Diffusion tensor imaging was used to evaluate cerebral white matter in 16 patients (ages 9-18) with myotonic dystrophy type 1 compared to 15 matched controls. Patients with myotonic dystrophy showed abnormalities in mean diffusivity compared to controls in frontal, temporal, parietal, and occipital white matter and in all individual tracts examined. Whole cerebrum mean diffusivity was 8.6 % higher overall in patients with myotonic dystrophy compared to controls. Whole cerebrum fractional anisotropy was also abnormal (10.8 % low overall) in all regions and tracts except corticospinal tracts. Follow-up analysis of parallel and perpendicular diffusivity suggests possible relative preservation of myelin in corticospinal tracts. Correlations between Wechsler working memory performance and mean diffusivity were strong for all regions. Frontal and temporal fractional anisotropy were correlated with working memory as well. Results are consistent with earlier studies demonstrating that significant white matter disturbances are characteristic in young patients with myotonic dystrophy and that these abnormalities are associated with the degree of working memory impairment seen in this disease.
Bibliographical noteFunding Information:
This work was supported the National Institute of Neurological Disorders and Stroke (NINDS): R01-NS-056592-05; the National Centers for Research Resources: BTRC P41-RR008079 and P4-EB015894; the National Institutes of Health Neuroscience Interdisciplinary Core Center: P30-NS057091 and P30-NS5076408; the Paul and Sheila Wellstone Muscular Dystrophy Center at the University of Minnesota; the University of Minnesota Supercomputing Institute (MSI).
- Diffusion tensor imaging
- Myotonic dystrophy