CT of drusen bodies and other calcific lesions of the optic nerve: case report and differential diagnosis.

One of the major causes of misdiagnosis of papilledema is buried drusen of the optic nerve head [1, 2]. Optic nerve drusen are calcified concretions of unknown etiology, located within the optic nerve head just anterior to the lamina cribrosa. As these concretions enlarge they may become visible ophthalmoscopically. When buried in the nerve head, they may cause difficulties in the ophthalmoscopic differentiation from true papilledema. With the advent of highresolution computed tomographic (CT) scanning, appropriate axial and coronal cuts can demonstrate the calcified optic nerve head drusen and save the patient from further neuroradiologic procedures [2].