Takayasu's arteritis: Assessment of disease activity with contrast-enhanced MR imaging

OBJECTIVE. The purpose of this study was to evaluate the role of contrast-e nhanced MR imaging in the determination of disease activity in patients wit h Takayasu's arteritis. SUBJECTS AND METHODS. High-resolution contrast-enhanced T1-weighted spin-ec ho MR imaging using small fields pf view (14-20 cm) and thin slices (4-5 mm ) was per formed in 26 patients with Takayasu's arteritis and 16 healthy su bjects. The degree of aortic mural enhancement was assessed by measuring si gnal intensity and by visually estimating it in comparison with that of the myocardium. RESULTS. Contrast-enhanced MR imaging showed more enhancement of thickened aortic wall compared with myocardium, thus suggesting active Takayasu's art eritis on MR imaging in 16 patients. Determination of disease activity usin g contrast-enhanced MR imaging was concordant with clinical findings in 23 patients (88.5%). Contrast-enhanced MR findings were concordant with labora tory findings in most patients (erythrocyte sedimentation rate in 92.3% [24 /26] and C-reactive protein in 84.6% [22/26]), The measured signal intensit y of the aortic wall relative to that of myocardium during the early phase of contrast-enhanced MR imaging correlated well with the erythrocyte sedime ntation rate (r = 0.78, p < 0.005) and with the C-reactive protein level (r = 0.63, p < 0.005). CONCLUSION. Contrast-enhanced MR imaging provides information about disease activity of Takayasu's arteritis, which may be useful in the diagnosis and treatment of Takayasu's arteritis.