title: Brain tumor classification using the diffusion tensor image segmentation (D-SEG) technique.
abstract: BACKGROUND
  There is an increasing demand for noninvasive brain tumor biomarkers to guide surgery and subsequent oncotherapy. We present a novel whole-brain diffusion tensor imaging (DTI) segmentation (D-SEG) to delineate tumor volumes of interest (VOIs) for subsequent classification of tumor type. D-SEG uses isotropic (p) and anisotropic (q) components of the diffusion tensor to segment regions with similar diffusion characteristics.
  
  
  METHODS
  DTI scans were acquired from 95 patients with low- and high-grade glioma, metastases, and meningioma and from 29 healthy subjects. D-SEG uses k-means clustering of the 2D (p,q) space to generate segments with different isotropic and anisotropic diffusion characteristics.
  
  
  RESULTS
  Our results are visualized using a novel RGB color scheme incorporating p, q and T2-weighted information within each segment. The volumetric contribution of each segment to gray matter, white matter, and cerebrospinal fluid spaces was used to generate healthy tissue D-SEG spectra. Tumor VOIs were extracted using a semiautomated flood-filling technique and D-SEG spectra were computed within the VOI. Classification of tumor type using D-SEG spectra was performed using support vector machines. D-SEG was computationally fast and stable and delineated regions of healthy tissue from tumor and edema. D-SEG spectra were consistent for each tumor type, with constituent diffusion characteristics potentially reflecting regional differences in tissue microstructure. Support vector machines classified tumor type with an overall accuracy of 94.7%, providing better classification than previously reported.
  
  
  CONCLUSIONS
  D-SEG presents a user-friendly, semiautomated biomarker that may provide a valuable adjunct in noninvasive brain tumor diagnosis and treatment planning.
authors.affiliation: Academic Neurosurgery Unit, St. Georges, University of London, London, UK (T.L.J., T.J.B., B.A.B.); Neurosciences Research Centre, Cardio-vascular and Cell Sciences Institute, St. George's, University of London, London, UK (G.Y., F.A.H., T.R.B.).
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Jones
authors.affiliation: Academic Neurosurgery Unit, St. Georges, University of London, London, UK (T.L.J., T.J.B., B.A.B.); Neurosciences Research Centre, Cardio-vascular and Cell Sciences Institute, St. George's, University of London, London, UK (G.Y., F.A.H., T.R.B.).
authors.forename: Tiernan J
authors.initials: TJ
authors.lastname: Byrnes
authors.affiliation: Academic Neurosurgery Unit, St. Georges, University of London, London, UK (T.L.J., T.J.B., B.A.B.); Neurosciences Research Centre, Cardio-vascular and Cell Sciences Institute, St. George's, University of London, London, UK (G.Y., F.A.H., T.R.B.).
authors.forename: Guang
authors.initials: G
authors.lastname: Yang
authors.affiliation: Academic Neurosurgery Unit, St. Georges, University of London, London, UK (T.L.J., T.J.B., B.A.B.); Neurosciences Research Centre, Cardio-vascular and Cell Sciences Institute, St. George's, University of London, London, UK (G.Y., F.A.H., T.R.B.).
authors.forename: Franklyn A
authors.initials: FA
authors.lastname: Howe
authors.affiliation: Academic Neurosurgery Unit, St. Georges, University of London, London, UK (T.L.J., T.J.B., B.A.B.); Neurosciences Research Centre, Cardio-vascular and Cell Sciences Institute, St. George's, University of London, London, UK (G.Y., F.A.H., T.R.B.).
authors.forename: B Anthony
authors.initials: BA
authors.lastname: Bell
authors.affiliation: Academic Neurosurgery Unit, St. Georges, University of London, London, UK (T.L.J., T.J.B., B.A.B.); Neurosciences Research Centre, Cardio-vascular and Cell Sciences Institute, St. George's, University of London, London, UK (G.Y., F.A.H., T.R.B.).
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Barrick
mesh_terms: D000465:Algorithms; D015415:Biomarkers; D001929:Brain Edema / Q000473:pathology; D001932:Brain Neoplasms / Q000145:classification* / Q000473:pathology*; D056324:Diffusion Tensor Imaging / Q000379:methods*; D005260:Female; D005910:Glioma / Q000145:classification / Q000473:pathology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008297:Male; D008577:Meningeal Neoplasms / Q000145:classification / Q000473:pathology; D008579:Meningioma / Q000145:classification / Q000473:pathology; D008875:Middle Aged
chemical_list: D015415:Biomarkers
keywords: biomarker; brain tumor; diffusion tensor imaging; glioblastoma; segmentation