title: Diffusion-weighted echoplanar MR imaging of the salivary glands.
abstract: OBJECTIVE
  We determined the apparent diffusion coefficients of normal and dysfunctional salivary glands.
  
  
  METHODS
  A diffusion-weighted single-shot spin-echo type of echoplanar MR imaging was performed on the parotid or submandibular glands, or both, in 36 healthy subjects, 20 patients with Sjögren's syndrome, and six patients with sialoadenitis. The apparent diffusion coefficient of the salivary gland was calculated using two b factors (b = 500 and 1,000 sec/mm(2)).
  
  
  RESULTS
  The apparent diffusion coefficient was lower in the parotid glands (0.28 x 10(-3) mm(2)/sec) than that of the submandibular glands (0.37 x 10(-3) mm(2)/sec). The apparent diffusion coefficient was increased in sialoadenitis, whereas it decreased with abscess formation. The apparent diffusion coefficients of the parotid glands in patients with Sjögren's syndrome correlated with the salivary flow rates but not with the sialographic gradings of the glands. We also found a correlation of the decreases in apparent diffusion coefficients with the severity of gland damage as assessed on T1-weighted MR images.
  
  
  CONCLUSIONS
  Diffusion-weighted echoplanar MR imaging may reveal diseased states of the salivary glands.
authors.affiliation: Department of Radiology and Cancer Biology, Nagasaki University School of Dentistry, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan.
authors.forename: Misa
authors.initials: M
authors.lastname: Sumi
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Takagi
authors.forename: Masataka
authors.initials: M
authors.lastname: Uetani
authors.forename: Minoru
authors.initials: M
authors.lastname: Morikawa
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Hayashi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kabasawa
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Aikawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology*; D012463:Saliva / Q000378:metabolism; D012793:Sialadenitis / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology; D012859:Sjogren's Syndrome / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology; D013363:Submandibular Gland / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology*