The aim of this study is to compare two different diagnostic methods (magnetic resonance imaging (MRI) and soluble forms of adhesion molecules: ICAM-1 and VCAM-1 measurement) in assessment of the activity of thyroid orbitopathy (TO) in patients with Graves' disease. 21 patients with infiltrative TO were treated with modified method by Bartalena et al. MRI scans and the measurement of soluble forms of ICAM-1 and VCAM-1 were performed before treatment, after methylprednisolone pulses along with radiotherapy of the retroorbital spaces and after the end of prednisone treatment. MRI scans did not reveal active stage of the disease in 4/21 patients with infiltrative TO, despite elevated levels of sICAM-1 and sVCAM-1. Patients both with active stage of the disease and with the results of MRJ scans revealing fibrotic changes in muscles responded well to therapy parallel with a significant decrease in levels of sICAM-1 and sVCAM-1. Levels of sVCAM-1 increased slightly under prednisone treatment despite improvement of clinical picture of TO, a significant decrease in sICAM-1 levels and in the number of muscles with active inflammatory process on MRI scans. In conclusion, serum levels of ICAM-1 seem to be more sensitive marker than MRI in assessment of the activity of TO. Concentrations of sVCAM-1 do not correspond with the clinical picture of the disease and the results of MRJ during treatment of TO.