title: Apparent diffusion coefficient values of mediastinal masses in children.
abstract: OBJECTIVE
  Compare apparent diffusion coefficient (ADC) values between benign and malignant mass lesions in a cohort of children referred for imaging of a mediastinal mass.
  
  
  METHODS
  Prospective study including 24 consecutive children (11 boys, 13 girls aged 5 months to 16 years). All underwent echo planar diffusion weighted MR imaging of the mediastinum with b-factors of 0 and 600 s/mm(2). Apparent diffusion coefficient (ADC) values were calculated and correlated with the surgical finding or biopsy.
  
  
  RESULTS
  The mean ADC value of malignant mediastinal tumors was 0.91 (S.D., 0.17) × 10(-3) mm(2)/s and of benign lesions 1.8 (S.D., 0.33) × 10(-3) mm(2)/s. There was significant different in the ADC value between malignant tumors and benign mediastinal tumors (P<0.001). Selection of 1.2 × 10(-3) mm(2)/s as a threshold value for differentiating malignant from benign mediastinal masses has an accuracy of 93%, sensitivity of 92%, specificity of 94%, positive predictive value of 94%, negative predictive value of 92% and area under the curve of 0.962.
  
  
  CONCLUSIONS
  Apparent diffusion coefficient value is a promising non-invasive parameter for assessment of mediastinal mass in children.
authors: Diagnostic Radiology Department, Mansoura Faculty of Medicine, Mansoura, Egypt. arazek@mans.edu.eg
authors: Ahmed Abdel Khalek
authors: AA
authors: Abdel Razek
authors: Nermin
authors: N
authors: Soliman
authors: Rasha
authors: R
authors: Elashery
mesh_terms: D000293:Adolescent; D019540:Area Under Curve; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008479:Mediastinal Neoplasms / Q000473:pathology*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric