Alternate Names: Confrontation visual field; Tangent screen exam; Automated perimetry exam

How Performed: Confrontation visual field exam: A rough evaluation of the visual field may be made by the examiner sitting directly in front of you. With one eye covered, you are asked to look at the examiner’s eye and tell when you can see the examiners hand as it is moved from the periphery toward the center.

Tangent screen exam: You will be asked to sit about 3 feet from a screen with a target in the center. You will be asked to let the examiner know when you can see the target. In this method, the visual field may be mapped.

Automated perimetry: You sit in front of a concave dome and visually fixate on a central object within the dome. A computer-driven program flashes small lights at different locations within the dome’s surface, and you press a button to acknowledge whether you saw the stimulus. Your responses are compared to age-matched controls to determine the presence of defects within the visual field.

How To Prepare: Adults:
No special preparation is necessary for these tests.

Children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child’s age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child’s age:

• toddler test or procedure preparation (1 to 3 years)
• preschooler test or procedure preparation (3 to 6 years)
• schoolage test or procedure preparation (6 to 12 years)
• adolescent test or procedure preparation (12 to 18 years)

How It Feels: There is no discomfort with this test.

Risks:

Why Performed: The test will detect and measure the amount of loss in the visual field.

Normal Values: The visual field is normal in size.

Abnormal Results: Abnormal results may indicate diseases or central nervous system tumors that damage or compress the optic nerves, optic tracts, or occipital lobes of the brain. Diseases that may affect the visual field of the eye include diabetes, tumors, hyperthyroidism (a condition where the thyroid produces an excess of hormones), hypertension, and multiple sclerosis.

Additional conditions under which the test may be performed:

• Creutzfeldt-Jakob disease
• glaucoma
• optic glioma
• stroke
• stroke secondary to cardiogenic embolism
• stroke secondary to carotid dissection
• stroke secondary to cocaine

Cost:

Special Considerations: Not applicable.