Charles Bonnet Syndrome - Causes, Symptoms, Diagnosis, and Management

What Is Charles Bonnet Syndrome?

Charles Bonnet syndrome (CBS) occurs when someone suddenly loses their vision and starts seeing things that are not present. These are called visual hallucinations. Any mental illness does not cause these hallucinations, which are an effect of diminishing eyesight. The brain tries to fill the gaps with them when the eyes no longer send clear pictures.

What Causes CBS?

When the eye stops sending signals or visual images, the brain, still active, needs to process something. So, it begins replaying stored images from memory. This is the brain's way of compensating for missing input. For example, the brain creates pictures of people, animals, or patterns in someone with severe vision loss. These images are only phantom images made by the brain.

What Risk Factors Contribute to the Formation of Charles Bonnet Syndrome?

Certain eye issues make it more likely for a person to develop CBS.

They are:

1. Degeneration of the Macula- This can lead to age-related loss of vision.

2. Cataracts- This results in a cloudy lens.

3. Myopia- Short-sightedness.

4. Glaucoma- Increased eye pressure damages the optic nerve.

5. Diabetic Retinopathy- Due to high sugar, there is damage to the blood vessels in the eye.

6. Blood Vessel Issues- Blocked or damaged blood vessels in the retina.

7. Surgery- Eye surgical procedures.

Some other risk factors include:

1. Social Isolation- When a person is usually alone, he is more likely to develop CBS.

2. Reduced Cognition- When there is a decrease in the capacity of a person to comprehend information.

Who Is at More Risk of Acquiring Charles Bonnet Syndrome?

Charles Bonnet syndrome mainly affects the elderly because vision problems are common with age. However, it can also affect younger people with severe vision loss. Both men and women can get it, though some studies suggest women may be slightly more prone.

What Are the Symptoms of CBS?

CBS may look very different from person to person, as it can occur in many clinical forms.

Firstly, based on the type of hallucinations, there are two types:

• Simple Hallucinations: The person sees flashes of light, shapes, and patterns.

• Complex Hallucinations: In these, the person can see detailed pictures of animals, buildings, people, and even movements. They find it challenging to get around due to disorientation about the distance between objects.

Secondly, based on the frequency of hallucinations, there are three types:

• Episodic Hallucinations: The hallucinations come and go, then stop.

• Periodic Hallucinations: Here, the visions appear repeatedly in a pattern.

• Continuous Hallucinations: Here, the visions stay for longer stretches.

The visions seen by the patient are mostly not frightening or distressing. In addition, in some patients, the CBS delusions are triggered by fatigue, bright light, and stress. Usually, they appear clear and detailed, but the patient knows they aren’t real.

How Does CBS Differ from Mental Illness or Dementia?

In mental illness or dementia, people believe their hallucinations are real and may act on them. At the same time, CBS patients usually know that what they see is not real. They don’t lose touch with reality; they just see images. This awareness helps in diagnosis.

How Is CBS Diagnosed?

Charles Bonnet syndrome lacks a definite diagnostic procedure. Instead, doctors conclude the condition by:

• Taking a complete medical history and drug history from the patients.

• Eye examination.

• Sometimes, CBS radiology imaging may be needed to rule out CBS strokes and brain issues.

• Psychological tests rule out severe mental illnesses like dementia and Alzheimer's.

CBS is diagnosed once other serious causes are ruled out.

What Treatment or Management Options Exist for CBS?

Charles Bonnet syndrome does not have a specific treatment strategy. Sometimes, the hallucinations resolve by themselves. However, other underlying causes of CBS remain to be solved. No medications help in Charles Bonnet syndrome treatment.

Doctors usually focus on:

• Reassurance: Letting patients know it is not a mental illness.

• Management of Underlying Cause (Eye Problem): Eye issues, like cataracts or glaucoma, are identified and appropriately treated.

• Coping: Blinking, moving eyes to the sides, adjusting the lights, or focusing on other tasks.

In rare cases, if hallucinations cause extreme distress, medications like antipsychotics may be tried, but side effects often outweigh benefits.

What Is the Prognosis of CBS?

CBS does not shorten life and does not usually lead to blindness or mental illness. Sometimes, hallucinations might resolve themselves. Charles Bonnet syndrome, as such, does not cause any severe complications. However, patients suffering from the disease often have emotional complications. They suffer from anxiety, fear, and depression when talking about their experience. Support from doctors and family can make a huge difference. Research linking CBS with the increase in mortality rate and dementia is present. However, there is a lack of substantiating evidence.

Can CBS Be Prevented or Minimized?

Since CBS is linked to vision loss, the best prevention is keeping eyes healthy. Regular eye checks, timely treatment of glaucoma or cataracts, and managing health conditions can help.

While CBS cannot always be prevented, its impact can be reduced with healthy lifestyle changes:

• Good lighting at home.

• Avoiding long periods of isolation.

• Stress management and enough sleep.

How Do People Live with CBS?

Living with CBS is about understanding and adapting. People cope better when they know their hallucinations are harmless. People are reassured about the non-serious nature of hallucinations and made familiar with their surroundings.

People are encouraged to adopt self-help measures such as

• Restful sleep and relaxation.

• Low vision practice. In addition, they are motivated to contact their physicians, family members, and friends about their problems.

• Patients are advised to go for a regular eye checkup and avoid sudden changes in the lighting.

• Eye exercises such as

  • Eye movements in all directions.

  • Rapid eye blinking while staring long at objects. These measures help improve the symptoms in some patients.

• Avoid stressful conditions that aggravate the disease.

Conclusion:

Charles Bonnet syndrome is a rare and challenging eye disease. The underreporting and lack of awareness of the disease entity diminish the patient's quality of life. Therefore, proper diagnosis of the condition followed by patient reassurance remains the mainstay of treatment.

Key Takeaway From iCliniq

• CBS is not a mental illness but rather a consequence of a vision problem and the brain’s compensation for it.

• CBS is underreported in around 1 to 10% of people with severe vision problems.

If you or a loved one has vision loss and starts seeing things that aren’t real, don’t panic. You can consult our eye specialist for management.