Diagnostic Value of CT Virtual Intravascular Endoscopy in Aortic Stent-Grafting

Abstract

VIE was not found to play a role in most preoperative situations compared to axial CT images. However, VIE provided additional postgrafting information on the 3D relationship of the suprarenal stent struts to the aortic branch ostia (in particular the renal and superior mesenteric arteries). VIE findings might aid clinicians in accurately assessing the effect of suprarenal stent-grafting on the renal arteries.

Multislice CT angiography in post-aortic stent grafting: optimization of scanning protocols for virtual intravascular endoscopy

“…Operation with 16-and 64-slice CT and gantry rotation time of 0.5 or 0.33 s reduce scanning time and result in acquisition of isotropic volume data. CT VIE is currently being assessed as an additional 3D image method to conventional imaging techniques for postoperative follow-up of aortic stent grafts [8,10]. No clear consensus exists, however, on issues regarding MSCT VIE acquisition parameters.…”

“…MSCT volume data were converted from original DICOM (Digital Imaging and Communication in Medicine) images with a commercially available software Analyze V 7.0 (Analyze V, AnalyzeDirect, Inc., Lexana, KS, USA). Detailed generation of VIE images of the aortic ostium and suprarenal stent wires has been discussed elsewhere [8,9]. Similar to our previous studies, we used a CT thresholding technique to produce endoscopic views of the aortic ostium and stent wires with minimal artifacts.…”

“…For generation of VIE images of stent wires, the lower threshold was selected to remove all of the soft tissue while keeping the high density stent wires. An appropriate threshold allows visualization of stent wires clearly without breaking or discontinuous appearance being observed [8].…”

“…The role of CTA has been greatly enhanced by the introduction of multislice CT (MSCT) due to its fast scanning, high spatial and temporal resolution and acquisition of nearly isotropic volume data [7]. CTA-generated virtual intravascular endoscopy (VIE) is a rapidly evolving technology that permits interactive 3D visualizations not only for aortic branches but also for intraluminal stents [8][9][10]. VIE has been reported to provide additional information when compared to conventional 2D and 3D visualizations in earlier studies [8,9], and it was considered to be a valuable visualization tool that assists vascular surgeons to accurately evaluate the treatment outcomes of endovascular repair.…”

“…CTA-generated virtual intravascular endoscopy (VIE) is a rapidly evolving technology that permits interactive 3D visualizations not only for aortic branches but also for intraluminal stents [8][9][10]. VIE has been reported to provide additional information when compared to conventional 2D and 3D visualizations in earlier studies [8,9], and it was considered to be a valuable visualization tool that assists vascular surgeons to accurately evaluate the treatment outcomes of endovascular repair. Specifically, VIE was found to play a role in the following two aspects: providing unique information about the configuration and number of suprarenal stent wires crossing the renal artery ostia, and assessing the morphological change of the renal artery ostia following suprarenal stent graft placement [11,12].…”