Mechanisms of disability and recovery in MS

Professor Alan Thompson and Professor David Miller

We have focused on optic neuritis as it provides special opportunities to understand the mechanisms of symptom development and recovery.

Serial MRI studies of the optic nerve have revealed characteristic time-linked changes in the magnetisation transfer ratio (MTR) and cross-sectional area of the optic nerve. Diffusion tractography has shown abnormalities in the optic radiation that may reflect trans-synaptic degeneration. Abnormal fMRI responses also occur after optic neuritis and simultaneous correlation with structural optic nerve MR measures and visual function suggests that these alterations are adaptive in the acute phase of visual loss.

The next phase of the work will include the development of diffusion tractography at higher fields to improve monitoring of white matter tract damage and retinal nerve fibre layer imaging to investigate the relationship between axonal loss, functional effects and MRI in optic neuritis (in collaboration with Mr Ted Garway-Heath, Moorfields Eye Hospital). In addition, we will study the mechanisms of damage in acute lesions that occur in the motor tracts in the brain and cervical spinal cord of MS patients, and, in particular, assess the impact of lesions on the axons which traverse them (Dr Olga Ciccarelli in collaboration with Professor Paul Matthews, Centre for Functional Magnetic Resonance Imaging of the Brain, John Radcliffe Hospital, Oxford)