Visual Field Testing
- Mar 3
- 2 min read
Visual field testing aims to test the sensitivity of the peripheral retina, that is, how good the side, paracentral, or surrounding vision is. This is important as any changes or loss in periphery vision can go undetected by the person him/herself - this is because any loss or reduction in our central vision is easily 'seen' by us, but not for our 'side vision'.
Reasons for Doing Visual Field Testing:
Visual field testing is performed to:
1. Detect and Monitor Glaucoma
Glaucoma causes progressive peripheral vision loss
Damage often occurs before noticeable symptoms
Through this visual field testing, we can detect functional loss from optic nerve damage
2. Assess Neurological Conditions
Brain tumors
Stroke
Pituitary lesions
Multiple sclerosis
Specific patterns (e.g., hemianopia, quadrantanopia) can help localize lesions in the brain.
3. Monitor Retinal Diseases / Conditions
Retinitis pigmentosa
Retinal detachment
Macular disease
4. Assess Unexplained Visual Complaints
Missing areas of vision
Difficulty navigating
Frequent bumping into objects
For these symptoms, visual field testing helps objectively confirm and monitor functional vision loss, better allowing us to make a diagnosis and come up with a management plan.
5. Occupational and Driving Requirements
Some professions and driving standards require documented visual field assessment, such as the Esterman Visual Field test.
Importance of Visual Field Testing
1. Early Detection of Disease
In glaucoma especially, functional loss can be detected before patients notice symptoms.
2. Monitoring Progression
Repeated or follow-up visual field tests allow us to track if the visual field (and eye conditionor disease) is stable or deteriorating, hence allowing us to adjust treatment plans and medications accordingly.
3. Better understanding
Provides objective record of visual function that can be better used to help a patient understand the extent and type of visual field loss.
4. Preventing Irreversible Vision Loss
Many causes of field loss are permanent once damage occurs, making early detection critical.
How the Test Is Typically Performed
The patient places their chin on a rest.
One eye is tested at a time, with the other eye occluded
They fixate on a central target light.
They press a button when they see light flashes in the periphery.
The test takes about 4–8 minutes per eye, and the other eye is tested once the first eye is done.
Visual field testing using devices like the Optopol PTS 2000 and Humphrey Field Analyzer 3 is a critical diagnostic tool in modern eye care. It is a cornerstone investigation in both community optometry and hospital-based ophthalmology, helping prevent avoidable vision loss through early detection and careful monitoring.
