title: Salivary gland function evaluated by diffusion-weighted MR imaging with gustatory stimulation: preliminary results.
abstract: OBJECTIVE
  To evaluate the usefulness of diffusion-weighted MR imaging using a transient gustatory stimulation method in patients with xerostomia.
  
  
  METHODS
  Ten consecutive patients complaining of xerostomia and 10 healthy volunteers were examined with a 1.5 Tesla (T) MR unit. All study subjects completed a questionnaire, and patients underwent salivary gland scintigraphy and Saxon test. T1-, T2-, and diffusion-weighted MR images were obtained before stimulation. One minute after gustatory stimulation with lemon juice, diffusion-weighted sequence was repeated 9 times. A radiologist evaluated signal intensities and apparent diffusion coefficients (ADCs) in parotid and submandibular glands. ADC increase rate (IR) and times to maximum ADC (Tmax) were assessed.
  
  
  RESULTS
  IRs showed a moderate positive correlation with washout rates by scintigraphy for parotid (r = 0.554, P < 0.05) and submandibular (r = 0.617, P < 0.01) glands. Furthermore, Tmax values of parotid and submandibular glands were significantly higher in patients (420 ± 226 and 357 ± 232 s, respectively) than in volunteers (181 ± 68 and 200 ± 75 s, respectively) (P < 0.01).
  
  
  CONCLUSIONS
  Our preliminary results indicate that diffusion-weighted MR imaging using a transient gustatory stimulation method is potentially useful for evaluating patients with xerostomia.
authors.affiliation: Department of Radiology, Gifu University School of Medicine, Gifu, Japan. hkato@gifu-u.ac.jp
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kato
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kanematsu
authors.forename: Makoto
authors.initials: M
authors.lastname: Toida
authors.forename: Tomoko
authors.initials: T
authors.lastname: Kawaguchi
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Shibata
authors.forename: Kimihiro
authors.initials: K
authors.lastname: Kajita
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Hoshi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D010812:Physical Stimulation / Q000379:methods; D011877:Radionuclide Imaging; D012016:Reference Values; D012463:Saliva / Q000378:metabolism*; D012469:Salivary Glands / Q000000981:diagnostic imaging* / Q000502:physiology*; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014987:Xerostomia / Q000175:diagnosis*