A rare morphological variant: Bilateral accessory optic canal.

The optic canal (OC) transmits the optic nerve (ON) and ophthalmic artery (OA) from the skull base to the orbit. Its morphological variability is narrow, and most commonly its dimensions are being studied. We observed an unexpected variant during a routine investigation of our osteological collection. The right and left OCs were carefully inspected. Both presented with an accessory canal inferolateral to the main OC. The dimensions were 1.88×1.96mm (left side) and 2.41×2.89mm (right side). The rest of the orbital anatomy was free of variants. Most probably, the content of the bilateral accessory canals corresponds to the ophthalmic artery. The OC duplication is considered rare, while the bilateral appearance is a scarce variant; however, surgeons operating the orbit should keep this in mind and check for such variations preoperatively.