1. An evaluation of centerline of flow measurement techniques to assess migration after thoracic endovascular aneurysm repair 
Sean O’Neill, MD, Roy K. Greenberg, MD, Timothy Resch, MD, Shona Bathurst, Donna Fleming, RN, Vikram Kashyap, MD, Sean P. Lyden, MD, Daniel Clair, MD 
Journal of Vascular Surgery 
Volume 43, Issue 6, Pages (June 2006)
DOI: /j.jvs
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

2. Fig 1
A three-dimensional reconstruction of the thoracic aorta with a stent graft is depicted in the setting of a bovine arch after intentional occlusion of the left subclavian artery. The white lines demonstrate a mock set of axial images. Nearly half of the covered aorta is oriented parallel (red arrow) to the axial images. This renders the assessment of axial images to determine the stability, or lack thereof, of the proximal fixation system inaccurate.
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

3. Fig 2
A two-dimensional stretched view of the thoracic aorta based on images recreated perpendicular to the calculated centerline of flow is depicted (A). Cross-sectional images perpendicular to the centerline of flow at various locations are demonstrated (B-G). The distance between the left common carotid artery (LCCA; B) and the celiac artery (CA; C) provide data regarding the thoracic aortic length. They also represent the native landmarks used to calculate the distance from the respective fixation system. The initial appearances of the proximal and distal fixation systems are depicted in images D and G, whereas the circumferential stent images are depicted in images E and F.
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

4. Fig 3
The visual identification of calcification patterns (circled) allows for the determination of device movement in relation to markers that are in the immediate proximity of the fixation systems. In this image, the centerline of flow data calculated a distal migration of the proximal fixation stent of 14 mm. However, it is clear that the aorta between the LCCA and the proximal stent has lengthened, and the device has remained stable in relation to the island of calcium immediately proximal to the device.
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

5. Fig 4
Initial postprocedure imaging of an endovascular second-stage elephant trunk procedure demonstrates a tortuous elephant trunk without evidence of complications. Three years after the completed repair, marked morphologic changes to the diameter and length of the surgically placed polyester graft are noted, yet the position of the endovascular graft within the elephant is unchanged. The centerline of flow analysis yielded a migration distance approaching 70 mm, yet the position of the stent graft within the elephant trunk graft (ETG) is unchanged. Reprinted with permission from Lippincott, Williams & Wilkins ©2005. (Circulation 2005;112: )
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

6. Fig 5
Summary of patients who were screened and analyzed for this study.
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

7. Fig 6
Distal migration of the proximal stent graft was demonstrated in a patient 3 years after a Zenith TX2 device was placed. Initially, coverage of the left subclavian artery was accomplished (blue line); however, slight dilation of the proximal neck was noted coincident with device migration. The device now resides 18 mm distal to the initial position. It is interesting to note that the image resolution has allowed interrogation of the aortic wall, in which the migration path of device migration is readily apparent (groove by the red arrow). Furthermore, no fractures of the barbs protruding through the wall were noted (the yellow arrow denotes the barb). Similarly, no damage to the wall was detected despite the caudal track of the hooks.
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions

8. Fig 7
Stent graft reconstruction of a noncontrast CT scan by using a 70 Kernal (high-resolution edge-detection) is shown here. Two surgical clips have been placed at the terminal end of the elephant trunk graft (red arrow), as well as a pacing wire, which was sutured to the outside of the graft (white arrow). These landmarks, coupled with the observed diameter of the stent-graft expansion within the elephant trunk graft in contrast to complete stent expansion in the aneurysm, allow for accurate assessment of the endovascular device. In this example, approximately one and a half stents remain fixed within the fabric of the elephant trunk (ET) on the postoperative imaging study and 1 year later, despite any morphologic changes that may have occurred to the more proximal elephant trunk graft.
Journal of Vascular Surgery  , DOI: ( /j.jvs )
Copyright © 2006 The Society for Vascular Surgery Terms and Conditions