title: Recurrent glioblastoma multiforme versus radiation injury: a multiparametric 3-T MR approach.
abstract: OBJECTIVE
  The discrimination between recurrent glioma and radiation injury is often a challenge on conventional magnetic resonance imaging (MRI). We verified whether adding and combining proton MR spectroscopic imaging ((1)H-MRSI), diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) information at 3 Tesla facilitate such discrimination.
  
  
  METHODS
  Twenty-nine patients with histologically verified high-grade gliomas, who had undergone surgical resection and radiotherapy, and had developed new contrast-enhancing lesions close to the treated tumour, underwent MRI, (1)H-MRSI, DWI and PWI at regular time intervals. The metabolite ratios choline (Cho)/normal( n )Cho n , N-acetylaspartate (NAA)/NAA n , creatine (Cr)/Cr n , lactate/lipids (LL)/LL n , Cho/Cr n , NAA/Cr n , Cho/NAA, NAA/Cr and Cho/Cr were derived from (1)H-MRSI; the apparent diffusion coefficient (ADC) from DWI; and the relative cerebral blood volume (rCBV) from PWI.
  
  
  RESULTS
  In serial MRI, recurrent gliomas showed a progressive enlargement, and radiation injuries showed regression or no modification. Discriminant analysis showed that discrimination accuracy was 79.3 % when considering only the metabolite ratios (predictor, Cho/Cr n ), 86.2 % when considering ratios and ADC (predictors, Cho/Cr n and ADC), 89.7 % when considering ratios and rCBV (predictors, Cho/Cr n , Cho/Cr and rCBV), and 96.6 % when considering ratios, ADC and rCBV (predictors, Cho/Cho n , ADC and rCBV).
  
  
  CONCLUSIONS
  The multiparametric 3-T MR assessment based on (1)H-MRSI, DWI and PWI in addition to MRI is a useful tool to discriminate tumour recurrence/progression from radiation effects.
authors.affiliation: Dipartimento di Medicina e Scienze per la Salute, Università del Molise, Via De Sanctis snc, 86100, Campobasso, Italy, alfonso.dicostanzo@unimol.it.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Di Costanzo
authors.forename: Tommaso
authors.initials: T
authors.lastname: Scarabino
authors.forename: Francesca
authors.initials: F
authors.lastname: Trojsi
authors.forename: Teresa
authors.initials: T
authors.lastname: Popolizio
authors.forename: Simona
authors.initials: S
authors.lastname: Bonavita
authors.forename: Mario
authors.initials: M
authors.lastname: de Cristofaro
authors.forename: Renata
authors.initials: R
authors.lastname: Conforti
authors.forename: Adriana
authors.initials: A
authors.lastname: Cristofano
authors.forename: Claudio
authors.initials: C
authors.lastname: Colonnese
authors.forename: Ugo
authors.initials: U
authors.lastname: Salvolini
authors.forename: Gioacchino
authors.initials: G
authors.lastname: Tedeschi
mesh_terms: D000328:Adult; D000368:Aged; D001930:Brain Injuries / Q000175:diagnosis*; D001932:Brain Neoplasms / Q000175:diagnosis*; D003937:Diagnosis, Differential; D005260:Female; D005909:Glioblastoma / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis*; D011832:Radiation Injuries / Q000175:diagnosis*