Quantitative digital subtraction angiography to localize intercostal arteries during thoracic endovascular aortic repair

The accurate identification and preservation of critical intercostal arteries are important technical issues during thoracic endovascular aortic repair (TEVAR) to reduce the risk of postoperative paraparesis. The localization of intercostal arteries by digital subtraction angiography (DSA) before deployment of a stent graft is often difficult because of their small caliber and posterior orientation. Parametric color coding is an imaging software that measures flow dynamics in a DSA series and provides quantitative information without the additional cost of an X ray dose and contrast medium. In a single image, quantitative DSA (Q-DSA; syngo iFlow software; Siemens, Forchheim, Germany) provides information on the transit of contrast medium through vessels We describe the use of Q-DSA to localize and preserve the intercostal arteries in the distal descending aorta during TEVAR.