MR imaging with static and dynamic Gd-DTPA studies in neoplasms of the musculoskeletal system

In 95 patients with bone and soft-tissue tumors, T1- and T2-weighted spin-echo (SE) sequences without contrast enhancement and Gd-DTPA-enhanced T1-weighted SE sequences were acquired. Although gadolinium-enhanced T1-weighted images exhibited characteristics similar to those of T2-weighted images, the contrast of tumor to muscle was about 50% lower. Viable tumor tissue could be reliably differentiated from necrosis only after Gd-DTPA administration. Dynamic changes in signal intensity were assessed by means of a 12 times fast low-angle shot (FLASH) 900 sequence repeated 12 times. In bone marrow, fat, muscle, and necrotic tumor tissue, no or only moderate signal increase was observed. In malignant tumors, the signal increase was significantly more pronounced and rapid than in benign tumors and more rapdi than inperitumorous edema