title: Diffusion-weighted imaging in the head and neck region: usefulness of apparent diffusion coefficient values for characterization of lesions.
abstract: OBJECTIVE
  We aimed to evaluate the role of apparent diffusion coefficient (ADC) values calculated from diffusion-weighted imaging for head and neck lesion characterization in daily routine, in comparison with histopathological results.
  
  
  METHODS
  Ninety consecutive patients who underwent magnetic resonance imaging (MRI) at a university hospital for diagnosis of neck lesions were included in this prospective study. Diffusion-weighted echo-planar MRI was performed on a 1.5 T unit with b factor of 0 and 1000 s/mm2 and ADC maps were generated. ADC values were measured for benign and malignant whole lesions seen in daily practice.
  
  
  RESULTS
  The median ADC value of the malignant tumors and benign lesions were 0.72×10-3 mm2/s, (range, 0.39-1.51×10-3 mm2/s) and 1.17×10-3 mm2/s, (range, 0.52-2.38×10-3 mm2/s), respectively, with a significant difference between them (P < 0.001). A cutoff ADC value of 0.98×10-3 mm2/s was used to distinguish between benign and malignant lesions, yielding 85.3% sensitivity and 78.6% specificity. The median ADC value of lymphomas (0.44×10-3 mm2/s; range, 0.39-0.58×10-3 mm2/s) was significantly smaller (P < 0.001) than that of squamous cell carcinomas (median ADC value 0.72×10-3 mm2/s; range, 0.65-1.06×10-3 mm2/s). There was no significant difference between median ADC values of inflammatory (1.13×10-3 mm2/s; range, 0.85-2.38×10-3 mm2/s) and noninflammatory benign lesions (1.26×10-3 mm2/s; range, 0.52-2.33×10-3 mm2/s).
  
  
  CONCLUSIONS
  Diffusion-weighted imaging and the ADC values can be used to differentiate and characterize benign and malignant head and neck lesions.
authors.affiliation: Department of Radiology, Bulent Ecevit University School of Medicine, Zonguldak, Turkey. driserif@yahoo.com.
authors.forename: İsmail
authors.initials: İ
authors.lastname: Şerifoğlu
authors.forename: İbrahim İlker
authors.initials: İİ
authors.lastname: Oz
authors.forename: Murat
authors.initials: M
authors.lastname: Damar
authors.forename: Özlem
authors.initials: Ö
authors.lastname: Tokgöz
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Yazgan
authors.forename: Zuhal
authors.initials: Z
authors.lastname: Erdem
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging; D005260:Female; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008223:Lymphoma / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D000077195:Squamous Cell Carcinoma of Head and Neck; D055815:Young Adult