Tests for Diagnosing Dementia

Tests for Diagnosing Dementia

With 50 million people around the world living with some form of dementia, accurate dementia screening tests are more important than ever. Because dementia can have a major impact on an individual’s career, family, functional abilities and independence, an early diagnosis can be crucial for addressing the disorder quickly and effectively.

If you or a loved one may have dementia, it’s helpful to understand what dementia is, common symptoms of the disease and the imaging tests typically used to discern a dementia diagnosis. With this knowledge, you can find out more details about the options for treating the condition.

What Is Dementia?

Dementia is not a single disease, but rather, it is a general term for the loss of memory, language, problem-solving skills or other cognitive functions and thinking abilities. Like the term heart disease, dementia refers to a broad range of more specific medical disorders and conditions, like Alzheimer’s disease. The cognitive disorders that fall within the category of dementia are caused by irregular brain changes.

These abnormal changes in the brain are what lead to a downturn in thinking skills, which may affect behavior and feelings and often has an impact on relationships. Alzheimer’s is the most common cause of the condition, accounting for 60% to 80% of dementia cases. The second most common cause of dementia is known as vascular dementia. This condition stems from microscopic brain bleeding and blood vessel blockage.

It’s possible for patients to experience brain changes stemming from multiple types of dementia at the same time, which is called mixed dementia. Indications of dementia can vary greatly, and some conditions that might seem like dementia symptoms may be linked to other causes that are more easily reversible — such as a vitamin deficiency or thyroid problems.

In general, the term dementia is applicable when the following symptoms become severe enough to interfere with everyday life:

  • Struggling with short-term memory
  • Problems keeping track of a wallet, phone, purse or keys
  • Forgetting to pay bills
  • Difficulty remembering appointments and meetings
  • Neglecting to plan or prepare meals
  • Roaming outside of the neighborhood at inappropriate times

Although dementia can often be referred to as senility or senile dementia, these terms are incorrect and wrongly imply that serious mental decline and the symptoms listed above are a normal part of aging. Dementia is a serious disorder that involves more than occasionally misplacing the car keys. For those who begin showing signs of dementia, there is a variety of tests to help diagnose the condition.

Common Tests Used to Diagnose Dementia

Patients and doctors can choose from a range of tests to determine the root cause of potential dementia symptoms. Although receiving a positive result for a preliminary dementia screening test may not definitively diagnose a patient with the disease, it can strongly indicate whether dementia is the most likely cause of their symptoms. Some dementia screening tests can also dismiss other possible causes and point toward the correct diagnosis.

The most informative techniques of screening individuals for dementia include:

  • Family history review
  • Mental ability tests
  • Neurological exams
  • Blood tests
  • Genetics tests
  • Brain imaging

While many tests for dementia can rule out other medical problems, a brain imaging test is one of the most reliable ways to verify a dementia diagnosis.

Brain Imaging Tests Used to Diagnose Dementia

Although a brain scan alone does not diagnose dementia, it can be a strong indicator when included as part of a wider assessment. Once simpler tests, such as blood tests and mental ability tests, have been used to eliminate other possible conditions, a brain scan can confirm dementia as the patient’s diagnosis.

In addition to helping diagnose dementia, a brain imaging test can check for other potential causes of common dementia symptoms, such as a brain tumor or stroke. If the symptoms are coming from a different source, they will require a different treatment, so an accurate diagnosis is imperative. With imaging tests, patients can be more confident they are receiving the correct treatment and following the right recovery plan.

While there is a variety of brain imaging tests patients could undergo, below are the most common for diagnosing possible cases of dementia.

brain imaging test scan

1. MRI

magnetic resonance imaging (MRI) scan is a standard structural imaging test for potential Alzheimer’s patients. An MRI can help the patient and their doctor affirm that symptoms are attributable to dementia, not another cause like damage from severe head trauma. In some cases, a dementia MRI can show whether the patient has high levels of beta-amyloid, which is a notable sign of Alzheimer’s.

An MRI can provide detailed information about any blood vessel damage that may be due to vascular dementia. In addition, the MRI scan can point to shrinkage in particular sections of the brain. For instance, shrinkage may occur in both the frontal and temporal lobes if the patient has frontotemporal dementia, whereas typically only the temporal lobe is affected by the beginning phases of Alzheimer’s disease.

One particular type of MRI, the functional MRI (fMRI), is commonly used by doctors to examine damage done by Alzheimer’s disease. Because an fMRI looks closely at the anatomy of the brain to show which parts of the brain are handling essential functions, this scan can help doctors examine the key movement and language control areas of the brain to come up with a better diagnosis and treatment plan.

2. CT Scan

Similar to an MRI, a computed tomography (CT) scan can produce detailed images to help medial professionals assess whether a patient’s symptoms stem from dementia or another condition. By taking a series of x-ray views from different angles, a CT scan allows the doctor to get a three-dimensional look inside the patient’s brain. Most often, a dementia CT scan is used to check for signs of a stroke, a brain tumor, bleeds and other abnormalities.

3. PET Scan

Often used to assess brain functioning, a positron emission tomography (PET) scan is another helpful imaging test for diagnosing dementia. The pictures produced from a PET scan show how the body’s tissues and organs work, which helps a doctor spot any abnormalities in blood flow to the brain. Usually, a PET scan is only ordered if the patient’s initial MRI or CT scan results were inconclusive or uncertain.

It’s important to remember that despite an imaging test showing no obvious changes in the brain, a patient could still have dementia. While imaging technologies have revolutionized the way medical professionals are able to study and examine the brain, studies on how to better track the progress of dementia and Alzheimer’s are ongoing.

Schedule an Imaging Appointment at Health Images

If you or someone you love may need a dementia diagnosing imaging test, schedule an appointment with the caring team at Health Images. At Health Images, our top priorities are excellent patient care and accurate, immediate imaging results. We provide each of our patients with dependable, world-class diagnostic imaging so they can determine the correct treatment path to take.

To book an imaging appointment with a health center you can trust, find a Health Images location near you today.

Schedule an Imaging Appointment at Health Images


  1. https://www.who.int/news-room/fact-sheets/detail/dementia
  2. https://www.alz.org/alzheimers-dementia/what-is-dementia
  3. https://www.alz.org/alzheimers-dementia/what-is-dementia
  4. https://www.healthimages.com/services/mri-scans/
  5. https://www.healthimages.com/the-difference-between-an-mri-and-an-mra/
  6. https://www.healthimages.com/services/ct-scans/
  7. https://www.healthimages.com/ct-scan-vs-pet-scan/#what-is-pet-scan
  8. https://www.healthimages.com/locations/