Objective     To study the  magnetic resonance imaging (MRI) in diagnosis of mitochondrial encephalomyopathy (ME).      Methods     Clinical data about 2 ME patients

who were admitted from March 2008 to October 2009 and diagnosed by conventional MRI and magnetic resonance spectroscopy (MRS)

were retrospectively analyzed.      Results       The main clinical manifestations of 1 ME patient with a family history were ataxia and positive muscle biopsy

symmetrical abnormal signals revealed by MRI and double lactate peaks detected by MRS. The main clinical manifestations of the other patient were repeated epilepsy

hearing-impairment

significant family genetic predisposition

and symmetrical abnormal signal foci accompanying brain atrophy revealed by MRI in brain gray and white matter

and increased lactate peak detected by MRS.      Conclusion       MRI can show ME involving the nervous system and MRS contributes to the diagnosis of ME by showing the abnormal lactate peaks.