title: Diffusion-weighted MRI for differentiation between sialadenitis and pleomorphic adenoma.
abstract: OBJECTIVE
  The aim of this study was to compare apparent diffusion coefficient (ADC) values from diffusion-weighted MRI (DWI) among normal salivary glands, cases with sialadenitis and cases with pleomorphic adenoma of major salivary glands.
  
  
  METHODS
  22 patients (totalling 44 major salivary glands) diagnosed with either unilateral sialadenitis (on either parotid or submandibular gland) or parotid gland pleomorphic adenoma were selected. Contralateral non-affected glands (normal) were also analyzed. DW images were achieved using a spin-echo pulse sequence with a 1.5-T MRI device. Mean ADC values were compared among the three groups analyzed (contralateral normal glands, sialadenitis and pleomorphic adenoma).
  
  
  RESULTS
  The mean ADC values were significantly higher in cases of parotid sialadenitis (p = 0.001), but not in cases of submandibular sialadenitis (p = 0.466), as compared with the contralateral non-affected glands. Cases of pleomorphic adenoma presented the highest ADC values of the study. In addition, one-way ANOVA test revealed a significant difference among the three groups of parotid glands analyzed.
  
  
  CONCLUSIONS
  Within the limitations of this study, the present results suggest that DWI allows for differentiation between parotid sialadenitis and pleomorphic adenoma.
authors.affiliation: 1 Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Guilherme T C
authors.initials: GT
authors.lastname: Terra
authors.affiliation: 1 Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Jefferson X D
authors.initials: JX
authors.lastname: Oliveira
authors.affiliation: 2 Department of Oral Radiology, Clinica Felix Boada, Caracas, Venezuela.
authors.forename: Adalsa
authors.initials: A
authors.lastname: Hernandez
authors.affiliation: 1 Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Silvia V
authors.initials: SV
authors.lastname: Lourenço
authors.affiliation: 1 Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Emiko S
authors.initials: ES
authors.lastname: Arita
authors.affiliation: 1 Department of Stomatology, School of Dentistry, University of São Paulo, São Paulo, Brazil.
authors.forename: Arthur R G
authors.initials: AR
authors.lastname: Cortes
mesh_terms: D008949:Adenoma, Pleomorphic / Q000000981:diagnostic imaging* / Q000473:pathology; D000328:Adult; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D012468:Salivary Gland Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D012793:Sialadenitis / Q000000981:diagnostic imaging* / Q000473:pathology
keywords: MRI; diffusion-weighted imaging; pleomorphic adenoma; salivary glands