An interpretation of optic nerve tortuosity. A case report.

Magnetic resonance imaging disclosed both optic nerve tortuosity and kinking in a 64-year-old man with orbital pain and monolateral abducens nerve palsy. The association between optic nerve tortuosity and abducens nerve palsy is often described in literature reports of idiopathic intracranial hypertension. However the diagnosis of idiopathic intracranial hypertension was excluded in our patient because of the absence of other signs such as papilledema (universally present in the cases of idiopathic intracranial hypertension), visual loss, headache and flattening of the posterior sclera. Other possible diagnoses to be considered when looking at a case of optic nerve tortuosity are neurofibromatosis and/or optic nerve glioma. Tortuosity of both optic nerves seems to be isolated in our patient and not associated with other diseases or disorders. We suggest that in some patients optic nerve tortuosity could be correlated with an aberrant anatomical development of the optic nerve. Further studies are necessary to confirm this hypothesis which currently remains conjectural.