According to the MS International Federation, there are a range of tests that can be used to find out if someone has MS or not, but there is no single test to diagnose MS which is conclusive on its own.
The most common tests are:
Your neurologist will ask you lots of questions about past symptoms and problems – this is known as ‘history taking’. It helps the neurologist get a better picture of you and can help identify any other problems that may explain current symptoms. A physical examination checks for changes or weaknesses in your eye movements, leg or hand coordination, balance, sensation, speech or reflexes. Whilst a neurologist may strongly suspect MS at this stage, a diagnosis won’t be given until other test results confirm MS.
Magnetic resonance imaging (MRI)
An MRI scanner uses a strong magnetic field to create a detailed image of the brain and spinal cord. It shows the exact location and size of any damage or scarring (lesions). To get the image of the brain and spinal cord, your will lie down and enter a small tunnel in the centre of the MRI scanner. The process can take between 20 and 60 minutes and is painless, but quite noisy.
During a lumbar puncture (or spinal tap), the neurologist inserts a needle into the space around the spinal cord, under local unaesthetic. A small sample of the fluid that flows around the brain and spinal cord, called ‘cerebrospinal fluid’, is taken out and tested for abnormalities that occur in MS. The fluid will be sent to the laboratories to be examined. In some cases the fluid pressure will also be measured. People commonly report headaches following a lumbar puncture. This is a recognized side effect and the neurologist can advise on how best to manage this.