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Optic Nerve Atrophy Parts of the visual system affected Optic Nerve Atrophy may be congenital or adventitious. If congenital, it is usually hereditary. The milder form is autosomal dominant and has a gradual onset of deterioration in childhood but little progression thereafter; the more severe form is autosomal recessive and is present at birth or within 2 years; this form is accompanied by nystagmus (rapid “to” and “fro” movements of the eyes). The optic nerve carries images of what we see from the eye to the brain. Comprehensive description Optic nerve atrophy is tissue death of the nerve that carries the information regarding sight from the eye to the brain. There are many unrelated causes of optic atrophy. The most common cause is poor blood flow, called ischemic optic neuropathy, which most often affects the elderly. Effects of the condition on the visual system Optic nerve atrophy, death of nerve cells within the optic nerve, affects the optic nerve’s ability to convey nerve signals from the eye to the brain. Optic nerve atrophy can be partial or complete; when complete there is total loss of vision. conditions of the eye or systemic neurologic disorders can cause optic nerve atrophy. Symptoms include diminished visual acuity and visual field. Common treatments Damage from optic nerve atrophy cannot be reversed. The underlying disease must be found and treated, if possible, to prevent further loss. Rarely, conditions that lead to optic atrophy may be treatable. ONA cannot be corrected with glasses. Anticipated functional implications of the condition Visual and Behavioral Characteristics The optic nerve can also be damaged by shock, various toxic substances, radiation, and trauma. Various eye diseases, most commonly glaucoma, can also cause optic nerve atrophy. In addition, the condition can be caused by diseases of the brain and central nervous system, such as cranial arteritis (sometimes called temporal arteritis), multiple sclerosis, brain tumor, and stroke. There are also several rare forms of hereditary optic nerve atrophy that affect children and young adults. Symptoms Blurred vision Abnormal side vision Abnormal color vision Poor constriction of the pupil in light Decreased brightness in one eye relative to the other Visual acuity may range from nearly normal to totally blind. Children with bilateral central blind spots (scotomas) may "overlook" in order to see a person or object. Children may have difficulty identifying colors based on their individual color vision defect. Enhancing visual function may require high levels of illumination and enlarged print with high contrast; magnification may be useful in some cases. Color perception may be impaired. Ongoing evaluation and communication among family, medical and education specialists is essential to develop the best home and school program for the child with ONA. Assessment and services from a pediatric ophthalmologist, a teacher of the visually impaired, and a specialist in Orientation and Mobility who keep in close communication with caregivers will ensure maximum development for the child. Carefully observe a young child with ONA to gather valuable information about the way he/she sees best. Determine the best position for the child and her toys to accommodate for central field loss. The physical demands of looking at an object or toy for a long period of time may cause eye fatigue. Allow a child with ONA to rest between activities requiring vision. Use touch and spoken description to tell a child about present and future activities. The use of additional senses is necessary to enrich the learning process. Good contrast and lighting are essential for the child with ONA to see objects in the environment clearly. For example, offering dark colored food on a light plate, or a light toy against a dark background provides good contrast. Using bold colors (red, yellow, green, blue) and simple, clear pictures will help the child to see more clearly. Use familiar and real objects to encourage visual attention. Change one characteristic of a familiar object only after the child is able to recognize it consistently. For instance, after the child is able to recognize a cup that is blue consistently, change the cup to red. When introducing unfamiliar objects to the child, relate them to familiar objects and settings. Note: If a child with ONA also has Cortical Visual Impairment (CVI), strategies effective with the CVI population should be used. References: University of Maryland Medical Center. (Copyright 2011). Retrieved from http://www.umm.edu/ency/article/0016 22.htm Beltina.org. (n.d.). Retrieved from http://www.beltina.org/healthdictionary/optic-nerve-atrophy-causesdiagnosis-treatment.html Texas School for the Blind and Visually Impaired. (2005, October 31). Retrieved from http://www.tsbvi.edu/seehear/spring99/ ona.htm The Special Education Exchange. (Copyright 1996-2011). Retrieved from http://www.spedex.com/resource/docu ments/veb/optic_atrophy.html University of Michigan Kellogg Eye Center. (Copyright 2010). Retrieved from http://www.kellogg.umich.edu/patientca re/conditions/optic.atrophy.html Developed by Jerry Mullins