Any other symptoms are attributable to the underlying process that caused the disc damage (such as pain with angle closure glaucoma). The main symptom of optic atrophy is vision loss. Because the optic nerve fiber layer is thinned or absent the disc margins appear sharp and the disc is pale, probably reflecting absence of small vessels in the disc head. This is the end stage of a process resulting in optic nerve damage. Optic atrophy is a sign and typically is noted as optic nerve pallor. A careful history with attention to past medical history including all medications, time course of vision loss, associated symptoms etc is critical for arriving at a correct diagnosis.Ī complete eye exam including visual field, assessing color and contrast vision, intraocular pressures, looking for afferent pupil defect, and fundoscopy should be done. History is critical in the diagnosis of optic atrophy since the physician needs to know how the eye arrived at this juncture. Quantification of the nerve fiber layer height and comparison with normative data can document axon loss and differentiate between optic nerve and retinal disease as a cause for vision loss. Optical Coherence Tomography has become a valuable tool to verify the status of the nerve fiber layer/ganglion axons. Damage from papilledema may leave retinal folds and sometimes glistening bodies in the optic nerve head. Severe optic atrophy with gliosis again in an elderly person could have been due to giant cell arteritis. Sector disc pallor in an older individual could have been caused by NAION. A complete diagnosis is based on optic nerve appearance, tests of visual function (visual field, contrast, color, acuity), identifying the causative factor of the damage, and ruling out other causes for vision loss (such as retinal causes).Ĭertain disc appearances can help to determine the cause for the optic nerve damage. Occasionally if the process causing damage is removed before apoptosis occurs (as for instance removal of a pituitary tumor compressing the chiasm or reducing inflammation in sarcoid) some improvement in visual function may be noted.
Damage to a part of the optic nerve results in loss of vision in the corresponding visual field. Severe damage may lead from legal blindness to no light perception. Subtle damage might not affect acuity but may lead to a loss of contrast or color vision. Since the optic nerve is the conduit for information from the retina to the brain, a damaged optic nerve will result in vision loss. Primary prevention (removal of the process causing the damage) is the goal to prevent loss of axons and optic atrophy (neuropathy). Medical practice is currently unable to return function (regrow axons) to an atrophic optic nerve, and at best is able to stabilize whatever function remains. Optic atrophy is the end stage of a process causing damage to the optic nerve. In optic nerve atrophy there is loss of axons and shrinkage of myelin leading to gliosis and widening of the optic cup. The optic nerve is myelinated by oligodendrocytes that do not regenerate after damage.
The optic nerve is a bundle of 1.2 million axons of retinal ganglion cells that carries visual information from the retina to the brain. Risk factors run the gamut from increased intraocular pressure (glaucoma), ischemia, compression (tumors), inflammation, infection, etc. Optic atrophy can occur due to damage within the eye (glaucoma, optic neuritis, papilledema, etc.), along the path of the optic nerve to the brain (tumor, neurodegenerative disorder, trauma, etc.), or it can be congenital (Leber’s hereditary optic atrophy, autosomal dominant optic atrophy). Optic atrophy is somewhat of a misnomer as atrophy implies disuse, and thus optic nerve damage is better termed optic neuropathy.Īnything that can compromise ganglion cell function can cause (over time) optic atrophy (and more broadly optic neuropathy).
Since the optic nerve transmits retinal information to the brain, optic atrophy is associated with vision loss. Optic atrophy is an end stage that arises from myriad causes of optic nerve damage anywhere along the path from the retina to the lateral geniculate.
Optic atrophy refers to the death of the retinal ganglion cell axons that comprise the optic nerve with the resulting picture of a pale optic nerve on fundoscopy.
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