It can be difficult to diagnose progressive supranuclear palsy (PSP), as there’s no single test for it, and the condition can have similar symptoms to a number of others.
There are also many possible symptoms of PSP and several different sub-types that vary slightly, making it hard to make a definitive diagnosis in the early stages of the condition.
A diagnosis of PSP will be based on the pattern of your symptoms and by ruling out conditions that can cause similar symptoms, such as Parkinson's disease or a stroke.
Your doctor will need to carry out assessments of your symptoms, plus other tests and scans.
The diagnosis must be made or confirmed by a consultant with expertise in PSP. This will usually be a neurologist (specialist in conditions affecting the brain and nerves).
If you have symptoms of PSP that suggest there's something wrong with your brain, it's likely you'll be referred for a brain scan.
Types of scan that you may have include:
- magnetic resonance imaging (MRI) scan – where a strong magnetic field and radio waves are used to produce detailed images of the inside of the brain
- positive emission tomography (PET) scan – a scan that detects the radiation given off by a substance injected beforehand
- a DaTscan – where you're given an injection containing a small amount of a radioactive material and pictures of your brain are taken with a gamma camera
These scans can be useful in ruling out other possible conditions, such as brain tumours or strokes.
MRI scans can also detect abnormal changes to the brain that are consistent with a diagnosis of PSP, such as shrinkage of certain areas.
Scans that show the build-up of the tau protein in the brain that's associated with PSP are currently under development.
Ruling out Parkinson’s disease
You may be prescribed a short course of a medication called levodopa to determine whether your symptoms are caused by PSP or Parkinson's disease.
People with Parkinson's disease usually experience a significant improvement in their symptoms after taking levodopa, whereas the medication only has a limited beneficial effect for some people with PSP.
It's also likely you'll be referred to a neurologist and possibly also a psychologist for neuropsychological testing.
This involves having a series of tests that are designed to evaluate the full extent of your symptoms and their impact on your mental abilities.
The tests will look at abilities such as:
- understanding language
- the processing of visual information, such as words and pictures
Most people with PSP have a distinct pattern in terms of their mental abilities, including poor concentration, a low attention span and problems with spoken language and processing visual information. Their memory of previously learned facts isn't usually significantly affected.
Coping with a diagnosis
Being told that you have PSP can be devastating and difficult to take in.
You may feel numb, overwhelmed, angry, distressed, scared or in denial. Some people are relieved that a cause for their symptoms has finally been found. There's no right or wrong way to feel – everybody is different and copes in their own way.
Support from your family and care team can help you come to terms with the diagnosis.
The PSP Association can give you information and practical advice about living with PSP, as well as providing support to help you cope with the emotional impact of the condition.
You can get in touch with the PSP Association by calling their helpline on 0300 0110 122, or by emailing: email@example.com.