Optical coherence tomography angiography in nonarteritic anterior ischemic optic neuropathy due to optic nerve head drusen.

Optic nerve head drusen (ONHD) are typically benign hyaline and calcified concretions located within the optic nerve. Initially asymptomatic, they can increase slowly in size and number over time, and they can cause mechanical stress at the axons of the optic nerve and progressively lead to a loss of the visual field and papillary vascular changes. Here, we reported a rare case of a young patient with bilateral ONHD complicated by a nonarteritic anterior ischemic optic neuropathy (NAION) in the right eye. The aim of this case was to evaluate, using optical coherence tomography angiography (OCTA), the vascular network of the papillary region in both eyes in the presence of this ischemic event associated to ONHD. At OCTA examination, the whole papillary region revealed a general rarefaction of the vascular network, but it turned out to be greater in the right eye affected by nonarteritic anterior ischemic optic neuropathy than in fellow eye. Therefore, these findings demonstrated that ONHD may determine significant ischemic events of the optic nerve and OCTA represents a valid and noninvasive tool in the diagnosis and in the pathogenesis of these rare cases of NAION associated to ONHD in young patients.