Brain scans, such as MRI (magnetic resonance imaging) or CT (computerised tomography), can help to rule out other causes of dementia.

To help make a specific diagnosis of DLB, a type of scan called a SPECT scan (or 'DaTscan') may be used.

This type of scan can show changes in the brain that are more common in this type of dementia. However, people with very clear-cut symptoms of DLB or PDD may not need these tests.

While hallucinations are common in DLB, they can also occur in conditions like Charles Bonnet syndrome, which affects people who are losing their sight. This condition is not well known, so people who have it may worry they are developing dementia. Find out more at or call 0345 051 3925.

It is important to get the right diagnosis so that the right treatments and help can be given. If you are worried about your health or someone else’s, you should talk to your doctor.

If the doctor suspects dementia, you may be referred to a memory clinic or another specialist clinic. You will be asked about your symptoms and medical history and may have a physical check-up and memory and thinking tests. You may also have tests like brain scans and blood tests. Together these tests will help to identify the likely cause of your symptoms.

Dementia with Lewy bodies

Information in this booklet is for anyone who wants to know more about dementia with Lewy bodies (DLB). This includes people living with DLB, their carers, families and friends.


Order health information

Alzheimer’s Research UK has a wide range of information about dementia. Order booklets or download them from our online form.

This information was updated in December 2019 and is due for review in December 2021. It does not replace any advice that doctors, pharmacists or nurses may give you. Please contact us if you would like a version with references.

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Dementia Research Infoline

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