title: Differentiation of benign and malignant skeletal lesions with quantitative diffusion weighted MRI at 3T.
abstract: OBJECTIVE
  To investigate the accuracy of quantitative diffusion-weighted imaging with apparent diffusion coefficient (ADC) mapping for characterizing bone lesions as benign or malignant.
  
  
  METHODS
  At 3T, 31 subjects with intramedullary lesions imaged by DWI (b-values 50, 400, 800s/mm(2)) were included. ADC values (minimum, mean, maximum) were recorded by three observers independently. Interobserver variability and differences between ADC values in benign and malignant lesions were assessed (unpaired t-test, receiver operating characteristic (ROC) analysis).
  
  
  RESULTS
  Of 31 lesions, 18 were benign (osteoblastic (n=1), chondroid (n=6), cysts (n=4), hemangiomatosis (n=1), fibrous (n=3), eosinophilic granuloma (n=1), giant cell tumor (n=1), osteomyelitis (n=1)) and 13 were malignant (primary (n=5), metastases (n=8)). Overall, there were higher minimum (1.27 × 10(-3)mm(2)/s vs 0.68 × 10(-3)mm(2)/s, p<0.001), mean (1.68 × 10(-3)mm(2)/s vs 1.13 × 10(-3)mm(2)/s, p<0.001), and maximum (2.09 × 10(-3)mm(2)/s vs 1. 7 × 10(-3)mm(2)/s, p=0.03). ADC values in benign lesions compared with those in malignancies. ROC analysis revealed areas under the curve for minimum, mean, and maximum ADC values of 0.91, 0.85, and 0.71, respectively. ADC measurements were made with high inter-observer concordance (ρ=0.83-0.96).
  
  
  CONCLUSIONS
  Quantitative ADC maps may have predictive value for the characterization of bone lesions. Benign lesions generally have higher minimum, mean, and maximum ADC values than malignancies, with the minimum value offering the highest accuracy for characterization.
authors: The Russell H. Morgan Department of Radiology & Radiological Science, The Johns Hopkins University School of Medicine, 601 North Wolfe Street, Baltimore MD 21287, United States. Electronic address: sahlawa1@jhmi.edu.
authors: Shivani
authors: S
authors: Ahlawat
authors: The Russell H. Morgan Department of Radiology & Radiological Science, The Johns Hopkins University School of Medicine, 601 North Wolfe Street, Baltimore MD 21287, United States. Electronic address: pkhandh1@jhmi.edu.
authors: Paras
authors: P
authors: Khandheria
authors: Department of Radiology (R-109), University of Miami Leonard M. Miller Miami, FL 33101, United States. Electronic address: TSubhawong@med.miami.edu.
authors: Ty K
authors: TK
authors: Subhawong
authors: The Russell H. Morgan Department of Radiology & Radiological Science, The Johns Hopkins University School of Medicine, 601 North Wolfe Street, Baltimore MD 21287, United States. Electronic address: lfayad1@jhmi.edu.
authors: Laura M
authors: LM
authors: Fayad
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001847:Bone Diseases / Q000175:diagnosis*; D001859:Bone Neoplasms / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012372:ROC Curve; D015203:Reproducibility of Results; D055815:Young Adult
keywords: ADC map; Bone tumors; Diffusion-weighted imaging; Musculoskeletal