Assessment of Disease Activity in Takayasu Arteritis: Potential Role of Contrast-Enhanced Ultrasound.

Purpose:  To assess the diagnostic value of intima media thickness measurements and contrast-enhanced ultrasound (CEUS) of the supraaortic arteries in the assessment of disease activity in Takayasu arteritis (TA).

Materials And Methods:  Patients with TA and involvement of the carotid and/or subclavian/axillary arteries underwent CEUS imaging in addition to B-mode and color duplex ultrasound. The maximum IMT (mIMT) was measured and high-resolution CEUS of the most prominently thickened vessel segment was performed. Two blinded readers reviewed the CEUS movies, with semiquantitative assessment of microbubble enhancement of the arterial wall (grade 0: no or minimal; grade 1: moderate; grade 2: pronounced). Clinical symptoms, acute phase reactants, and established indices of clinical disease activity (NIH criteria, ITAS score) were recorded.

Results:  40 examinations in 17 patients were analyzed. According to clinical judgement, 27 and 13 cases were classified as clinically inactive and active, respectively. An mIMT-cutoff of > 2.7 mm identified active disease with a sensitivity and specificity of 69.2 % and 88.9 %, respectively (area under the curve 0.83). The interobserver agreement of CEUS analysis was substantial (Cohen's kappa 0.76). By consensus reading, 17, 15, and 8 cases were classified as uptake grade 0, grade 1 and grade 2, respectively. Grade 0 uptake was exclusively present in 17 clinically inactive patients. Grade 1 uptake was seen in 10 patients with clinically inactive disease and 5 patients with clinically active disease. Grade 2 uptake was exclusively present in 8 patients with active disease.

Conclusion:  Both sonographic IMT measurements and high-resolution CEUS are promising in the ad-hoc assessment of disease activity in patients with TA.