Visual Field Analysis
Interesting Eye Articles
18 October 2018
Visual Field testing is an important diagnostic tool in the assessment of the eye’s visual fields. A normal visual field as measured from the central fixation point is 90 degrees temporally, 50 degrees nasally, 50 degrees superiorly and 60 degrees inferiorly. Many eye conditions can cause a narrowing of the field of vision, examples are Retinitis Pigmentosa, Glaucoma, etc. Other conditions for example Macular degeneration will only affect central vision. Even space occupying lesions, for example tumors in the brain may cause abnormal patterns in the visual fields.
When looking straight ahead, you should be aware of what objects are to the right and left of your fixation point. If you are approached from the side by a friend, you should be aware of his approach. This awareness is your field of vision.
Most patients are unaware of reducing field of vision as this happens so gradually. Another reason is what one eye missed, the other eye sees.
The instrument will project light at your peripheral field, while you look straight ahead. If you are able to see the spot of light, you press a button. It also tests the sensitivity of your retina to light by presenting different intensity of light.