Cranial magnetic resonance imaging in genetically proven myotonic dystrophy type 1 and 2.

Cranial magnetic resonance imaging (MRI) in 19 German patients with genetically proven myotonic dystrophy Type 1 (DM1, n = 10) or Type 2 (DM2, n = 9) showed pathological findings consisting of white matter lesions (WML) and/or brain atrophy in 9/10 DM1 and 8/9 DM2 patients. Anterior temporal WML (ATWML) were exclusively seen in DM1 patients. Our findings indicate a high frequency of central nervous system (CNS) involvement in both disorders. However, temporopolar pathology, previously associated with intellectual dysfunction, seems to be restricted to DM1.