Abstract
Conventional Yttrium-90 (Y-90) microspheres for Radioembolization are not directly visible on X-ray fluoroscopy or computed tomography (CT) precluding microsphere visualization at administration. We investigate the use of novel radiopaque microspheres for real-time X-ray and CT confirmation of tissue targeting. Intra-procedural CT region of interest (ROI) quantification of microsphere radiopacity may be translated to absorbed dose, allowing for personalized therapy. 30 μm (mean) diameter, multi-component, non-irradiated Y-89 glass microspheres were injected through a .021” microcatheter into the segmental arteries of the right and left kidneys of a hybrid farm pig. Fluoroscopy at time of injection and static X-ray and Cone-beam CT (CBCT) after embolization were obtained. After sacrifice, kidneys were explanted and imaged using fan beam CT (FBCT) and co-registered to CBCT. Average Hounsfield Units (HU) and voxel enhancement ratio (VER) data were obtained and analyzed (ANOVA, p<0.01) from spherical ROI’s placed on embolized (n=1) and non-embolized tissue (n=3) for CBCT and FBCT respectively. Real-time fluoroscopic and static x-ray visualization of microsphere delivery was confirmed. Three embolized parenchymal (microvasculature) ROIs with CBCT had mean voxel values from 191 to 229 HU. Non-embolized CBCT ROI had a mean value of 68 HU with VER of 2.8-3.4. Three embolized FBCT mean voxel values ranged from 80 to 107 HU, non-embolized FBCT ROI had a mean value of 34 HU with 2.4-3.2 VER. Embolized tissue ROIs had significantly greater voxel values than the non-embolized ROI for both CBCT (p<0.001) and FBCT (p<0.001). 3-dimensional HU threshold map data demonstrate the potential for CT based absorbed dose microsphere quantification. Novel radiopaque Y-90 Glass Microspheres demonstrate real-time fluoroscopic and static X-ray visualization and significant increase in tissue CBCT and FBCT radiopacity relative to non-embolized tissue with potential for tumor targeting, assessment of microsphere distribution and absorbed dose quantification.Tabled 1Parenchymal Tissue ROICBCT Mean (HU)CBCT Standard DeviationFBCT Mean (HU)FBCT Standard DeviationNon-embolized ROI68153411Embolized ROI 1217299624Embolized ROI 22294810742Embolized ROI 3191258019 Open table in a new tab
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
