Use of Synchrotron Radiation to Accurately Assess Cross-Sectional Area Reduction of the Aortic Branch Ostia Caused by Suprarenal Stent Wires

Abstract

CTA has inferior spatial resolution that hinders accurate assessment of CSA reduction. This experiment demonstrated the superiority of synchrotron radiation over CTA for more accurate assessment of aortic stent wires and CSA reduction of the aortic branch ostia.

Synchrotron radiation computed tomography versus conventional computed tomography for assessment of four types of stent grafts used for endovascular treatment of thoracic and abdominal aortic aneurysms

“…due to inferior spatial resolution, with overestimation of wire diameters to more than 2-fold than the actual sizes. This is confirmed in this study and previous reports with measured wire diameters ranging from 0.7 to 2.44 mm, while the actual stent wire sizes were measured between 0.32 and 0.48 mm (25,26). Therefore, routine CT imaging is a useful technique for follow-up of position of stent grafts in relation to the aortic branches, and patency of stented vessels, but not for accurate assessment of wire diameters with regard to the hemodynamic effects on renal arteries or cross-sectional area reduction due to presence of stent wires across the renal artery ostium.…”

“…Synchrotron radiation CT imaging was conducted at the Australian Synchrotron in Melbourne using the Imaging and Medical Beamline (IMBL). Details of experimental setup and imaging characteristics of IMBL have been described in our previous studies (25,26). The synchrotron radiation CT images were acquired with a pixel size of 41.6 μm and beam energies ranging from 60 to 90 keV with 10 keV increment at each scan.…”

“…The purpose of selecting different beam energies was to determine the effect of energies on the visualization of stent wires and identify optimal energy range for synchrotron radiation CT imaging of aortic stent grafts. The rationale of choosing 60 keV as the minimal beam energy and 90 keV as the maximum was based on our previous study findings, beam energy lower than 60 keV resulting in suboptimal visualization of stent wires, while beam energy higher than 90 keV leading to disruption of wire structures (25,26). To ensure that the model did not move during synchrotron radiation CT imaging, the model was immobilized by foam boards fixed to the centre of IMBL scan table as shown in Figure 4.…”

“…The limitation of inferior spatial resolution of current CT systems can be overcome by synchrotron radiation CT due to its advantage of superior spatial resolution, which is more than ten times higher than the most recent CT scanners (23,24). Our recent studies have shown the accuracy of synchrotron radiation CT for accurate assessment of stent wires and cross-sectional area reduction caused by aortic stent grafts (25,26). However, the study was limited to only imaging one particular type of stent graft.…”

Insights into 3D printing in medical applications

“…Coronary CT angiography has low to moderate diagnostic accuracy in determining coronary stenosis caused by heavily calcified plaques due to beam hardening and blooming artifacts. This can be overcome by use of high resolution synchrotron radiation CT because it has the ability of acquiring images with spatial resolution of more than 10 fold higher than that of modern CT scanners (19)(20)(21). In this study, authors created patient-specific 3D printed coronary models with simulation of calcified plaques in the left coronary arteries and scanned the 3D printed models with a resolution of 0.019 mm using a range of beam energies between 30 and 50 keV.…”