What is Visual Field Testing?
Visual field testing maps your complete field of vision, including both central and peripheral areas. This test measures your eye's ability to detect light in different areas of your visual field and is crucial for diagnosing and monitoring conditions like glaucoma, retinal disease, and neurological disorders.
Why Visual Field Testing?
Your visual field is the entire area you can see while looking straight ahead. Visual field defects can occur without you noticing them, especially in the early stages of eye diseases.
Early Detection
Identifies vision loss before symptoms appear
Disease Monitoring
Tracks progression of eye conditions over time
Treatment Response
Evaluates effectiveness of treatments
Conditions Diagnosed
Eye Conditions:
- Glaucoma (most common indication)
- Retinal detachment
- Diabetic retinopathy
- Macular degeneration
- Retinal vascular occlusions
- Inherited retinal diseases
Neurological Conditions:
- Optic nerve disease
- Brain tumors
- Stroke
- Multiple sclerosis
- Pituitary disorders
How the Test Works
Setup
- Sit comfortably at the perimeter machine
- Rest chin and forehead on supports
- One eye tested at a time
- Other eye covered with patch
During Testing
- Look straight ahead at central fixation point
- Small lights flash in peripheral vision
- Press button when you see each light
- Lights vary in brightness and location
- Test takes 5-15 minutes per eye
Machine Monitoring
- Tracks your eye movements
- Monitors fixation stability
- Adjusts for reliability factors
- Provides real-time feedback
Types of Visual Field Tests
24-2 SITA Standard
Most common test for glaucoma screening and monitoring
30-2 Test
Wider field testing for advanced glaucoma or neurological issues
10-2 Test
Detailed central field testing for macular diseases
SITA Faster
Newer, quicker testing strategy with similar accuracy
Preparing for Your Test
What to Bring
- Current eyeglasses or contact lenses
- List of current medications
- Previous visual field test results if available
- Comfortable clothing for sitting still
- Allow 30-45 minutes for testing
Before Testing
- Get adequate rest the night before
- Take regular medications as prescribed
- Eat normally before your appointment
- Avoid alcohol before testing
- Inform staff of any eye pain or headaches
Important Notes
Visual field testing requires concentration and cooperation. If you're feeling unwell, tired, or unable to concentrate, consider rescheduling for more accurate results.
Understanding Your Results
Normal Results
- Full visual field with no missing areas
- Normal sensitivity throughout the field
- Physiological blind spot present (normal)
- Age-appropriate sensitivity values
- Good test reliability indicators
Abnormal Findings
- Areas of decreased sensitivity (scotomas)
- Patterns suggesting specific diseases
- Progressive loss compared to previous tests
- Generalized depression of the field
- Localized defects in specific areas
Pattern Deviation
Shows localized defects by correcting for overall sensitivity
Total Deviation
Compares your results to normal database
Reliability Indices
Measures how well you performed the test
Test Challenges
- • Fatigue during longer tests
- • Difficulty maintaining fixation
- • Learning curve for first-time patients
- • Anxiety about test performance
- • Physical discomfort from positioning
- • Droopy eyelids or glasses interference
Most patients improve with experience. Don't worry about "failing" the test.
Tips for Success
- • Stay relaxed and comfortable
- • Keep looking straight ahead
- • Press button as soon as you see any light
- • Don't worry about missing some lights
- • Take breaks if offered
- • Ask questions before starting
The technician will guide you through the process and ensure accurate results.
Frequently Asked Questions
How often do I need visual field testing?
Frequency depends on your condition. Glaucoma patients may need testing every 3-6 months, while screening patients might need it annually. Your doctor will determine the appropriate schedule.
What if I miss some lights during the test?
This is normal and expected. The test is designed to find the threshold where you can just barely see lights. Missing some lights doesn't mean you failed the test.
Can I blink during the test?
Yes, you can blink normally. However, try to keep your eye open when you hear the sound indicating a light is about to appear.
Will my results be immediately available?
Yes, the computer generates results immediately after testing. Your doctor will review them with you and explain what they mean for your eye health.
Questions About Visual Field Testing?
Our experienced technicians will ensure you're comfortable and help you achieve accurate results.
Schedule Your Test