title: Brain MRI findings in patients with idiopathic hypersomnia.
abstract: OBJECTIVE
  Proper diagnosis of idiopathic hypersomnia necessitates the exclusion of neurologic or medical causes of sleepiness that better explain the clinical syndrome. However, there are no formal guidelines regarding the use of neuroimaging to identify such secondary causes of symptoms. We sought to characterize brain MRI findings in a series of patients with idiopathic hypersomnia.
  
  
  METHODS
  We reviewed medical records on a consecutive series of 61 patients diagnosed with idiopathic hypersomnia to determine the frequency and results of brain magnetic resonance imaging (MRI).
  
  
  RESULTS
  One-third of patients had undergone brain MRI, with focal neurologic signs or symptoms being the most common indication for neuroimaging. Although seven patients had an identifiable finding on neuroimaging (e.g., chronic microvascular ischemic changes), clinical management was changed as a result of imaging in only three cases. In all three, the imaging finding was predated by clear clinical abnormalities.
  
  
  CONCLUSIONS
  Neuroimaging may be a complementary part of an idiopathic hypersomnia evaluation, but the decision to pursue imaging should be made on a case-by-case basis.
authors.affiliation: Sleep Center and Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA. Electronic address: Lbecke2@emory.edu.
authors.forename: Lynn Marie
authors.initials: LM
authors.lastname: Trotti
authors.affiliation: Sleep Center and Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA. Electronic address: dbliwis@emory.edu.
authors.forename: Donald L
authors.initials: DL
authors.lastname: Bliwise
mesh_terms: D000328:Adult; D000368:Aged; D001933:Brain Stem / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D020177:Idiopathic Hypersomnia / Q000000981:diagnostic imaging* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009290:Narcolepsy / Q000000981:diagnostic imaging / Q000473:pathology; D059906:Neuroimaging
keywords: Hypersomnolence; Idiopathic hypersomnia; Magnetic resonance imaging; Narcolepsy; Neuroimaging; Sleep disorders