title: Observer variation in the evaluation of lumbar herniated discs and root compression: spiral CT compared with MRI.
abstract: Spiral CT is considered the best alternative for MRI in the evaluation of herniated discs. The purpose of this study was to compare radiological evaluation of spiral CT with MRI in patients suspected of herniated discs. 57 patients with lumbosacral radicular syndrome underwent spiral CT and 1.5 T MRI. Two neuroradiologists independently evaluated 171 intervertebral discs for herniation or "bulge" and 456 nerve roots for root compression, once after CT and once after MRI. We compared interobserver agreement using the kappa statistic and we performed a paired comparison between CT and MRI. For detection of herniated or bulging discs, we observed no significant difference in interobserver agreement (CT kappa 0.66 vs MRI kappa 0.71; p = 0.40). For root compression, we observed significantly better interobserver agreement at MRI evaluation (CT kappa 0.59 vs MRI kappa 0.78; p = 0.01). In 30 of 171 lumbar discs (18%) and in 54 of 456 nerve roots (12%), the observers disagreed on whether CT results were similar to MRI. In the cases without disagreement, CT differed from MRI in 6 discs (3.5%) and in 3 nerve roots (0.7%). For radiological evaluation of lumbar herniated discs, we found no evidence that spiral CT is inferior to MRI. For evaluating lumbar nerve root compression, spiral CT is less reliable than MRI.
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, Academic Medical Center, AZ, Amsterdam.
authors.forename: J C
authors.initials: JC
authors.lastname: van Rijn
authors.forename: N
authors.initials: N
authors.lastname: Klemetso
authors.forename: J B
authors.initials: JB
authors.lastname: Reitsma
authors.forename: P M
authors.initials: PM
authors.lastname: Bossuyt
authors.forename: F J
authors.initials: FJ
authors.lastname: Hulsmans
authors.forename: W C
authors.initials: WC
authors.lastname: Peul
authors.forename: G J
authors.initials: GJ
authors.lastname: den Heeten
authors.forename: J
authors.initials: J
authors.lastname: Stam
authors.forename: C B L M
authors.initials: CB
authors.lastname: Majoie
mesh_terms: D000328:Adult; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000473:pathology; D007405:Intervertebral Disc Displacement / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000000981:diagnostic imaging / Q000473:pathology; D009485:Neuroradiography; D015588:Observer Variation; D011857:Radiographic Image Interpretation, Computer-Assisted; D011871:Radiology; D012680:Sensitivity and Specificity; D013126:Spinal Nerve Roots / Q000000981:diagnostic imaging / Q000473:pathology; D036542:Tomography, Spiral Computed