What Brain Scans Will I Receive During a Dementia Test?

Written by Active Minds on Wednesday the 27th of June 2018.


If you are concerned that you or a loved one are starting to show signs of dementia, then the first port of call is a visit to the GP. After the initial assessments, such as blood tests, are carried out and other causes for the symptoms are ruled out, you will be offered a brain scan. These scans cannot solely diagnose dementia but are used as part of a wider assessment. They may also be used to rule out other causes for the symptoms, such as a stroke or brain tumour.


There are generally three types of brain scans used to help diagnose dementia:


CT Scan

A computerised tomography scan, better known as a CT scan, looks at a portion of your brain in finite detail. It shows if the brain has shrunk in certain areas and whether strokes have occurred, which can often be a sign of vascular dementia. It will also look for evidence of a brain tumour. CT scans are unable to give detailed information about the structure of the brain.



MRI’s provide detailed imaging of your brain. They can offer more information about any blood vessel damage that may occur in vascular dementia, and more detailed information about strokes or tumours. MRI’s are also used to confirm a dementia diagnosis and the type of disease that is causing the dementia, as well as the damage this has caused to the brain. E.g. if a person has been diagnosed with Alzheimer’s, an MRI can show the damage that has already occurred in the brain that is associated with Alzheimer’s disease. However an MRI cannot diagnose Alzheimer’s with certainty on its own as yet, although brain scans are continuing to improve.


SPECT scan or PET scan

If the results of a MRI or CT scan are uncertain, then a SPECT or PET scan may be offered. This scan shows how the brain functions and looks at the blood flow. It can pick up areas of the brain that more or less active than others which can help determine which areas, if any, are affected by dementia.

If dementia is diagnosed, whilst, understandably, this is a distressing result, it is important that you continue to engage your loved with dementia in meaningful therapeutic activities for dementia. This will help keep their brain active, and ensure that they feel valued and loved.