Ocular Ultrasonography may not Distinguish Papilledema From Pseudopapilledema: Study

A group of researchers from U.S.A conducted a study to prospectively evaluated the sensitivity and specificity of ocular ultrasonography (OUS) to distinguish papilledema from pseudopapilledema.

Forty-nine study participants, with optic disc elevation, underwent neuro-ophthalmic evaluation, Ocular Ultrasonography (OUS), fundus photography, and optical coherence tomography (OCT) of the optic nerve head at the initial and follow-up visits (≤6 months apart). Participants were classified as having papilledema if there was a change in optic nerve appearance on fundus photographs, as determined by a masked observer, between initial and follow-up visits ≤6 months apart. Ocular Ultrasonography (OUS) was considered positive when the optic nerve sheath width was >3.3 mm and the 30° test was positive. Ocular ultrasonographic findings were correlated in patients who had papilledema vs patients who had pseudopapilledema. In a subanalysis, OUS findings were also correlated with change in peripapillary retinal nerve fiber layer thickness on optical coherence tomography (OCT) of the optic nerve head between initial and follow-up visits.

The results of the study are as follows:

· Ocular Ultrasonography (OUS) was 68% (17/25) sensitive for papilledema and 54% (13/24) specific for pseudopapilledema.

· When using OCT parameters to define papilledema, the sensitivity of Ocular Ultrasonography (OUS) to diagnose papilledema decreased to 62%.

· Positive Ocular Ultrasonography (OUS) correlated with elevated opening pressure on lumbar puncture and with signs of increased intracranial pressure on MRI.

Thus, the researchers concluded that Ocular Ultrasonography (OUS) alone was less sensitive in diagnosing papilledema than previously thought. Therefore, Ocular Ultrasonography (OUS) may not be helpful in distinguishing between papilledema and pseudopapilledema.

Reference:

A study titled, "Role of Ocular Ultrasonography to Distinguish Papilledema From Pseudopapilledema" by Kolhi A et. al published in the Journal of Neuro-Ophthalmology.

doi: 10.1097/WNO.0000000000000984