title: Diffusion Weighted Magnetic Resonance Imaging for the Characterization of Solitary Pulmonary Lesions.
abstract: BACKGROUND
  We evaluated the differential diagnosis of solitary pulmonary lesions on magnetic resonance imaging.
  
  
  OBJECTIVE
  To investigate the value of diffusion weighted imaging on the differential diagnosis of solitary pulmonary lesions.
  
  
  METHODS
  Randomized prospective study.
  
  
  METHODS
  This prospective study included 48 solitary pulmonary nodules and masses (18 benign, 30 malignant). Single shot echo planar spin echo diffusion weighted imaging (DWI) was performed with two b factors (0 and 1000 s/mm(2)). Apparent diffusion coefficients (ADCs) were calculated. On diffusion weighted (DW) trace images, the signal intensities (SI) of the lesions were visually compared to the SI of the thoracic spinal cord using a 5-point scale: 1: hypointense, 2: moderately hypointense, 3: isointense, 4: moderately hyperintense, 5: significantly hyperintense. For the quantitative evaluation, the lesion to thoracic spinal signal intensity ratios and the ADCs of the lesions were compared between groups.
  
  
  RESULTS
  On visual evaluation, taking the density of the spinal cord as a reference, most benign lesions were found to be hypointense, while most of the malignant lesions were evaluated as hyperintense on DWI with a b factor of 1000 s/mm(2). In contrast, on T2 weighted images, it was seen that the distinction of malignant lesions from benign lesions was not statistically significant. The ADCs of the malignant lesions were significantly lower than those of benign lesions (mean ADC was 2.02×10(-3) mm(2)/s for malignant lesions, and 1.195×10(-3)±0.3 mm(2)/s for benign lesions). Setting the cut-off value at 1.5×10(-3), ADC had a sensitivity of 86.7% and a specificity of 88.9% for the differentiation of benign lesions from malignant lesions.
  
  
  CONCLUSIONS
  DWI may aid in the differential diagnosis of solitary pulmonary lesions. (ClinicalTrials.gov Identifier: NCT02482181).
authors.affiliation: Department of Radiology, Kocaeli Derince Training and Research Hospital, Kocaeli, Turkey.
authors.forename: Çağlayan
authors.initials: Ç
authors.lastname: Çakır
authors.affiliation: Department of Radiology, Trakya University Hospital, Edirne, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Gençhellaç
authors.affiliation: Department of Radiology, Selçuk University Hospital, İzmir, Turkey.
authors.forename: Osman
authors.initials: O
authors.lastname: Temizöz
authors.affiliation: Department of Radiology, Edirne State Hospital, Edirne, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Polat
authors.affiliation: Department of Radiology, Trakya University Hospital, Edirne, Turkey.
authors.forename: Ersin
authors.initials: E
authors.lastname: Şengül
authors.affiliation: Department of Radiology, İzmir Katip Çelebi University Atatürk Training and Research Hospital, İzmir, Turkey.
authors.forename: Gökhan
authors.initials: G
authors.lastname: Duygulu
keywords: b factor; diffusion weighted magnetic resonance imaging; lung cancer; solitary pulmonary nodule