Validity of optical coherence tomography angiography in the differential diagnosis of papilledema and pseudopapilledema

PURPOSE: To assess the value of optical coherence tomography angiography (OCTA) peripapillary retinal vascularization in differentiating papilledema from pseudopapilledema. METHODS: A cross-sectional study, prospective recruitment patients diagnosed with papilledema and pseudopapilledema between January 2021 and December 2022. Papilledema: mild-moderate acute optic disc edema due to increased intracranial pressure. Pseudopapilledema: optic nerve drusen and other causes confirmed by multimodal imaging techniques. Mean and sectoral peripapillary flux index and perfusion density were measured using commercial software. Diagnostic performance was analyzed using the area under the receiver operating characteristic curve (AUC). RESULTS: Sixty-five patients (mean age, 36.5 years; 63.1% women) were included: 14 with papilledema (28 eyes; mean age 37.1 years, 9 women) and 51 with pseudopapilledema (95 eyes, mean age 36.4 years, 32 women), with no significant differences in age or gender. Significant differences were found for flux index in the nasal sector (p = 0.034). Mean perfusion density was significantly higher for papilledema (44.377%) than for pseudopapilledema (42.460%) (p = 0.036), as was perfusion in the nasal sector (p = 0.005). Mean vascular flux index had an AUC of 0.683 (95% CI, 0.518-0.848), with 76.9% sensitivity and 58.8% specificity, with a cut-off of 0.461. Mean perfusion had an AUC of 0.665 (95% CI 0.492-0.838), with 53.8% sensitivity and 76.5% specificity, with a cut-off of 44.25%. CONCLUSIONS: OCTA displayed higher peripapillary flux index and perfusion in papilledema than pseudopapilledema in the nasal region. These parameters showed moderate diagnostic accuracy and may serve as adjunctive tools in the differential diagnosis of optic disc swelling.