title: Clinical usefulness of CT-myelogram comparing with the MRI in degenerative cervical spinal disorders: is CTM still useful for primary diagnostic tool?
abstract: METHODS
  A radiographic review of 50 patients (29 radiculopathy and 21 myelopathy) who had undergone the anterior cervical discectomy and fusion was performed by 3 observers retrospectively.
  
  
  OBJECTIVE
  To compare the accuracy between magnetic resonance imaging (MRI) and postmyelographic computed tomography (CTM) in degenerative cervical spine disease by assessing the degree of interobserver and intraobserver agreement.
  
  
  BACKGROUND
  The assessment of degenerative cervical spinal disease is still demanding. Now MRI is accepted as a primary diagnostic tool for degenerative cervical spine disease. Compared with MRI, usage of CTM has diminished, but it is usually reserved for the patients for whom MRI results were ambiguous or technically suboptimal.
  
  
  METHODS
  We retrospectively reviewed MRIs and CTMs of 50 patients (29 radiculopathy and 21 myelopathy) who had undergone the anterior cervical discectomy and fusion procedure. Using an assessment scale, 3 observers examined 5 parameters: spinal canal narrowing, foraminal stenosis, bony abnormality, intervertebral disk herniation, and nerve root compression. The degree of severity was graded using a 4-point scale for each item. Intraobserver, interobserver agreement, and the accentuation of each image were analyzed.
  
  
  RESULTS
  Intraclass correlation coefficiency statistical analysis showed moderate intraobserver agreement (Cronbach's alpha=0.63) and interobserver agreement (0.52). There was no significant difference in intraobserver, interobserver agreement between MRI (0.58) and CTM (0.57). Compared between MRI and CTM, disc abnormality and nerve root compression on MRI and foraminal stenosis and bony lesion on CTM showed better agreement.
  
  
  CONCLUSIONS
  CTM was still useful in diagnosis of the foraminal stenosis and bony lesion comparing with MRI but showed limitation in disc abnormality and nerve root compression. So even though CTM may provide valuable additional information in difficult or ambiguous cases, it also requires universal standards and sound experience for constant and objective information.
authors.affiliation: Department of Orthopedic Surgery, School of Medicine, Institute for Medical Science, Chonbuk National University Hospital, Chonbuk National University, Jeonju, Korea.
authors.forename: Kyung-Jin
authors.initials: KJ
authors.lastname: Song
authors.forename: Byung-Wan
authors.initials: BW
authors.lastname: Choi
authors.forename: Gyu-Hyung
authors.initials: GH
authors.lastname: Kim
authors.forename: Jung-Ryul
authors.initials: JR
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000592:standards / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D009192:Myelography / Q000592:standards / Q000706:statistics & numerical data*; D015588:Observer Variation; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D011843:Radiculopathy / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D013117:Spinal Cord Compression / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology; D013123:Spinal Fusion / Q000706:statistics & numerical data; D055009:Spondylosis / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000601:surgery; D014057:Tomography, X-Ray Computed / Q000592:standards / Q000706:statistics & numerical data*; D016896:Treatment Outcome