How to Diagnose Hemianopsia

Hemianopsia is a loss of half the vision in both eyes. It indicates damage in the posterior part of the brain that is responsible for vision and frequently results from a stroke or traumatic brain injury.

Instructions

• 1

  Identify the type of hemianopsia. Binasal hemianopsia is blindness of the inner half of the eyes, bitemporal hemianopsia is blindness of the outer half of the eyes and homonymous hemianopsia is blindness of the same visual field in both eyes.

• 2

  Gather the patient history. Because hemianopsia is a problem with the brain and not the eyes, patients may not directly notice the blindness. Instead, they may report running into objects, tripping or falling.

• 3

  Inquire about reading difficulties. Patients with hemianopsia frequently lose their place while reading, especially when it is on the right side. A right homonymous hemianopsia will cause the patient to miss the end of a line or long word. Patients with a left homonymous hemianopsia will tend to have difficulty moving from the end of a line to the beginning of the next line.

• 4

  Check for psychological signs of hemianopsia; the patient may be startled by objects entering the functioning part of their visual field. Patients can become extremely fearful of traveling or shopping and may even experience panic attacks in a crowded store.

• 5

  Confirm a diagnosis of hemianopsia with vision tests. Standard eye charts and color vision charts are helpful in determining the visual field that is affected. Use special charts that do not require the ability to read or verbalize for illiterate or mentally retarded patients. These may include Allen figures, HOTV charts, a Sheridan Gardner chart or Landolt C charts.