Visual Field

Question 1

Hemianopsia | Hemanopia

Answer 1

Visual Field Loss in 1/2 the field of one eye.

Question 2

Intracranial Space-Occupying Lesions

Answer 2

Tumours or abscesses present within the Cranium or Skull. These lesions put pressure on the adjacent brain tissue causing its damage.

Question 3

Perimetry

Answer 3

The systematic measurement of Visual Field Function.

Question 4

What are the 2 types of Perimetry?

Answer 4

1. Goldmann Kinetic Perimetry

2. Threshold Static Automated Perimetry

Question 5

What is a Visual Field Test?

Answer 5

Detect dysfunction in central and peripheral vision which may be caused by various medical conditions such as glaucoma, stroke, pituitary disease, brain tumours or other neurological deficits.

Question 6

Confrontation Visual Fields

Answer 6

Detecting and monitoring GROSS field defects.

Question 7

Confrontation Stick:

Answer 7

• 5mm white bead on black stick (for use if dark walls in room)
• 15mm red bead on white stick (for use if light walls in rooms)

Stick ~ 30cm long, 3mm diameter

Question 8

Procedure for Confrontation Test -

Answer 8

1. Room lights on
2. Prescription NOT worn
3. Hold up the target and explain:
   “I am going to estimate your field of view with this target.”
4. Ask:
   “Please cover your LE with the palm of your hand.”
5. Occlude your RE with the palm of your hand
6. Point at your LE and ask:
   “Please look at the middle of my lower eyelid.”
7. Explain
   “I will move the target inwards from outside the field of view. Please tell me when you first see the target. I will then continue to move the target into the centre and I want you to tell me if it disappears or fades at any point.”
8. Hold target equidistant between you and patient
9. Move target slowly inwards in all radial meridians.
10. You must fixate patient’s RE and check their fixation.
11. Compare their field to yours
12. Patients blind spot should cause the target to disappear at a point in the temporal visual field.
13. Repeat for patients LE

Question 9

Threshold

Answer 9

Intensity of the stimulus seen 50% of the time at a location.

Question 10

Suprathreshold Algorithm test ______

Answer 10

At a set intensity greater than threshold

Question 11

Negative Scotoma

Answer 11

A scotoma that is not ordinarily perceived, but is detected only on examination of the visual field.

Question 12

Scintillating Scotoma

Answer 12

A blind spot in the visual field that is bordered by shimmering or flashing light and that is often a premonitory symptom of migraine attack.