What does hom*onymous hemianopia look like?
Hemianopia affects one side of your visual field, left or right, in both eyes at the same time. It can be hard to tell that it’s affecting both eyes at the same time unless you specifically test your vision one eye at a time (a healthcare provider usually tests for this as part of a physical exam, but you may also notice it yourself).
Healthcare providers often describe the symptoms as “positive” or “negative.” That doesn’t mean good and bad in this context. Instead, it can mean the following:
- Negative symptoms (loss or decrease in ability). If the effect from hom*onymous hemianopia is negative, you might have dimmed vision or half of your visual field looks dark or blacked out. These symptoms usually mean the affected area isn’t working as well as it should or at all.
- Positive symptoms (new or additional effect). Positive symptoms of HH can look like a bright fog or haze, distortions or flashes in the affected part of your vision. These symptoms usually indicate the affected area is still working, but it’s malfunctioning, like with a seizure or migraine.
What can I do to help myself manage long-term hom*onymous hemianopia?
If HH is likely to be a long-term or permanent issue for you, there are many things you can do to help yourself adapt to the condition or compensate for it. A low-vision specialist or visual rehabilitation provider can guide you through specific exercises and approaches.
Strategies to improve reading ability include:
- Use a straight edge (like a bookmark or ruler) to direct your eyes to the next line of text.
- Work on willingly increasing the size of small eye movements as you read words along each line of text. You want to “capture” each word in your field of vision and recognize it as a whole word before reading it.
- Place your hand at the edge of the page so it’s easy to tell where the margins are.
- Hold the text at a 45-degree to 90-degree angle so that you read vertically instead of horizontally. If your vision loss is on the right, you should read downward. If it’s on the left, you should read upward. Reading in a specific direction keeps the next line of text in your field of vision.
Strategies to improve navigating the world around you include:
- When walking or moving around, learn to direct your eyes toward the good side of your visual field.
- When walking into a new environment, pause and rotate your head to scan the area through the good part of your field of vision. Observe where objects and people are, and mentally recreate a picture of what you see. Practicing this, particularly within the first six months after vision loss, can help train your brain so you do this automatically.
- When looking for objects that might be in the missing area of your vision, consciously make large eye movements to that side and then let your eyes come back to the object.
- When walking, let a partner walk on the blind side and provide their arm for guidance.
- When you’re in group situations, try to stand or angle yourself so people are visible in your working visual field as much as possible.
- When in a theater, sit as far as you can on the same side as the missing area of your visual field. That maximizes how much of the action stays where it’s easier for you to see it.
- Play real-life (not computer-based) card games and do crossword puzzles to regain and improve hand-eye coordination.
- Do word search or picture search puzzles to improve eye scanning at near distances.
Other treatments or techniques your provider might recommend include:
- Prisms on glasses (either integrated into the lenses or in special lens attachments) may help expand the center of your vision. Prisms change how objects appear, which can help you compensate for the missing area of your vision.
- Driving is hazardous for many people with hom*onymous hemianopsia, particularly if you have other brain-related issues or symptoms. Talk to your provider about whether you can and should drive. You may also need to practice on a driving simulator or pass a test with an instructor, who’ll determine if you can still drive safely.
- Some makers of computer-assisted programs claim to promote recovery of your entire field of vision. But not all these claims are accurate, and these programs can be expensive. Talk to your healthcare provider or specialist about whether these programs are legitimate or where you can find programs that can help.
A note from Cleveland Clinic
It’s understandable if you feel scared or confused if you can suddenly see only half of the world in front of you. hom*onymous hemianopia can signal severe, even dangerous conditions. That’s why it’s important to act to take care of yourself.
If you’ve never experienced this before, get emergency medical care immediately by calling 911 or your local emergency services number. If you have a condition that can cause this symptom, the healthcare provider who diagnosed you can guide you on how to react. And when in doubt, get medical care right away. Many conditions that cause this are reversible if you act quickly.
