title: 3D MR sialography protocol for postradiotherapy follow-up of the salivary duct system.
abstract: OBJECTIVE
  To develop and evaluate an MR sialography protocol that reproducibly images the parotid and submandibular ducts over time, in 3D. Such a protocol is needed in order to investigate the possible radiation-induced changes to the salivary ducts in patients receiving radiotherapy to the head-and-neck.
  
  
  METHODS
  MR sialography was performed on a 1.5-T MR scanner. Sequence parameters were optimized on 11 healthy volunteers. A 3D water-selective turbo spin echo (TSE) pulse sequence (TR/TE = 6000 msec/190 msec), using a two-element circular surface coil was applied twice in one MR session. In order to assess the reproducibility, the same procedure was repeated four to six months later. The quality of the MR sialograms was measured subjectively by developing a visibility scoring system and objectively by the means of contrast-to-noise ratio (CNR) of the ducts vs. fat (CNR(duct-fat)).
  
  
  RESULTS
  High-quality, 3D MR sialographic images were obtained. The quality of the MR sialograms and the subjective visibility score of the salivary ducts were constant over time. The CNR(duct-fat) varied between volunteers (standard deviation, SD 26%) but it was relatively constant per volunteer (SD 5%).
  
  
  CONCLUSIONS
  The MR sialography protocol presented in this study provides good quality 3D imaging of the major salivary ducts, submandibular duct, and the parotid duct and it can be used for the comparison of the salivary duct system of an individual over time.
authors.affiliation: Department of Radiation Oncology, University Medical Centre, Utrecht, The Netherlands. E.Astreinidou@umcutrecht.nl
authors.forename: Eleftheria
authors.initials: E
authors.lastname: Astreinidou
authors.forename: Cornelis P J
authors.initials: CP
authors.lastname: Raaymakers
authors.forename: Judith M
authors.initials: JM
authors.lastname: Roesink
authors.forename: Chris H J
authors.initials: CH
authors.lastname: Terhaard
authors.forename: Jan J W
authors.initials: JJ
authors.lastname: Lagendijk
authors.forename: Lambertus W
authors.initials: LW
authors.lastname: Bartels
mesh_terms: D006258:Head and Neck Neoplasms / Q000175:diagnosis / Q000532:radiotherapy; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010306:Parotid Gland / Q000473:pathology; D012468:Salivary Gland Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy*; D012469:Salivary Glands / Q000378:metabolism; D012796:Sialography / Q000379:methods*; D012984:Software; D013363:Submandibular Gland / Q000473:pathology; D014987:Xerostomia / Q000473:pathology