TY - RPRT TI - Monitoring disease activity and progression in primary progressive multiple sclerosis using MRI: sub-voxel registration to identify lesion changes and to detect cerebral atrophy. AU - Valerie L Stevenson AU - Stephen M Smith AU - Paul M Matthews AU - David H Miller AU - Alan J Thompson PY - 2002 DO - 10.1007/pl00007860 UR - https://pubmed.ncbi.nlm.nih.gov/11985382/ ID - 11985382 ER -