title: Can we improve accuracy and reliability of MRI interpretation in children with optic pathway glioma? Proposal for a reproducible imaging classification.
abstract: BACKGROUND
  Magnetic resonance (MR) images from children with optic pathway glioma (OPG) are complex. We initiated this study to evaluate the accuracy of MR imaging (MRI) interpretation and to propose a simple and reproducible imaging classification for MRI.
  
  
  METHODS
  We randomly selected 140 MRIs from among 510 MRIs performed on 104 children diagnosed with OPG in France from 1990 to 2004. These images were reviewed independently by three radiologists (F.T., 15 years of experience in neuroradiology; D.L., 25 years of experience in pediatric radiology; and J.L., 3 years of experience in radiology) using a classification derived from the Dodge and modified Dodge classifications. Intra- and interobserver reliabilities were assessed using the Bland-Altman method and the kappa coefficient. These reviews allowed the definition of reliable criteria for MRI interpretation.
  
  
  RESULTS
  The reviews showed intraobserver variability and large discrepancies among the three radiologists (kappa coefficient varying from 0.11 to 1). These variabilities were too large for the interpretation to be considered reproducible over time or among observers. A consensual analysis, taking into account all observed variabilities, allowed the development of a definitive interpretation protocol. Using this revised protocol, we observed consistent intra- and interobserver results (kappa coefficient varying from 0.56 to 1). The mean interobserver difference for the solid portion of the tumor with contrast enhancement was 0.8 cm(3) (limits of agreement = -16 to 17).
  
  
  CONCLUSIONS
  We propose simple and precise rules for improving the accuracy and reliability of MRI interpretation for children with OPG. Further studies will be necessary to investigate the possible prognostic value of this approach.
authors.affiliation: Department of Radiology, University Hospital, 1 Place Alexis-Ricordeau, 44093, Nantes Cedex 1, France. julien.lambron@sfr.fr.
authors.forename: Julien
authors.initials: J
authors.lastname: Lambron
authors.affiliation: Department of Pediatric Oncology, University Hospital, Angers, France.|INSERM CIE5 Robert Debre Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), University Paris Diderot, Paris, France.
authors.forename: Josué
authors.initials: J
authors.lastname: Rakotonjanahary
authors.affiliation: Department of Radiology, University Hospital, Angers, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Loisel
authors.affiliation: Department of Radiology, University Hospital, 1 Place Alexis-Ricordeau, 44093, Nantes Cedex 1, France.
authors.forename: Eric
authors.initials: E
authors.lastname: Frampas
authors.affiliation: Department of Pediatric Oncology, University Hospital, Angers, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: De Carli
authors.affiliation: Department of Neurosurgery, University Hospital, Angers, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Delion
authors.affiliation: Department of Pediatric Oncology, University Hospital, Angers, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Rialland
authors.affiliation: Department of Radiology, University Hospital, 1 Place Alexis-Ricordeau, 44093, Nantes Cedex 1, France.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Toulgoat
mesh_terms: D000465:Algorithms; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D015588:Observer Variation; D020339:Optic Nerve Glioma / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Children; MRI; Optic pathway glioma