Optic Nerve Head Drusen

Contact B-scan ultrasonography can be of great help in diagnosing buried drusen (arrow) of the optic nerve head. When drusen are buried deep in the nerve and invisible to white light, ultrasound has proved to be diagnostically helpful. Drusen of the nerve head are excellent reflectors of sound (probably due to the presence of calcification). Drusen themselves have an extensive shadowing effect, but since we are already shooting through the optic nerve shadow, much of this effect is not evident. They stand out like small pebbles on the head of the optic nerve and their characteristic hyper-reflective signal persist at the lowest decibel levels of gain.

Also in this eye, scattered vitreous opacities of very low reflectivity are visible, which may be related to advancing age. In younger eyes, the clear vitreous body generally produces no echoes.