Impaired function of the optic nerve due to damage or disease. The many causes include: glaucoma, inflammation (eg optic neuritis related to multiple sclerosis), ischaemic (eg post anterior optic neuropathy), compression (eg from masses in the orbit or thyroid eye disease), trauma, toxic from poor nutrition or drug treatment, post infective and occasionally hereditary.
Clinical Features
Impaired visual acuity
Impaired peripheral vision
Impaired colour vision
Visible changes may be present in the optic nerve as it leaves the eye, often initially swollen, later pale (optic atrophy); characteristic excavated appearance in glaucoma (cupping)
