Aim of the study: The aim of the study was the evaluation of the diffusion coefficient (ADC) of vertebral metastasis and regular vertebral bodies with diffusion weighted MRI (DWI). DWI evaluates the tissue-specific molecular diffusion of protons. In tissues with high cell densities (neoplasm) a decreased ADC can be expected due to restricted diffusion according to an exaggerated amount of intra- and intercellular membranes (i.e. diffusion barriers).
Methods: In 5 breast cancer patients the ADC of both known vertebral metastases and of adjacent regular vertebral bodies were measured with DWI (1.0 T; Phased-Array-Body-Coil; b: 880 and 440 s/mm2).
Results: The ADC of regular vertebral bodies (1.3 +/- 0.23 x 10(-3) s/mm2) was significantly (p < or = 0.0002) higher than in vertebral metastases (0.39 +/- 0.11 x 10(-3) s/mm2).
Conclusions: These data demonstrate that the ADC can be reliably measured in vertebral bodies. The quantitative evaluation of the ADC in vertebral bodies seems to be an objective and comparable parameter for differentiating malign from benign vertebral tissue.