title: Three-dimensional amide proton transfer MR imaging of gliomas: Initial experience and comparison with gadolinium enhancement.
abstract: OBJECTIVE
  To investigate the feasibility of a three-dimensional amide-proton-transfer (APT) imaging sequence with gradient- and spin-echo readouts at 3 Tesla in patients with high- or low-grade gliomas.
  
  
  METHODS
  Fourteen patients with newly diagnosed gliomas were recruited. After B0 inhomogeneity correction on a voxel-by-voxel basis, APT-weighted images were reconstructed using a magnetization-transfer-ratio asymmetry at offsets of ±3.5 ppm with respect to the water resonance. Analysis of variance post hoc tests were used for statistical evaluations, and results were validated with pathology.
  
  
  RESULTS
  In six patients with gadolinium-enhancing high-grade gliomas, enhancing tumors on the postcontrast T1 -weighted images were consistently hyperintense on the APT-weighted images. Increased APT-weighted signal intensity was also clearly visible in two pathologically proven, high-grade gliomas without gadolinium enhancement. The average APT-weighted signal was significantly higher in the lesions than in the contralateral normal-appearing brain tissue (P < 0.001). In six low-grade gliomas, including two with gadolinium enhancement, APT-weighted imaging showed iso-intensity or mild punctate hyperintensity within all the lesions, which was significantly lower than that seen in the high-grade gliomas (P < 0.001).
  
  
  CONCLUSIONS
  The proposed three-dimensional APT imaging sequence can be incorporated into standard brain MRI protocols for patients with malignant gliomas.
authors: Department of Radiology, Johns Hopkins University, Baltimore, Maryland, USA; F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA.
authors: Jinyuan
authors: J
authors: Zhou
authors: He
authors: H
authors: Zhu
authors: Michael
authors: M
authors: Lim
authors: Lindsay
authors: L
authors: Blair
authors: Alfredo
authors: A
authors: Quinones-Hinojosa
authors: Steven A
authors: SA
authors: Messina
authors: Charles G
authors: CG
authors: Eberhart
authors: Martin G
authors: MG
authors: Pomper
authors: John
authors: J
authors: Laterra
authors: Peter B
authors: PB
authors: Barker
authors: Peter C M
authors: PC
authors: van Zijl
authors: Jaishri O
authors: JO
authors: Blakeley
mesh_terms: D000328:Adult; D000368:Aged; D000465:Algorithms; D000577:Amides; D001932:Brain Neoplasms / Q000473:pathology*; D005240:Feasibility Studies; D005260:Female; D005682:Gadolinium; D005910:Glioma / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011522:Protons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000577:Amides; D011522:Protons; D005682:Gadolinium
keywords: CEST imaging; Key Words: APT imaging; gadolinium enhancement; glioma; tumor grade