title: Differentiation of Low- and High-Grade Pediatric Brain Tumors with High b-Value Diffusion-weighted MR Imaging and a Fractional Order Calculus Model.
abstract: OBJECTIVE
  To demonstrate that a new set of parameters (D, β, and μ) from a fractional order calculus (FROC) diffusion model can be used to improve the accuracy of MR imaging for differentiating among low- and high-grade pediatric brain tumors.
  
  
  METHODS
  The institutional review board of the performing hospital approved this study, and written informed consent was obtained from the legal guardians of pediatric patients. Multi-b-value diffusion-weighted magnetic resonance (MR) imaging was performed in 67 pediatric patients with brain tumors. Diffusion coefficient D, fractional order parameter β (which correlates with tissue heterogeneity), and a microstructural quantity μ were calculated by fitting the multi-b-value diffusion-weighted images to an FROC model. D, β, and μ values were measured in solid tumor regions, as well as in normal-appearing gray matter as a control. These values were compared between the low- and high-grade tumor groups by using the Mann-Whitney U test. The performance of FROC parameters for differentiating among patient groups was evaluated with receiver operating characteristic (ROC) analysis.
  
  
  RESULTS
  None of the FROC parameters exhibited significant differences in normal-appearing gray matter (P ≥ .24), but all showed a significant difference (P < .002) between low- (D, 1.53 μm(2)/msec ± 0.47; β, 0.87 ± 0.06; μ, 8.67 μm ± 0.95) and high-grade (D, 0.86 μm(2)/msec ± 0.23; β, 0.73 ± 0.06; μ, 7.8 μm ± 0.70) brain tumor groups. The combination of D and β produced the largest area under the ROC curve (0.962) in the ROC analysis compared with individual parameters (β, 0.943; D,0.910; and μ, 0.763), indicating an improved performance for tumor differentiation.
  
  
  CONCLUSIONS
  The FROC parameters can be used to differentiate between low- and high-grade pediatric brain tumor groups. The combination of FROC parameters or individual parameters may serve as in vivo, noninvasive, and quantitative imaging markers for classifying pediatric brain tumors.
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: Yi
authors.initials: Y
authors.lastname: Sui
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: He
authors.initials: H
authors.lastname: Wang
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: Guanzhong
authors.initials: G
authors.lastname: Liu
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Damen
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: Christian
authors.initials: C
authors.lastname: Wanamaker
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Li
authors.affiliation: From the Center for MR Research (Y.S., G.L., F.W.D., X.J.Z.) and Departments of Radiology (C.W., X.J.Z.), Neurosurgery (X.J.Z.), and Bioengineering (Y.S., X.J.Z.), University of Illinois Hospital & Health Sciences System, 1801 W Taylor St, MC-707, Suite 1A, Chicago, IL 60612; Applied Science Laboratory, GE Healthcare, Shanghai, China (H.W.); and Department of Radiology, Xinhua Hospital, Shanghai, China (Y.L.).
authors.forename: Xiaohong Joe
authors.initials: XJ
authors.lastname: Zhou
mesh_terms: D000293:Adolescent; D001932:Brain Neoplasms / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D007223:Infant; D008297:Male; D060787:Neoplasm Grading; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media