title: Improved accuracy of diagnosis of lumbar intra and/or extra-foraminal stenosis by use of three-dimensional MR imaging: comparison with conventional MR imaging.
abstract: BACKGROUND
  The purposes of this study were to assess the reliability of 3-dimensional magnetic resonance (MR) imaging (3D MRI) and conventional MRI (CMRI) for detection of lumbar intra and/or extra-foraminal stenosis (LIEFS) and to compare the diagnostic accuracy of the 2 imaging modalities.
  
  
  METHODS
  A total of 60 sets of 3D MR and CMR images from 20 healthy volunteers and 40 LIEFS patients were qualitatively rated according to defined criteria by 3 independent, blinded readers. Kappa statistics were used to characterize intra and inter-reader reliability for qualitative rating of data. Multireader, multicase analysis was used to compare lumbar foraminal stenosis detection between the 2 modalities.
  
  
  RESULTS
  Intra-reader agreement for 3D MRI was excellent, with kappa = 0.90; that for CMRI was good, with kappa = 0.78. Average inter-reader agreement for 3D MRI was good, with kappa = 0.79, whereas that for CMRI was moderate, with kappa = 0.41. Average area under the ROC curve values (1st reading/2nd reading) for detection of lumbar foraminal stenosis using 3D MRI and CMRI were 0.99/0.99 and 0.94/0.92, respectively. Detection of LIEFS with 3D MRI was significantly better than with CMRI (P = 0.0408/0.0294).
  
  
  CONCLUSIONS
  These results suggest that CMRI was of limited use for detection of the presence of LIEFS. Isolated imaging with CMRI may risk overlooking the presence of LIEFS. In contrast, reliability of 3D MRI for detection of LIEFS was good. Furthermore, readers' performance in the diagnosis of LIEFS can be improved by use of 3D MRI. Therefore, 3D MRI is recommended when using imaging for diagnosis of LIEFS.
authors.affiliation: Department of Orthopedic Surgery, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama, 641-8510, Japan, yamacha@wakayama-med.ac.jp.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamada
authors.forename: Masaki
authors.initials: M
authors.lastname: Terada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Iwasaki
authors.forename: Toru
authors.initials: T
authors.lastname: Endo
authors.forename: Motohiro
authors.initials: M
authors.lastname: Okada
authors.forename: Shinichi
authors.initials: S
authors.lastname: Nakao
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hashizume
authors.forename: Akihito
authors.initials: A
authors.lastname: Minamide
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: Hideto
authors.initials: H
authors.lastname: Nishi
authors.forename: Syunji
authors.initials: S
authors.lastname: Tsutsui
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Oka
authors.forename: Munehito
authors.initials: M
authors.lastname: Yoshida
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013130:Spinal Stenosis / Q000175:diagnosis*