Optic disc drusen demonstrate a hyperechogenic artifact in B mode ultrasound

We describe a new, specific, hyperechogenic artifact spot in B-mode ultrasound (US) in patients diagnosed with optic nerve drusen (OND). This is a retrospective chart review of 34 consecutive patients with OND using B-scan US. The patients underwent full ophthalmic evaluation and neuro-ophthalmic examination. In all cases, a typical hyperechogenic spot was seen within the acoustic shadows on medium or high gain settings. The length between the US probe and the OND, and the distance between the OND and the artifact were recorded for each patient. In all cases, a typical hyperechogenic spot was seen within the acoustic shadows on medium or high gain settings. Sonograms showed a hyperechogenic focus in all eyes. The average ratio between the cornea-OND distance (25.5mm) and the OND-hyperechogenic spot (32.1mm) distance was 1.26. The size of the hyperechogenic spot was proportional to the size of the deposit on the disc, with the most marked attenuation of the beam seen in the largest lesions. B-scan US is a very sensitive and reliable detector of both superficial and buried OND. The described hyperechogenic artifact spot may be an additional mode to support diagnosis of OND. This finding might be helpful for making a differential diagnosis between OND and papilledema.