Metamorphopsia

What is metamorphopsia?

A metamorphopsia is a distortion in your vision that changes the way you see things. It’s a symptom that can make things look bigger, smaller or misshapen. Metamorphopsias are possible with both eye and brain conditions and issues.

Healthcare providers, especially an eye care specialist and/or a neurologist, can help you better understand how and why these changes are happening. They can also guide you on how to manage the conditions causing metamorphopsias in your vision and how to tell when you need emergency medical care. Last but not least, they can reassure you and help you process what you’re experiencing, so it does less to disrupt your life.

What do metamorphopsias look like?

Metamorphopsias distort the way things look to you. They can look bigger, smaller, farther away or closer. They can also distort your vision, like looking through a pair of eyeglasses with a strong prescription that isn’t correct for your eyes.

Some metamorphopsias will distort larger areas of your vision, while others will only partially distort objects you look at. It varies widely, and the metamorphopsias you see can be completely different from those that others experience.

What are the most common causes of metamorphopsias?

Depending on why they happen, metamorphopsias can be a minor annoyance or a sign of serious problems. There are three main sources of metamorphopsias:

• Refraction conditions and changes (most common).
• Retinal changes and conditions.
• Brain-related conditions (least common).

Refraction conditions and changes

Your eye bends (refracts) light as it enters and passes through. That bending is supposed to focus light beams precisely on your retina. The more precise the focus, the clearer you see. Refractive errors are when that refracting doesn’t happen correctly. Examples include:

• Strong or severe refractive errors like astigmatism.
• A large difference in prescription strength needs between your eyes (anisometropia).
• Cornea or lens shape changes/differences.
• New corrective lenses (like eyeglasses or contacts), especially with bigger changes to how you see.

Retinal changes and conditions

The retina at the back of your eye has a light-detecting layer of cells (photoreceptors). Part of how they work is due to the shape of your retina, which needs to lay flat against the layer underneath.

Wrinkles, holes or other retinal changes can cause metamorphopsias when they change the shape or position of your retina. Metamorphopsias are more severe when they happen in the macula, the part of your retina responsible for detecting color and fine details.

Your retina needs light to arrive with precise timing, so changes in your retina’s shape distort what you see if the light arrives too early. And if the changes in your retinal shape or position are severe, it can destroy the connections that let your retinas send light-related signals to your brain. When that happens, it can cause permanent vision loss or even blindness.

Retinal and retina-related conditions that can cause metamorphopsias include:

• Age-related macular degeneration, especially the wet form.
• Central serous retinopathy.
• Chorioretinopathy conditions like chorioretinitis.
• Cystoid macular edema.
• Diabetes-related retinopathy and diabetes-related macular edema (swelling).
• Macular pucker.
• Ocular migraine.
• Retinal bleeding (hemorrhage).
• Retinal tears or detachments.
• Retinitis pigmentosa.
• Uveitis, including choroid inflammation from infection-related conditions like presumed ocular histoplasmosis syndrome.

Brain-related metamorphopsias

Metamorphopsias can also happen because of conditions or issues that affect your brain. Your retinas detect light, but they don’t actually form the picture of the world that you see. Instead, your retinas transmit information about the light they detect through your optic nerve to your brain.

Once your brain gets that information, it processes the signals and uses them to build your big-picture view of the world. And if the processing and picture-building don’t happen correctly, that can cause the kinds of distortions that you “see” with metamorphopsias.

Some brain-related conditions that can cause metamorphopsias include:

• Alice in Wonderland syndrome.
• Drugs (including nonmedical and prescription drugs), especially hallucinogens and drugs with hallucinogen-like effects like dextromethorphan or ketamine.
• Migraine headaches, especially migraines with auras.
• Seizures (including those from epilepsy).
• Strokes and transient ischemic attacks (TIAs).

Several other brain-related conditions can cause metamorphopsias, but research to confirm this is limited. That’s because metamorphopsias are usually temporary and generally last for brief periods only.

How is this symptom treated?

There’s no way to treat metamorphopsias directly. Instead, treatments focus on whatever’s causing the metamorphopsia whenever possible. That can vary depending on whether your metamorphopsia is from an eye-related or brain-related condition.

But some types of metamorphopsia happen for reasons that aren’t treatable. Your eye care specialist, neurologist or another provider can tell you more about treatments for your specific case and needs.

What can I do at home to treat metamorphopsia?

It takes a trained healthcare professional to tell what’s causing your metamorphopsias and whether or not it needs emergency treatment. And providers usually need to run specific tests to determine the cause of your case, especially whether it’s an eye or brain issue. Because of that, you shouldn’t try to self-diagnose or self-treat metamorphopsias the first time you have one.

If you have a diagnosed condition that can cause metamorphopsias, you should talk to your healthcare provider about what’s causing them. Your provider can tell you more about how to tell when you need emergency care and when you can treat yourself using medications or treatments they prescribe.

But when in doubt, it’s safest to get medical attention quickly. Many of the conditions that can cause metamorphopsias are emergencies because time is a factor. That means they become more dangerous or less treatable — or both — the longer you wait.

Can metamorphopsia be prevented?

It depends on the cause. Some conditions that cause metamorphopsias happen unpredictably and aren’t preventable. But many conditions — like migraines, seizures and strokes — may be preventable. And even if they aren’t 100% avoidable, you may be able to reduce your risk of them happening. Your healthcare provider or eye specialist is the best person to tell you if you can prevent or reduce your risk of having metamorphopsias and the conditions that cause them.