The Application of Whole Body Diffusion Weighted Imaging with Background Body Signal Suppression in the Diagnosis of Thoracic Tumorous Lesions

Objective:To evaluate the role of DWIBS in the diagnosis of thoracic tumorous lesions.Materials and Methods:102 cases (patients suspected chest tumors clinically in Beijing Coal General Hospital from 01, 2009 to 12, 2010, total 158 lesions) were involved in this study, including 33 lung cancer, 18 pulmonary benign tumorous lesions, 24 malignant lymphoma, 24 mediastinal and subaxillary lymph node metastasis, 22 breast cancer, 17 breast benign lesions and 20 focal normal breast tissues.All 158 lesions were performed DWIBS (STIR) examination and 33 of them also received DWIBS (SPIR) examination and another 4 cases received thoracic-abdomen-pelvis DWIBS (STIR) scan, then their ADC value were measured and compared.The lesions were displayed by background suppression rebuilding with 3D MIP (3 dimensional maximum intensity projection) and technique with reverse black and white.The ADC values of all lesions were measured.Results: (1) The effect of background suppression of STIR-EPI was better than SE-EPI (SPIR) and could get PET-like images with 3D MIP rebuilding and reverse black and white technique to observe the lesion more clearly. (2) The mean ADC value of thoracic metastatic lymph nodes was 1.37±0.41 mm²/s×10^-3 and 0.91±0.12 mm²/s×10^-3in thoracic lymphoma.There was significant difference between them (P<0.05);The mean ADC value of lung cancer was 1.61±0.18 mm²/×10^-3 and 2.06±0.21 mm²/×10^-3 in pulmonary benign lesions, and it was significantly ower than that of benign lesions. (3) The ADC value of different types of malignant different between the two types of lesions;The mean ADC value of breast cancer, breast benign lesion and normal breast tissue was 1.01±0.13 mm²/×10^-3, 1.81±0.18 mm²/×10^-3 and 1.91±0.26 mm²/×10^-3 respectively, and there was significant difference between either two groups. (3) The ADC values of different types of malignant tumors were significantly different. (4) Among the 4 cases with thoracic-abdomen and pelvis DWIBS examination, 3 cases were with distal metastasis.Conclusions: (1) DWIBS was a safe and effective imaging examination. (2) It benefited to identify the property of the thoracic tumorous lesion that was benign or malignant, the ADC value of malignant lesions was lower than that of benign lesions. (3)The ADC value of different types of malignant tumors was significantly different. (4) DWIBS can be used in tumor screening and the therapeutic evaluation due to its large range scan.