A brain injury can cause the loss of over 50% of your visual field, this is known as hemianopsia.
Males from the ages of 50 to 70 are most frequently affected by this condition.
Over 70% hemianopsias are caused by a blockage of the blood supply in the brain, most frequently due to a tumor or stroke.
What is hemianopsia?
Hemianopsia, sometimes called hemianopia, is the loss of sight in up to half of your field of vision.
Imagine taking a pen and drawing a line across the middle of your vision. Now imagine that you can’t see anything at all on one side of that line, this is what many people who have hemianopsia experience.
The loss of half of your vision dramatically affects the quality of life, imaging trying to get through the day with half of your vision missing.
Schedule an appointment with a low vision eye doctor near you to maximize your remaining vision to improve your quality of life.
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What are the causes of hemianopsia?
Hemianopsia can occur when there is damage to the optic nerves, optic chiasm or visual processing regions of the brain.
Strokes are the most common cause of vision loss in patients with hemianopia. However, inflammation, head injuries and cranial tumors can all be a cause as they affect the blood flow in the brain.
When any part of this system is damaged it can result in partial or complete loss of vision in up to half the visual field.
What are the symptoms of hemianopsia?
Symptoms may include:
- Bumping into objects while walking, such as furniture, door frames and people
- Difficulty driving, especially when changing lanes or attempting to avoid objects on the side of the road
- Difficulty finding or reaching for objects on desks or countertops, or in closets and cabinets
- Frequently losing your place while reading or having trouble finding the start or end of a line of text
- Sensation that something is wrong with your vision
If you suspect you may have hemianopsia, contact a low vision eye doctor near you.
How is hemianopsia treated?
The treatment an eye doctor will recommend depends on the extent of vision loss and the condition causing the hemianopsia.
In some cases, if blood flow is restored the hemianopsia may improve over time. However, where neural damage has occurred in the brain, hemianopsia is usually permanent, but there are still options eye doctors may be able to recommend.
There are several ways that eye doctors can help improve vision, including:
1. Side-Vision Awareness Glasses (SVAG)
SVAG provides improved vision by offering a wide viewing area. They have a vertical edge that enables a person with hemianopsia to move their eyes just a few millimeters to access the SVAG area of the lens.
2. Vision restoration therapy (VRT)
VRT works by repeatedly stimulating the edges of the missing field of vision. Since the adult brain has some ability to rewire itself, VRT causes the brain to grow new connections around the damaged areas to restore some lost functions.
3. Visual field expander aid
Special glasses can be fitted with a prism in each lens. These prisms bend incoming light so that it reaches the non-damaged section of the visual field.
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If you have experienced a stroke or other brain injury and are experiencing loss of vision, schedule an eye evaluation with an eye doctor near you.
An eye doctor experienced in low vision might just be able to allow you to experience a higher quality of life and get back to enjoying the vision you have.