title: Whole Body Magnetic Resonance Imaging Features in Diffuse Idiopathic Skeletal Hyperostosis in Conjunction with Clinical Variables to Whole Body MRI and Clinical Variables in Ankylosing Spondylitis.
abstract: OBJECTIVE
  Discrimination of diffuse idiopathic skeletal hyperostosis (DISH) and ankylosing spondylitis (AS) can be challenging. Usefulness of whole-body magnetic resonance imaging (WB-MRI) in diagnosing spondyloarthritis has been recently proved. We assessed the value of clinical variables alone and in combination with WB-MRI to distinguish between DISH and AS.
  
  
  METHODS
  Diagnostic case-control study: 33 patients with AS and 15 patients with DISH were included. All patients underwent 1.5 Tesla WB-MRI scanning. MR scans were read by a blinded radiologist using the Canadian-Danish Working Group's recommendation. Imaging and clinical variables were identified using the bootstrap. The most important variables from MR and clinical history were assessed in a multivariate fashion resulting in 3 diagnostic models (MRI, clinical, and combined). The discriminative capacity was quantified using the area under the receiver-operating characteristic (ROC) curve. The strength of diagnostic variables was quantified with OR.
  
  
  RESULTS
  Forty-eight patients provided 1545 positive findings (193 DISH/1352 AS). The final MR model contained upper anterior corner fat infiltration (32 DISH/181 AS), ankylosis on the vertebral endplate (4 DISH/60 AS), facet joint ankylosis (4 DISH/49 AS), sacroiliac joint edema (11 DISH/91 AS), sacroiliac joint fat infiltration (2 DISH/114 AS), sacroiliac joint ankylosis (2 DISH/119 AS); area under the ROC curve was 0.71, 95% CI 0.64-0.78. The final clinical model contained patient's age and body mass index (area under the ROC curve 0.90, 95% CI 0.89-0.91). The full diagnostic model containing clinical and MR information had an area under the ROC curve of 0.93 (95% CI 0.92-0.95).
  
  
  CONCLUSIONS
  WB-MRI features can contribute to the correct diagnosis after a thorough conventional workup of patients with DISH and AS.
authors.affiliation: From the Department of Physical Medicine and Rheumatology, and Department of Radiology, Balgrist University Hospital; Medignition Inc. Research Consultants, Zurich, Switzerland.B.G. Weiss, MD, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; L.M. Bachmann, MD, PhD, Professor, Medignition Inc. Research Consultants; C.W. Pfirrmann, MD, exec. MBA UZH, Department of Radiology, Balgrist University Hospital; R.O. Kissling, MD, Professor, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; V. Zubler, MD, Department of Radiology, Balgrist University Hospital. bettina.weiss@balgrist.ch.
authors.forename: Bettina G
authors.initials: BG
authors.lastname: Weiss
authors.affiliation: From the Department of Physical Medicine and Rheumatology, and Department of Radiology, Balgrist University Hospital; Medignition Inc. Research Consultants, Zurich, Switzerland.B.G. Weiss, MD, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; L.M. Bachmann, MD, PhD, Professor, Medignition Inc. Research Consultants; C.W. Pfirrmann, MD, exec. MBA UZH, Department of Radiology, Balgrist University Hospital; R.O. Kissling, MD, Professor, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; V. Zubler, MD, Department of Radiology, Balgrist University Hospital.
authors.forename: Lucas M
authors.initials: LM
authors.lastname: Bachmann
authors.affiliation: From the Department of Physical Medicine and Rheumatology, and Department of Radiology, Balgrist University Hospital; Medignition Inc. Research Consultants, Zurich, Switzerland.B.G. Weiss, MD, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; L.M. Bachmann, MD, PhD, Professor, Medignition Inc. Research Consultants; C.W. Pfirrmann, MD, exec. MBA UZH, Department of Radiology, Balgrist University Hospital; R.O. Kissling, MD, Professor, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; V. Zubler, MD, Department of Radiology, Balgrist University Hospital.
authors.forename: Christian W A
authors.initials: CW
authors.lastname: Pfirrmann
authors.affiliation: From the Department of Physical Medicine and Rheumatology, and Department of Radiology, Balgrist University Hospital; Medignition Inc. Research Consultants, Zurich, Switzerland.B.G. Weiss, MD, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; L.M. Bachmann, MD, PhD, Professor, Medignition Inc. Research Consultants; C.W. Pfirrmann, MD, exec. MBA UZH, Department of Radiology, Balgrist University Hospital; R.O. Kissling, MD, Professor, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; V. Zubler, MD, Department of Radiology, Balgrist University Hospital.
authors.forename: Rudolf O
authors.initials: RO
authors.lastname: Kissling
authors.affiliation: From the Department of Physical Medicine and Rheumatology, and Department of Radiology, Balgrist University Hospital; Medignition Inc. Research Consultants, Zurich, Switzerland.B.G. Weiss, MD, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; L.M. Bachmann, MD, PhD, Professor, Medignition Inc. Research Consultants; C.W. Pfirrmann, MD, exec. MBA UZH, Department of Radiology, Balgrist University Hospital; R.O. Kissling, MD, Professor, Department of Physical Medicine and Rheumatology, Balgrist University Hospital; V. Zubler, MD, Department of Radiology, Balgrist University Hospital.
authors.forename: Veronika
authors.initials: V
authors.lastname: Zubler
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D004057:Hyperostosis, Diffuse Idiopathic Skeletal / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010388:Pelvis / Q000000981:diagnostic imaging / Q000473:pathology*; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology*; D013167:Spondylitis, Ankylosing / Q000000981:diagnostic imaging / Q000473:pathology*; D051598:Whole Body Imaging
keywords: ANKYLOSING SPONDYLITIS; CASE-CONTROL STUDIES; DIFFUSE IDIOPATHIC SKELETAL HYPEROSTOSIS; MAGNETIC RESONANCE IMAGING; SPONDYLOARTHROPATHY