Abstract #3244

Relating Thalamic Atrophy and White Matter Lesions at the Earliest Stages of Multiple Sclerosis

Bagrat Amirbekian¹, Mason Shieh¹, SungWon Chung¹, Darin T. Okuda², Daniel Pelletier², Roland G. Henry^1,3

¹Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA; ²Neurology, University of California, San Francisco, CA, USA; ³Graduate Group in Bioengineering, University of California, Berkeley & San Francisco, CA, USA

A previous VBM study has shown thalamic atrophy significantly correlated with white matter lesion volume in CIS patients at presentation. One possibility is that WM lesions and thalamic atrophy are both due to a common disease mechanism and therefore do not have a causative relation. Alternatively, the white matter lesions may cause the thalamic atrophy and/or thalamic degeneration may be in part responsible for pathology arising in connected axonal bundles. In order to shed further light on these possibilities, we have investigated this relationship using diffusion tensor MRI fiber tractography to delineate the white matter pathways connected to the thalamus.