A student with a visual impairment is one whose vision, even with correction, adversely impacts a child's educational performance. Examples are children whose visual impairments may result from congenital (from time of birth) defects, aquired defects, eye diseases, or injuries to the eye. Learn more about IDEA guidelines related to vision.
A student with a visual impairment is one whose vision, even with correction, adversely impacts a child's educational performance. The term "Visual Impairment" is an umbrella term that includes both low vision and blindness.
1. Blind refers to a child whose visual acuity is 20/200 or less in the better eye after correction or who has a limitation in the field of vision that subtends an angle of 20 degrees. There are different degrees of blindness and some children who are legally blind have useful vision and may still read print.
2. Low Vision refers to a child whose visual acuity is better than 20/200 in the better eye after correction OR who has a limitation in the field of vision that adversely impacts educational progress.
*Progressive visual disorders: Children, whose current visual acuity is not adversely impacting their educational progress, but who have a medically indicated expectation of visual deterioration may also be considered for vision impaired eligibility based on documentation of the visual deterioration from the child's optometrist or ophthalmologist. This way, the Teacher of Students with Visual Impairments can provide instruction and support to prepare the student for the impending vision loss.
**Students who appear to be more visually impaired than one would suspect on the basis of their eye exam or students whose visual ability appear to be highly variable for no apparent reason may be suffering from damage to the visual pathway or visual cortex. When cerebral/cortical visual impairment or post trauma vision syndrome is suspected, there are several ways to detect damage to the visual cortex or visual pathway:
1. Visually Evoked Potential Mapping (VEP Map) detects the processing of visual stimuli by the visual cortex.
2. Computerized tomography (CT) scan and magnetic resonance imaging (MRI) indicate areas of destroyed brain structure.
3. Electroencephalogram (EEG) measures the electrical activity of the brain.