Students Who Are Blind or Have Low Vision

Visual impairment

means an impairment in vision that, even with correction, adversely affects a child’s educational performance.

low vision

more commonly used term is “

blindness

• any person whose central visual acuity does not exceed 20/200 in the better eye with corrective lenses or a visually impaired person whose vision with best correction is 20/60 in the better eye, or with a field restriction of 105 degrees if monocular vision; 140 degrees if binocular vision

Myopia

(i.e., nearsightedness) makes faraway objects look blurry.

Hyperopia

(i.e., farsightedness) makes nearby objects look blurry.

Astigmatism

can make faraway and nearby objects look blurry or distorted.

Refractive errors

are a type of vision problem that makes it hard to see clearly. it happen when the shape of the eye keeps light from focusing correctly on the retina.

Ocular Motility Disturbance

any abnormal eye alignment or difficulty controlling eye movements. These conditions involve the brain and the muscles that control eye movement

Strabismus

is a condition where the eyes are not facing in the same direction.

Amblyopia

is a condition in which the brain fails to process the information from one eye.

Nystagmus

is characterized by fast, uncontrollable eye movements.

retinopathy of prematurity (ROP).

• is an eye disease that may occur in babies who are premature or who weigh less than 3 pounds at birth. it happens when abnormal blood vessels grow in the retina.

retinitis pigmentosa (RP)

• a group of rare eye diseases that affect the retina, causes cells in the retina to break down slowly over time, causing vision loss.

Cortical visual impairment (CVI)

• is a disorder caused by damage to the parts of the brain that process vision.

• vision problems caused by their brain that cannot be explained by a problem with their eyes