The authors describe a girl with Costello syndrome who showed cerebral palsy and neurosensorial deafness. Brain computer tomography and magnetic resonance findings were normal. Multivoxel proton magnetic resonance spectroscopy showed a lowering of the peak of choline with a reduced choline/creatine ratio at the level of the centrum semiovale. These findings might be due to a congenital dysmyelinating or hypomyelinating condition. A complete neuroimaging study can play a relevant role to better clarify the pathogenesis of brain involvement in Costello syndrome.