Ocularultrasound versus SD-OCT in early papilledema differentiation

Differentiating early papilledema from pseudopapilledema remains a considerable diagnostic challenge in neuro-ophthalmology due the risks surrounding unnecessary neuroimaging or under-treatment of elevated ICP. Therefore, it is of interest to study of ocular ultrasonography and SD-OCT was carried out in 60 patients with elevation of the optic disc from September 2022 to February 2024. Papilledema was defined as optic nerve sheath diameter >3.3 mm, a positive 30°C test and crescent sign while pseudopapilledema was often associated with hidden disc drusen. SD-OCT had higher sensitivity than ultrasonographic examination (86.7% vs 81.7%) and eyes with papilledema showed thicker peripapillary RNFL, increased ONH volume, decreased GCIPL, enlargement of the blind spot or reduced contrast sensitivity and colour desaturation. The two modalities complement each other - SD-OCT provides quantification and allows differentiation whereas ultrasonography can show anatomical biomarkers, together allowing the early detection of intracranial hypertension as well as avoiding invasive investigations in cases of pseudopapilledema.