Central vision allows us to perceive fine details directly in front of us and is primarily controlled by the macula, a small area at the center of the retina. This region contains a high concentration of photoreceptor cells, which detect color and light intensity. Impairment of central vision can significantly affect activities requiring precision, such as reading, writing, recognizing faces, and driving.
What causes central vision loss?
There are multiple factors and conditions that can lead to central vision loss, includes:
Macular degeneration: This is the most common cause of central vision loss.
Diabetic retinopathy: High blood sugar levels that cause damage to the retina by altering the function and structure of its blood vessels.
Macular edema: Fluid build-up within the macula that blurs your vision.
Macular holes: A small tear in the macula that is usually developed as part of the natural aging process.
Glaucoma: Typically linked to peripheral vision, but it can sometimes also lead to central vision loss in advanced stages.
Brain tumors: Brain tumor growth can put pressure on the optic nerve, which can sometimes cause central vision loss, along with other visual field deficits.
Symptoms of central vision loss
Often, the first symptom of central vision loss is a small dark spot in the center of your field of vision. Other symptoms include:
- straight lines appearing wavy or crooked.
- objects appear hazy or blurry, making it difficult to see details properly.
- difficulty adapting to low light causes one to experience difficulty seeing in dimly lit rooms or at night.
- trouble differentiating between colours and colours may look faded or less bright than normal.
- difficulties recognizing faces
While regular eye exams with an eye care professional are essential, there is a simple way to check your vision at home. The Amsler grid test is primarily used to test your central field of vision. To do this test, you will check each eye separately. Wearing any glasses you normally use to read and hold the grid about 14 inches away from your face. Cover one eye and focus on the dot in the middle, and you should be able to see the horizontal and vertical lines in the grid as straight and unbroken. If you are unable to see where the lines intersect, or if any lines or areas look blurry, wavy, dark or blank, this could mean that you have a blind spot in your field of vision and contact your ophthalmologist right away.
Picture 1 – Amsler Grid
Picture 2 – For those with vision loss, the Amsler grid may appear distorted, with wavy lines or missing areas.
