title: Analysis of T2 signal intensity helps in the differentiation between high and low-grade brain tumours in paediatric patients.
abstract: OBJECTIVE
  Previous studies hypothesized that the analysis of magnetic resonance intensity of the solid portion in paediatric tumours can provide pre-surgical information about the histopathology. Classically, high signal-intensity in T2weighted (T2w) images identifies low-grade tumours, while anaplasia is characterized by T2 hypointensity. We aimed to investigate if T2w signal intensities can pre-operatively distinguish between low-grade and high-grade brain tumours in paediatric patients.
  
  
  METHODS
  Two raters, blinded to the histological diagnosis, rated the signal intensity of MR images (T2w) from 36 children with newly diagnosed brain tumours, 17 children with low-grade brain tumours and 19 children with high-grade brain tumours were included in this study. Relative T2 values were obtained by dividing the T2w values of the solid portion of the tumour by the T2w values of the vitreous humour.
  
  
  RESULTS
  The best cut-off point to distinguish low and high-grade paediatric brain tumours was 0.8. If the signal intensity was less than or equal to 0.8 the tumour was expected to be a high-grade tumour with a sensitivity of 100%. Prediction of a low-grade tumour was more uncertain with a sensitivity of 70.5%. Overall, 86% of the tumours would have been predicted correctly.
  
  
  CONCLUSIONS
  Our data suggest that T2w signal intensities of the solid portion of brain tumours in paediatrics can pre-operatively differentiate between low-grade and high-grade tumours. In addition, T2 hypointensity may be helpful in targeting stereotactic biopsy.
authors.affiliation: Institute of Neuroradiology, Hospital of Goethe University, Frankfurt am Main, Germany. Electronic address: stephanie.lescher@kgu.de.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Lescher
authors.affiliation: Institute of Neuroradiology, Hospital of Goethe University, Frankfurt am Main, Germany.
authors.forename: Ketan
authors.initials: K
authors.lastname: Whora
authors.affiliation: Department of Paediatric Haematology/Oncology, Hospital of Goethe University, Frankfurt am Main, Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Schwabe
authors.affiliation: Department of Neuropaediatric, Hospital of Goethe University, Frankfurt am Main, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Kieslich
authors.affiliation: Institute of Neuroradiology, Hospital of Goethe University, Frankfurt am Main, Germany.
authors.forename: Luciana
authors.initials: L
authors.lastname: Porto
mesh_terms: D000293:Adolescent; D001932:Brain Neoplasms / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D060787:Neoplasm Grading / Q000379:methods; D059906:Neuroimaging / Q000379:methods*; D012680:Sensitivity and Specificity
keywords: Brain Tumours; Children; MRI; T2 Signal intensity