Observer performance and diagnostic outcome in diagnosis of the disk position of the temporomandibular joint using arthrography

Observer performance and diagnostic outcome in the diagnosis of the disk position of the temporomandibular joint by arthrography were investigated. Three different radiographic techniques were studied: fluoroscopy, fluoroscopy in combination with lateral transcranial radiography, and fluoroscopy in combination with corrected sagittal tomography. Seven observers were asked to assess 30 joints representing three diagnoses, namely superior disk position and anterior disk position with and without reduction. The intraobserver agreement was high for all three techniques. The interobserver agreement of the seven observers when the disk position was diagnosed by fluoroscopy in combination with lateral transcranial radiography (Kappa index 0.68) was higher than that with fluoroscopy alone (Kappa index 0.54) and that with fluoroscopy in combination with corrected sagittal tomography (Kappa index 0.56). The sensitivity, specificity, and predictive values of fluoroscopy in combination with lateral transcranial radiography were also higher than those of the other radiographic techniques. Judged from this study, the observer agreement and the diagnostic outcome for arthrography with the use of the three examined techniques are high when well-defined criteria and reference images are applied.