Functional MRI changes in the central motor system in myotonic dystrophy type 1

Neuroradiologia, I Facoltà di Medicina e Chirurgia, Università di Roma La Sapienza, Viale dell'Università 30, 00185 Rome, Italy.
Magnetic Resonance Imaging (Impact Factor: 2.09). 08/2009; 28(2):226-34. DOI: 10.1016/j.mri.2009.07.006
Source: PubMed


Myotonic dystrophy type 1 (DM1) is a multisystemic disease involving multiple organ systems including central nervous system (CNS) and muscles. Few studies have focused on the central motor system in DM1, pointing to a subclinical abnormality in the CNS. The aim of our study was to investigate patterns of cerebral activation in DM1 during a motor task using functional MRI (fMRI). Fifteen DM1 patients, aged 20 to 59 years, and 15 controls of comparable age were scanned during a self-paced sequential finger-to-thumb opposition task of their dominant right hand. Functional MRI images were analyzed using SPM99. Patients underwent clinical and genetic assessment; all subjects underwent a conventional MR study. Myotonic dystrophy type 1 patients showed greater activation than controls in bilateral sensorimotor areas and inferior parietal lobules, basal ganglia and thalami, in the ipsilateral premotor area, insula and supplementary motor area (corrected P<.05). Analysis of the interaction between disease and age showed that correlation with age was significantly greater in patients than in controls in bilateral sensorimotor areas and in contralateral parietal areas. Other clinical and MR characteristics did not correlate with fMRI. Functional changes in DM1 may represent compensatory mechanisms such as reorganization and redistribution of functional networks to compensate for ultrastructural and neurochemical changes occurring as part of the accelerated aging process.

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Available from: Caterina Mainero, Feb 23, 2015
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    • "In the group comparison, we found reduced fractional anisotropy values along external capsules in patients with myotonic dystrophy types 1 and 2, correlating with the Muscular Impairment Rating Scale score (measuring muscular impairment) in myotonic dystrophy type 1 and motor performance in myotonic dystrophy type 1 and type 2. The external capsule contains corticostriatal projection fibres connecting (pre)frontal and temporal areas with basal ganglia, known to play a major role in motion planning and execution. A recent functional MRI study in myotonic dystrophy type 1 showed activation patterns in central motor system areas that resembled those in healthy older subjects (Caramia et al., 2010). Taken together, these findings give evidence of impaired central motor functioning in myotonic dystrophies, potentially reflecting an accelerated or increased ageing process. "
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