Demyelination and neurodegeneration in grey matter in the brain are critical aspects of the pathology of MS.
Changes in grey matter have been found in early and late disease, with greater changes seen in people with progressive MS.
Grey matter pathology is clearly clinically relevant, as it is associated with cognitive and physical disability.
In recent years, it has become possible to measure changes in grey matter with advances in magnetic resonance imaging (MRI) techniques.
It seems that a very deep region inside the brain, the thalamus, is related to disability in MS. The thalamus is part of the deep grey matter, which is not easily studied by conventional MRI.
A team from the USA recently published the results from a study that aimed to identify and characterize thalamic MS using a high-field MRI scanner. The study involved 34 people with MS and 15 healthy controls.
The researchers found thalamic lesions in more than 70 per cent of those studied. These were greatest in people with progressive MS and in those with more physical disability.
This study supports a link between the development of grey matter disease and a progressive MS phenotype.
According to these results, having a rapid measure of changes in grey matter (such as thalamic lesion burden) would be useful in clinical care and future studies of progressive MS.
Future work should confirm these findings in a larger sample of patients.