Abnormalities of Vision

(A).Decreased visual acuity

1.Near: (hyperopia/long sighted,persbyopia,astigmatism)

2.Distance: (myopia/short sighted,astigmatism)

(B).Abnormal of color vision

1.Hereditary: bilateral

2.Acquired: often unilateral

(C).Abnormal visual field

1.Unilateral defects in retinal and optic nerve diseases

2.Bilateral defects in diseases at or posterior to chiasma

(D).Defective dark adaptation

(E).Iridescent vision ( 'halos')

(F).Floaters

(G).Photopsia

1.Unilateral: retinal stimulus other than light

2.Bilateral: visual hallucination

a.Unformed: occipital lobe origin

b.Formed: temporal lobe origin

(H).Micropsia (objects appear smaller)

1.Fovea centralis abnormality

(I).Macropsia (objects appear larger)

1.Fovea centralis abnormality

(J).Cortical blindness: bilateral lesions of occipital cortex

(K).Perceptual blindness: lesions of angular gyrus of parieto-occipital fissure

(L).Diplopia (double vision)

1.Physiologic

2.Monocular: local disturbance of one eye

3.Near only: convergence abnormality

4.Distance only: divergence abnormality

5.Varies with eye or head movements: ocular muscle weakness