Clinical importance and configuration of collateral vessel systems in patients with Takayasu arteritis or with thymoma visualized by three-dimensional volume rendering computed tomographic angiography

Background Collateral vessels form after gradual blood vessel occlusion. We speculate that in Takayasu arteritis (TA) and thymoma patients, before planning surgical procedures, a complex artery/venous system should be examined using three dimensional (3D) volume rendering computed tomographic (CT) angiography. Purpose To seek the clinical importance and actual complex configuration of collateral vessel systems in patients with TA or with thymoma using 3D volume rendering CT angiography with special acquisition method. Methods We performed 3D CT angiography in patients with Takayasu arteritis (TA) with occluded arteries (N=6) or thymoma (N=2) with occluded superior-vena-cava (SVC), respectively. For CT angiography in thymoma patients, diluted (1/4) iodinated-contrast was injected in right and left medial cubital-veins simultaneously, and images acquired 10 seconds after contrast-injection. Results Occluded and collateral-arteries (TA group) and occluded SVC and collateral-veins (thymoma group) were successfully visualized (Figures a-h). Collateral-arteries form from the inferior mesenteric artery (Figure a) or de novo arteries from the abdominal aorta (Figure b) after superior mesenteric artery occlusion (Figure c, d). In patients with thymoma, an SVC thymoma disrupts venous return in the neck and upper extremities; a complex venous system forms on the abdominal surface (Figure e-h). Conclusion In TA and thymoma patients, before planning surgical procedures, a complex artery/venous system should be examined using 3D volume rendering CT angiography. For CT in thymoma, diluted (1/4) iodinated contrast should be injected in both medial cubital veins, and images should be acquired 10 seconds after contrast-injection. 3D volume rendering CT angiography Funding Acknowledgement Type of funding source: None