title: A comparative study of the diagnostic capabilities of 2D plain radiograph and 3D cone beam CT sialography.
abstract: OBJECTIVE
  The aim of this study was to compare the diagnostic capabilities of two-dimensional sialography with a novel three-dimensional technique using cone beam CT (CBCT).
  
  
  METHODS
  47 subjects underwent parotid or submandibular gland sialography over a 2 year period using both plain imaging and CBCT. Both image sets were anonymized and independently reviewed by three certified oral and maxillofacial radiologists blinded to the clinical data. McNemar's χ(2) test was used to determine differences between the two modalities for feature visualization and interpretation.
  
  
  RESULTS
  CBCT outperformed plain imaging with respect to visualization of the gland parenchyma (p < 0.001) and identification of sialoliths (p = 0.02). Plain imaging outperformed CBCT for the identification of strictures (p = 0.04); however, the negative per cent agreement ("specificity") between the two imaging modalities was 100%. Although both imaging modalities performed equally in identifying normal and abnormal sialographic examinations, CBCT demonstrated a high negative per cent agreement for normal glands and a high positive per cent agreement ("sensitivity") for abnormal glands with inflammatory changes.
  
  
  CONCLUSIONS
  CBCT sialography allowed better visualization of gland parenchyma and identification of sialoliths. The high negative per cent agreement for strictures suggests that, if strictures are identified on CBCT images, then obstruction can be ruled in. Relative to plain images, the high negative per cent agreement for normal glands suggests that, if an abnormal finding is detected on CBCT images, then disease can be ruled in, and the high positive per cent agreement for glands with inflammatory changes suggests that inflammation can be ruled out if these changes are not seen on CBCT images.
authors.affiliation: Faculty of Dentistry, the University of Toronto, Toronto, ON, Canada. fatimajadu@hotmail.com
authors.forename: F M
authors.initials: FM
authors.lastname: Jadu
authors.forename: E W N
authors.initials: EW
authors.lastname: Lam
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000000981:diagnostic imaging; D011446:Prospective Studies; D015494:Salivary Gland Calculi / Q000175:diagnosis / Q000000981:diagnostic imaging; D012466:Salivary Gland Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging*; D012796:Sialography / Q000379:methods*; D013363:Submandibular Gland / Q000000981:diagnostic imaging; D055815:Young Adult