OBJECTIVETo evaluate the feasibility and clinical value of whole body diffusion weighted magnetic resonance imaging (WB-DWI) in detection of bone metastases.

METHODSTotally 38 patients with malignant tumors and suspected bone metastases were enrolled. All patients underwent WB-DWI and bone scintigraphy within 2 weeks. The skeletal system was divided into 13 regions: skull, sternum, clavicle, cervical spine, thoracic spine, lumbar spine, sacrum, ribs, pelvic bone, scapula, humerus, femur, and tibia/fibula. Bone metastases were assessed for both modalities in a separate consensus reading and apparent diffusion coefficient (ADC) values were calculated.

RESULTSWB-DWI identified 214 pathological lesions in 20 patients, while bone scintigraphy demonstrated 197 lesions in 20 patients. Concordance between WB-DWI and bone scintigraphy occurred in 34 of 38 patients. There was no statistical difference between these two modalities (P = 0.488). Compared with bone scintigraphy, the regions missed by WB-DWI were mainly located in skull, thoracic spine, humerus, and tibia/fibula. WB-DWI was more sensitive in the detection of metastases to the cervical spine, lumbar spine, sacrum, pelvis, ribs and femur. No statistical significance was found among the ADC values of bone metastases in different skeletal areas, and the mean ADC value was (0.75 +/- 0.10) x 10(-3) mm2/s. Furthermore, WB-DWI revealed more metastases to the lymph lodes and extraskeletal organs. Conclusion WB-DWI has high accordance with skeletal scintigraphy in detecting bone metastases, and the two modalities are complementary to each other.