Could MRI scans replace lumbar punctures in MS diagnosis?

Many people with MS will have a lumbar puncture (also called a spinal tap) as part of their diagnosis. This is where a thin needle is inserted into the lower back, to collect cerebrospinal fluid. It can be painful and invasive, and some people experience severe side effects.

In 2010, we funded researchers at the University of Nottingham to investigate a MRI technique called T2*. Despite the similarity in name, T2* is not the same as T2 scans (which are already commonly used to spot lesions in MS).

The researchers used T2* scans to detect the ‘central vein sign’ (CVS). This is where lesions (areas of damage in the brain) have a vein in their centre. They found that this could be used to tell MS apart from other conditions.

But until recently, the T2* scans were only possible with the most powerful MRIs used in research. But the researchers have now optimised the technique to work on standard hospital scanners. This means the technique could potentially be used to diagnose MS.

What did the researchers do?

Building on their previous research, they compared lumbar punctures with of CVS detected by T2* MRI scans.

People with suspected MS had both an T2* MRI scan to detect CVS and a lumbar puncture. Researchers compared how sensitive (able to correctly identify people with MS) and specific (able to correctly identify people without MS) the two diagnosis methods were.

What did they find?

Researchers found that the sensitivity of the CVS from the T2* scans was comparable to lumbar punctures. This meant that the CVS was able to detect correctly which people had MS. People experienced more side effects after a lumbar puncture. And preferred the MRI scan.

The CVS from the T2* scans wasn’t as specific as the lumbar puncture. This meant that it could potentially lead to a diagnosis of MS in people who don’t have the condition. Further research is needed to understand this.

What does this mean for people with MS?

Some people with suspected MS will still need to have a lumbar puncture. So this research won’t mean that lumbar punctures are replaced entirely. But it could reduce the number of people who need a lumbar puncture to diagnose their MS.

In September 2024 at the ECTRIMS conference a panel of MS experts shared an insight into what changes to the diagnostic criteria they recommended. These are now being reviewed by other neurologists before they can become official.

The proposed changes to the McDonald criteria, resulting from this and other research, say that a positive lumbar puncture or finding 6 lesions with a CVS from T2* scans (the technique they looked at in this study) can confirm a diagnosis of MS.