The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document. Reprint requests to: publications@acr.org Regardless of the pathology at play, the TEVAR procedure is similar. Access in TEVAR procedures is increasingly obtained percutaneously via the common femoral artery, although femoral artery cutdowns are still performed in up to 20% of cases. Although obesity was once considered a relative contraindication to percutaneous access, recent literature has demonstrated that it does not affect procedural success rates in the hands of an experienced surgeon or interventionalist [24]. The most important factor in percutaneous vessel selection appears to be vessel diameter, with common femoral artery diameters >8 to 9 mm exhibiting lower rates of complication [25,26]. Careful attention to preoperative imaging is then paid to the involved landing zones of the thoracic aorta. Proximal and distal landing zones should ideally be 2 to 3 cm in length to ensure an adequate seal and decreased rates of endoleaks, aneurysmal degeneration, and device migration [27]. When the proximal landing zone approaches the aortic arch vessels, the possibility of the stent graft occluding a vessel ostium arises. In such cases, vascular bypass or a staged or hybrid approach may be necessary to ensure patency. If aortic pathology extends into the abdominal aorta, care must be taken to assess for possible stent coverage of major branch vessels; when this situation arises, more involved repairs are necessary.
Thoracic Aortic Aneurysm or Dissection Treatment Planning and Follow Up. The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply individual or society endorsement of the final document. Reprint requests to: publications@acr.org Regardless of the pathology at play, the TEVAR procedure is similar. Access in TEVAR procedures is increasingly obtained percutaneously via the common femoral artery, although femoral artery cutdowns are still performed in up to 20% of cases. Although obesity was once considered a relative contraindication to percutaneous access, recent literature has demonstrated that it does not affect procedural success rates in the hands of an experienced surgeon or interventionalist [24]. The most important factor in percutaneous vessel selection appears to be vessel diameter, with common femoral artery diameters >8 to 9 mm exhibiting lower rates of complication [25,26]. Careful attention to preoperative imaging is then paid to the involved landing zones of the thoracic aorta. Proximal and distal landing zones should ideally be 2 to 3 cm in length to ensure an adequate seal and decreased rates of endoleaks, aneurysmal degeneration, and device migration [27]. When the proximal landing zone approaches the aortic arch vessels, the possibility of the stent graft occluding a vessel ostium arises. In such cases, vascular bypass or a staged or hybrid approach may be necessary to ensure patency. If aortic pathology extends into the abdominal aorta, care must be taken to assess for possible stent coverage of major branch vessels; when this situation arises, more involved repairs are necessary.