Larger studies are needed to clarify the role of RPE angulation as a complementary OCT marker in monitoring IIH.