Abnormal optic nerve morphology Optic nerve sheath dilatation 2025-08-10T11:09:56Z An abnormal increase in the diameter of the optic nerve sheath, typically due to elevated intracranial pressure or local pathology affecting cerebrospinal fluid (CSF) dynamics. It can be detected via imaging modalities such as ultrasound or MRI and may be associated with papilledema, idiopathic intracranial hypertension, or optic nerve tumors. Enlarged optic nerve sheath Optic nerve sheath expansion Dilation of the optic nerve sheath