Carotid artery dissection following dental extraction revealed by ischaemic optic neuropathy

To describe a case of posterior ischemic optic neuropathy (PION) revealing carotid arterial dissection occurring after ipsilateral tooth extraction.

A 56-year-old patient referred for sudden loss of vision of the left eye (LE) since 3 weeks. Initial visual acuity was 10/10 in the right eye (RE) and limited to light perception in the LE. Ophthalmological examination was without abnormalities in the RE. A relative afferent pupillary defect was noted in the LE. Fundus examination of the LE revealed a papillary pallor, without excavation. Fluorescein angiography revealed no abnormalities in both eyes, including normal choroidal filling. The diagnosis of left PION was retained. A careful questioning of the patient revealed the history of tooth extraction under intra-oral local anesthesia one day before the vision loss. Investigational work up revealed a dissection of the left internal carotid artery.

Dissection of the internal carotid artery is a rare but possible cause of PION. Ocular involvement may be the only manifestation. Clinicians should be aware of such manifestation especially in case of particular context of micro-trauma, such as dental procedures, and look for an underlying cause that may be potentially fatal.