Takayasu arteritis: evaluation of the thoracic aorta with CT angiography.

Abstract

To determine the diagnostic accuracy of computed tomographic (CT) angiography in the evaluation of Takayasu arteritis. Twenty-five patients with clinical symptoms suggestive of Takayasu arteritis underwent CT angiography and conventional angiography. Takayasu arteritis was diagnosed in 20 patients on the basis of conventional angiography. CT angiography was performed with a helical CT scanner after injection of a bolus of contrast material, and images were generated for three-dimensional display, multiplanar reformation, and maximum intensity projection. For vascular assessment, all images from CT angiography were used, and the results were compared with those from conventional angiography. CT angiography clearly depicted various luminal changes, including stenosis, occlusion, dilatation, and aneurysm, in the thoracic aorta and its major branches. CT angiography accurately depicted 190 (95%) of 200 arteries, although the extent of the steno-occlusive lesions was overestimated in five (2%) and underestimated in five (2%). Furthermore, CT angiography depicted mural changes, including wall thickening, calcification, and mural thrombi, not seen with conventional angiography. The sensitivity and specificity of CT angiography in the diagnosis of Takayasu arteritis were 95% and 100%, respectively. CT angiography clearly depicts both luminal and mural changes in the thoracic aorta and its major branches and has a high accuracy in the diagnosis of Takayasu arteritis.