title: The use of short-echo-time 1H MRS for childhood cerebellar tumours prior to histopathological diagnosis.
abstract: BACKGROUND
  Proton magnetic resonance spectroscopy (MRS) measures concentrations of metabolites in vivo and provides a powerful method for identifying tumours. MRS has not entered routine clinical use partly due to the difficulty of analysing the spectra.
  
  
  OBJECTIVE
  To create a straightforward method for interpreting short-echo-time MRS of childhood cerebellar tumours.
  
  
  METHODS
  Single-voxel MRS (1.5-T Siemens Symphony NUM4, TR/TE 1,500/30 ms) was performed at presentation in 30 children with cerebellar tumours. The MRS results were analysed for comparison with histological diagnosis. Peak heights for N-acetyl aspartate (NAA), creatine (Cr), choline (Cho) and myo-inositol (mIns) were determined and receiver operator characteristic curves used to select ratios that best discriminated between the tumour types. The method was implemented by a group of clinicians and scientists, blinded to the results.
  
  
  RESULTS
  A total of 27 MRS studies met the quality control criteria. NAA/Cr >4.0 distinguished all but one of the astrocytomas from the other tumours. A combination of Cr/Cho <0.75 and mIns/NAA <2.1 separated all the medulloblastomas from the ependymomas.
  
  
  CONCLUSIONS
  Peak height ratios from short-echo-time MRS can accurately predict the histopathology of childhood cerebellar tumours.
authors.affiliation: Academic Department of Paediatrics and Child Health, University of Birmingham, Whittall Street, Birmingham, B4 6NH, UK.
authors.forename: Lisa M
authors.initials: LM
authors.lastname: Harris
authors.forename: Nigel
authors.initials: N
authors.lastname: Davies
authors.forename: Lesley
authors.initials: L
authors.lastname: Macpherson
authors.forename: Katharine
authors.initials: K
authors.lastname: Foster
authors.forename: Shaheen
authors.initials: S
authors.lastname: Lateef
authors.forename: Kal
authors.initials: K
authors.lastname: Natarajan
authors.forename: Spyridon
authors.initials: S
authors.lastname: Sgouros
authors.forename: Marie-Anne
authors.initials: MA
authors.lastname: Brundler
authors.forename: Theodoros N
authors.initials: TN
authors.lastname: Arvanitis
authors.forename: Richard G
authors.initials: RG
authors.lastname: Grundy
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Peet
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D002528:Cerebellar Neoplasms / Q000175:diagnosis* / Q000378:metabolism*; D002531:Cerebellum / Q000378:metabolism; D002648:Child; D002794:Choline / Q000032:analysis*; D003401:Creatine / Q000032:analysis*; D006801:Humans; D007294:Inositol / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D011522:Protons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016037:Single-Blind Method