title: Multi-modal glioblastoma segmentation: man versus machine.
abstract: OBJECTIVE
  Reproducible segmentation of brain tumors on magnetic resonance images is an important clinical need. This study was designed to evaluate the reliability of a novel fully automated segmentation tool for brain tumor image analysis in comparison to manually defined tumor segmentations.
  
  
  METHODS
  We prospectively evaluated preoperative MR Images from 25 glioblastoma patients. Two independent expert raters performed manual segmentations. Automatic segmentations were performed using the Brain Tumor Image Analysis software (BraTumIA). In order to study the different tumor compartments, the complete tumor volume TV (enhancing part plus non-enhancing part plus necrotic core of the tumor), the TV+ (TV plus edema) and the contrast enhancing tumor volume CETV were identified. We quantified the overlap between manual and automated segmentation by calculation of diameter measurements as well as the Dice coefficients, the positive predictive values, sensitivity, relative volume error and absolute volume error.
  
  
  RESULTS
  Comparison of automated versus manual extraction of 2-dimensional diameter measurements showed no significant difference (p = 0.29). Comparison of automated versus manual segmentation of volumetric segmentations showed significant differences for TV+ and TV (p<0.05) but no significant differences for CETV (p>0.05) with regard to the Dice overlap coefficients. Spearman's rank correlation coefficients (ρ) of TV+, TV and CETV showed highly significant correlations between automatic and manual segmentations. Tumor localization did not influence the accuracy of segmentation.
  
  
  CONCLUSIONS
  In summary, we demonstrated that BraTumIA supports radiologists and clinicians by providing accurate measures of cross-sectional diameter-based tumor extensions. The automated volume measurements were comparable to manual tumor delineation for CETV tumor volumes, and outperformed inter-rater variability for overlap and sensitivity.
authors.affiliation: Support Center for Advanced Neuroimaging - Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland; Department of Neurosurgery, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Nicole
authors.initials: N
authors.lastname: Porz
authors.affiliation: Support Center for Advanced Neuroimaging - Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland; Institute of Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Bauer
authors.affiliation: Department of Radiation Oncology, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Alessia
authors.initials: A
authors.lastname: Pica
authors.affiliation: Department of Neurosurgery, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Philippe
authors.initials: P
authors.lastname: Schucht
authors.affiliation: Department of Neurosurgery, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Beck
authors.affiliation: Support Center for Advanced Neuroimaging - Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Rajeev Kumar
authors.initials: RK
authors.lastname: Verma
authors.affiliation: Support Center for Advanced Neuroimaging - Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Johannes
authors.initials: J
authors.lastname: Slotboom
authors.affiliation: Institute of Surgical Technology and Biomechanics, University of Bern, Bern, Switzerland.
authors.forename: Mauricio
authors.initials: M
authors.lastname: Reyes
authors.affiliation: Support Center for Advanced Neuroimaging - Institute for Diagnostic and Interventional Neuroradiology, University Hospital Inselspital and University of Bern, Bern, Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: Wiest
mesh_terms: D000368:Aged; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D003287:Contrast Media; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010363:Pattern Recognition, Automated; D011859:Radiography; D012984:Software; D047368:Tumor Burden
chemical_list: D003287:Contrast Media