Sudden Loss of Vision (Bilateral)

Partial loss of vision

An occipital CVA will infarct the visual cortex on one side, resulting in a homonymous hemianopia of the contralateral side to the lesion.

Often the macula is spared, leaving the visual acuity intact.

If just a portion of the visual cortex is lost, the patient may only lose one corresponding quadrant of vision in each eye – a homonymous quadrantinopia.

Sudden blurring of vision

The degree of visual loss associated with the above conditions may vary, depending on the degree of the pathology. For example, a patient with a mild case of central retinal vein occlusion may have vision of 6/12, while another patient's vision may be reduced to hand motions.

Total loss of vision

In order suddenly to lose all vision in both eyes the patient would have to sustain a cerebrovascular occlusive event compromising both occipital lobes (visual cortices), optic tracts or radiations simultaneously.

The patient may have previously lost vision in one eye but only noticed it when they lost the vision in their good eye. They become concerned, check their vision in both eyes and notice that vision is poor bilaterally.

Very rarely patients will have retinal pathology affecting both eyes in rapid succession (may occur in untreated GCA).

Occasionally malingerers present claiming to have complete vision loss: watch how they walk and act. If the patient is completely blind he or she will not fixate on you and will struggle to negotiate obstacles.