fig1

Figure 1. Classification of thoracoabdominal aortic aneurysm (TAAA) extent based on Crawford. In Extent I the repair comprises most of the descending thoracic and upper abdominal aorta; Extent II involves most of the descending thoracic aorta and most or all of the abdominal aorta; Extent III involves the distal descending thoracic aorta and varying segments of abdominal aorta; and Extent IV involves most or all of the abdominal aorta including the segment from which the visceral vessels arise. (Reproduced by permission of Mayo Foundation for Medical Education and Research. All rights reserved).