OBJECTIVE: To determine the functional and structural substrates of motor network dysfunction in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: Using a 3-T scanner, in 12 right-handed RRMS patients and 14 matched controls, we acquired diffusion tensor (DT) MRI and functional MRI during the performance of a simple motor task with the right (R) hand. Using DT MRI tractography, we calculated DT-derived metrics from several motor and nonmotor white matter (WM) fiber bundles. Functional connectivity analysis was performed using SPM2. RESULTS: Compared with control, MS patients had abnormal DT MRI metrics of all the WM bundles studied. Compared with controls, MS patients had more significant activations of the left (L) supplementary motor area (SMA), the L primary sensorimotor cortex (SMC), and the R cerebellum. They also had increased functional connectivity between the R primary SMC and the R cerebellum (p = 0.01) and the L SMA and the L primary SMC (p = 0.04). Coefficients of altered connectivity were correlated with structural MRI metrics of tissue damage of the corticospinal and the dentatorubrothalamic tract (r values ranging from -0.73 to 0.85). CONCLUSIONS: The correlations found between measures of functional connectivity and structural damage to some of the major brain motor white matter bundles suggest an adaptive role of functional connectivity changes in limiting the clinical consequences of structural damage in patients with relapsing-remitting multiple sclerosis. Combining measures of altered functional and structural connectivities of specific brain networks is a promising tool to elucidate the mechanisms responsible for clinical manifestations of CNS damage.
OBJECTIVE: To determine the functional and structural substrates of motor network dysfunction in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: Using a 3-T scanner, in 12 right-handed RRMS patients and 14 matched controls, we acquired diffusion tensor (DT) MRI and functional MRI during the performance of a simple motor task with the right (R) hand. Using DT MRI tractography, we calculated DT-derived metrics from several motor and nonmotor white matter (WM) fiber bundles. Functional connectivity analysis was performed using SPM2. RESULTS: Compared with control, MSpatients had abnormal DT MRI metrics of all the WM bundles studied. Compared with controls, MSpatients had more significant activations of the left (L) supplementary motor area (SMA), the L primary sensorimotor cortex (SMC), and the R cerebellum. They also had increased functional connectivity between the R primary SMC and the R cerebellum (p = 0.01) and the L SMA and the L primary SMC (p = 0.04). Coefficients of altered connectivity were correlated with structural MRI metrics of tissue damage of the corticospinal and the dentatorubrothalamic tract (r values ranging from -0.73 to 0.85). CONCLUSIONS: The correlations found between measures of functional connectivity and structural damage to some of the major brain motor white matter bundles suggest an adaptive role of functional connectivity changes in limiting the clinical consequences of structural damage in patients with relapsing-remitting multiple sclerosis. Combining measures of altered functional and structural connectivities of specific brain networks is a promising tool to elucidate the mechanisms responsible for clinical manifestations of CNS damage.
Authors: K Kacar; M A Rocca; M Copetti; S Sala; S Mesaros; T Stosic Opincal; D Caputo; M Absinta; J Drulovic; V S Kostic; G Comi; M Filippi Journal: AJNR Am J Neuroradiol Date: 2011-11-11 Impact factor: 3.825
Authors: M A Rocca; G Riccitelli; M Rodegher; A Ceccarelli; A Falini; M Falautano; A Meani; G Comi; Massimo Filippi Journal: AJNR Am J Neuroradiol Date: 2010-03-18 Impact factor: 3.825
Authors: Rohit Bakshi; Alan J Thompson; Maria A Rocca; Daniel Pelletier; Vincent Dousset; Frederik Barkhof; Matilde Inglese; Charles R G Guttmann; Mark A Horsfield; Massimo Filippi Journal: Lancet Neurol Date: 2008-07 Impact factor: 44.182
Authors: Colleen A Hanlon; Michael J Wesley; Alicia J Roth; Mack D Miller; Linda J Porrino Journal: Psychiatry Res Date: 2010-01-30 Impact factor: 3.222