The study of whole body diffusion weighted imaging application in bone metastasis

Objective: To evaluate the value of whole-body DWI (WB-DWI) in bone metastasis. Methods: WB-DWI was performed on 10 healthy volunteers and 35 patients with bone metastasis. WB-DWI and ECT was performed in all 35 patients to detect bone metastasis and compared the result between two methods with a chi-square test, P<0.05. Results: (1) Background tissue was suppressed in WB-DWI, fat, muscle, vessels and liver appeared the same as background. Skeleton showed medium or slightly lower signal. Lymph nodes, some glandular organs, kidneys were showed medium signal. Spleen, testicle, brain tissue were low signal, bladder, gallbladder were depicted as low signal because of 'T2 through' effect. Bone metastasis were multitude and inequality of size, punctiform, nodosity, or column low intensity. (2) Concordance between WB-DWI and ECT was seen only in 4 case, while in total WB-DWI displayed 1 bone metastasis on skull, 46 on rib and sternum, 3 on scapula, 4 on extremities, 83 on vertebral, 36 on pelvic bone. ECT showed 2 bone metastasis on skull, 62 on rib and sternum, 7 on scapula, 9 on extremities, 64 on vertebral, 19 on pelvic bone. WB-DWI was recognizable for 74% bone metastasis on rib and sternum, ECT was 77%, 53% for vertebral and pelvic bone (P<0.05). Total distribution probability varied for metastasis of different location. Conclusion: WB-DWI was a sensitive method for' screening bone metastasis. (authors)