Charles Bonnet Syndrome
What is the condition?
Charles Bonnet syndrome (CBS) is a common condition among people who are living with sight loss. It causes people who have lost a lot of vision to see things that aren't really there, known as visual hallucinations.
CBS can be distressing, but many people find that the hallucinations can get less frequent with time. It was initially thought that hallucinations resolved within 12 to 18 months, but a recent study found that most people still have occasional hallucinations five years after they first started.
People who have CBS may have lost a lot of their vision from an eye condition, such as age-related macular degeneration, cataract, glaucoma or diabetic eye disease. Many of these conditions are more common in older people so many people who have CBS are older.
However, anyone of any age, including children, may develop this condition as any eye condition that causes sight loss can trigger CBS. It’s thought that there are more than 100,000 cases of CBS in the UK. Some research suggests that up to 60 per cent of people who are experiencing serious sight loss may develop it.
The visual hallucinations caused by CBS can vary and can range from simple shapes and dots of colours, simple patterns, straight lines or a network of branches, to detailed pictures of people, animals, insects, landscapes and buildings. When you have lost a large amount of your vision it may be difficult to see everyday things, but you may find that your CBS hallucinations are very detailed, and much clearer than your normal vision.
The images can appear "out of the blue", lasting for just a few minutes or in some cases, several hours. At times, the hallucinations may fit alongside the background you are looking at, making them feel quite real, like seeing cows in a field when the field is actually empty or seeing a fence across the pavement. At other times, they will seem totally unreal, like seeing fantasy images such as dragons.
Types of hallucinations
The kinds of things people see with CBS hallucinations seem to fall into two broad types:
simple repeated patterns
complex hallucinations of people, objects and landscapes.
Operations / Treatment
Currently there is no medical cure for CBS. When you experience CBS, the most effective form of treatment can come from knowing that the condition is not a mental health problem or a symptom of another disease but is due to sight loss. Knowing that CBS usually improves with time (even if it doesn't go away completely) may also help you cope with the hallucinations. Having information on CBS and sharing your experiences with friends or family can also help.
Although there is no proven drug you can take to stop CBS hallucinations, some drugs for other problems have been successful in helping some people. The drugs that have been tried are usually designed for people with epilepsy, Parkinson’s disease, dementia or mental health problems.
Some common medications people take as they get older can interact when they're taken together. This can make your CBS hallucinations more frequent. If you’re not sure if the medication you’re taking is making your CBS worse, ask your GP to review your medication. This may help to lower the frequency of your hallucinations.
What do I do now?
If you have been diagnosed with Charles Bonnet Syndrome, there are many ways in which Galloway’s can help you and your loved ones come to terms with the diagnosis and can offer simple practical help with living with the diagnosis and coping with everyday life.
Galloway’s runs a support group specifically for Charles Bonnet Syndrome sufferers. To find out more about the group, or CBS in general, get in touch with our Low Vision Team on 01772 744148