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http://www.stc-access.org/2009/01/23/charles-bonnet-syndrome-phantom-vision/

Charles Bonnet Syndrome (phantom vision)

For an informative article about phantom vision, which affects between 10 and 40 percent of people with low vision, read the article on Lighthouse International, “I See Purple Flowers Everywhere: The Many Visions of Charles Bonnet Syndrome” by Lylas G.Mogk,MD, and Marja Mogk, PhD; with Carol J. Sussman-Skalka,CSW, MBA.

Do you ever see things you know are not there but look real anyway? It’s a common side effect among people with vision impairment. While we refer to it as “phantom vision,” the technical term is “Charles Bonnet Syndrome.” If you’ve experienced this, rest easy. Your mind is fine. It’s your eyes that are playing tricks on you.

What Exactly Is Charles Bonnet Syndrome?Charles Bonnet, an 18th century Swiss naturalist and philosopher, is credited as the first person to describe the syndrome. Like his grandfather, who had low vision and saw men, women, birds and buildings he knew were not there, Charles experienced similar phantom visions when his own vision deteriorated.

One explanation compares this condition to phantom limb experiences. People who have a limb amputated may still feel their toes or fingers, or may experience itching on an arm that is not there. This happens because the limb’s nerves are still active and sending signals to the brain, which the brain interprets as sensations from the missing limb. Similarly, when retinal cells become impaired and are no longer able to receive and relay visual images to the brain, the visual system begins firing off images on its own.

Often, these images are not related at all to a person’s life. Sam, who has macular degeneration, said, “I see little monkeys with red hats and blue coats playing in the front yard.” Sam had no doubt that the monkeys he saw were not real ones. As a result, he wasn’t concerned about his mind. However, he was worried about what others would think, so he kept it to himself…

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The article continues on to explain the percentage of people who may be affected by Charles Bonnet Syndrome and that it is not a psychiatric problem. The article describes some of the images seen that patients have reported.

A majority of people do not find their phantom vision disturbing, probably because the images they see are amusing, pleasing or entertaining…

This article is based on, and includes quotes from, a chapter in Macular Degeneration: The Complete Guide to Saving and Maximizing Your Sight, written by Lylas G. Mogk, MD, and Marja Mogk, PhD, published by The Ballantine Publishing Group (2003).

This article appeared in Sharing Solutions - Fall 2004 Edition

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http://www.lighthouse.org/aboutus/newsletters/sharing-solutions/fall-2004/purple-flowers/

"I See Purple Flowers Everywhere: The Many Visions of Charles Bonnet Syndrome"
by Lylas G.Mogk,MD, and Marja Mogk, PhD; with Carol J. Sussman-Skalka,CSW, MBA.

Do you ever see things you know are not there but look real anyway? It's a common side effect among people with vision impairment. While we refer to it as "phantom vision," the technical term is "Charles Bonnet Syndrome." If you've experienced this, rest easy. Your mind is fine. It's your eyes that are playing tricks on you.

What Exactly Is Charles Bonnet Syndrome?

Charles Bonnet, an 18th century Swiss naturalist and philosopher, is credited as the first person to describe the syndrome. Like his grandfather, who had low vision and saw men, women, birds and buildings he knew were not there, Charles experienced similar phantom visions when his own vision deteriorated.

One explanation compares this condition to phantom limb experiences. People who have a limb amputated may still feel their toes or fingers, or may experience itching on an arm that is not there. This happens because the limb's nerves are still active and sending signals to the brain, which the brain interprets as sensations from the missing limb. Similarly, when retinal cells become impaired and are no longer able to receive and relay visual images to the brain, the visual system begins firing off images on its own.

Often, these images are not related at all to a person's life. Sam, who has macular degeneration, said, "I see little monkeys with red hats and blue coats playing in the front yard." Sam had no doubt that the monkeys he saw were not real ones. As a result, he wasn't concerned about his mind. However, he was worried about what others would think, so he kept it to himself.

Is the Syndrome Common?

Studies show that Charles Bonnet Syndrome affects between 10 and 40 percent of people with low vision. Our research suggests that it is more likely to appear if you have visual acuity between 20/120 and 20/400. If your vision falls within these parameters, your eyes still have a great deal of power, even though they aren't receiving or sending as many images as previously. As a result, your eyes may be providing additional images of their own.

We can't predict whether you will see images and, if you do, how frequently they will occur or how long they will last. You may never experience Charles Bonnet Syndrome, you may have it for only a few months, or you may have it for years. You may see images everyday, a few times a week or several times a month.

Are You Sure This Is Not a Psychiatric Problem?

Yes! Charles Bonnet Syndrome is no more than a side effect of vision loss. The six criteria for Charles Bonnet Syndrome (outlined by Naville in 1873 - and still applicable today) can help you determine whether or not you are experiencing phantom vision. Ask yourself whether the images you see have the following six characteristics:

They occur when you are fully conscious and wide awake, often during broad daylight.
They do not deceive you; you are aware that they are not real.
They occur in combination with normal perception. For example, you may see a sidewalk clearly but find it covered with dots, flowers, or faces.
They are exclusively visual and do not appear in combination with any sounds or bizarre sensations.
They appear and disappear without obvious cause.
They are amusing or annoying but not grotesque.
"Since ophthalmology has paid so little attention to Charles Bonnet Syndrome, many doctors don't realize how common it really is, and some may not be familiar with it at all."

What Do People Actually See?

Patients "have reported seeing cartoon characters, flowers in the bathroom sink, hands rubbing each other, waterfalls and mountains, tigers, maple trees in vibrant autumn foliage, yellow polka dots, row houses, a dinner party and brightly colored balloons. Many people see faces or life-size figures that they've never seen before. One of the most remarkable qualities of these figures is that they almost always wear pleasant expressions and often make eye contact with the viewer. Menacing behavior, grotesque shapes and scenes of violent conflict are not, to my knowledge, a part of the syndrome.

"Usually the same image or set of images reappears to each person, sometimes in the same places or at the same time of day. Sam's monkeys usually materialized around sunset, cavorting across the lawn or around the big blue easy chair by the fireplace. They stayed for ten or 20 minutes several times a week for two years and then began to appear less frequently. ... Sometimes the images are exactly to scale and sometimes larger or smaller than life. ... Joe's horses looked like children's toys at a distance of ten feet, but as they galloped outside they became Clydesdales and then stallions worthy of Gulliver."

Rosa saw "flowering trees" with large, beautiful pink flowers. She knew that they weren't real because it was autumn. But when she told a friend what she was seeing, her friend was not convinced with Rosa's explanation. Rosa stopped telling people about her visions. She acknowledged, "You have to be careful what you say."

"Sometimes Charles Bonnet Syndrome images can become confused with dream images. For example, several of my patients have reported frightening moments when they thought they saw a man standing in their bedroom or hallway. These men, however, were often darkclad or indistinct figures that appeared as the patient was relaxing on a couch, dozing or in bed waiting to fall asleep, or just awaking. These figures were probably residual dream images. ... They are not typical of Charles Bonnet Syndrome."

Is Charles Bonnet Syndrome Treatable?

A majority of people do not find their phantom vision disturbing, probably because the images they see are amusing, pleasing or entertaining. You may want to discuss your phantom vision with your doctor, particularly if you feel bothered or distressed by your experiences. While there does not seem to be any specific medications that work for everyone, many people find that learning more about the condition helps to reassure them. Buddy's "purple flowers" appeared in his bathroom and on his clothing. He got a chuckle when he imagined what golf pants with purple flowers would look like to other people. He had a cousin with macular degeneration who saw frogs in his bathtub and a very attractive woman stationed on his back porch. Buddy's purple flowers didn't compare to the woman on Harry's porch; and Harry, though disappointed that his "vision" was not real, found that he enjoyed it quite a lot!


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This article is based on, and includes quotes from, a chapter in Macular Degeneration: The Complete Guide to Saving and Maximizing Your Sight, written by Lylas G. Mogk, MD, and Marja Mogk, PhD, published by The Ballantine Publishing Group (2003).


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This article appeared in Sharing Solutions - Fall 2004 Edition