MR imaging of experimental and clinical thrombi at 1.5 T

We have previously reported the T₁ and T₂ of experimental clots at 0.47 T varies considerably depending upon the method used in their preparation. However, these studies, while relevant to midfield imaging, may not reflect accurately the behavior of such thrombi at higher field strengths. Accordingly, we studied the T₁ and T₂ at 1.5 T of experimental thrombi prepared by several methods and compared these results with the relaxation times of clinical deep venous thrombi measured in situ in patients. The relationship between the T₂ values for the different clot preparation methods was different at 1.5 T than at 0.47 T. The combined use of thrombin and epsilon-amino caproic acid produced thrombi with T₁ and T₂ indistinguishable from clinical deep venous thrombi.