3:27 PM Abstract No. 305 Vascular selectivity of radiopaque beads during transarterial embolization

Abstract

To determine if LUMI bead size, injection rate, or concentration affects the ability to embolize blood vessels further into the periphery of the organ. A total of 9 Yorkshire pigs underwent fluoroscopy-guided injection of LUMI radiopaque beads using 2 different LUMI bead sizes (R0 = 40-90 and R1 = 70-150 microns). Each animal was injected with 1 of 3 bead/Visipaque320 contrast concentrations (1:4, 1:9, and 1:14) and at 1 of 3 injection rates (0.5 mL/min, 1.0 mL/min, and 1.5 mL/min). Isovue contrast was used to position the catheter and allow for direct injection of the embolization beads into the arterial branch of the liver and kidneys. The R1 and R0 beads were used to embolize the left kidney and left hepatic lobe and the right kidney and right hepatic lobe, respectively. The animals were subsequently euthanized. The distance of the beads from the hilum and the capsule was then evaluated with imaging and pathological correlation. Technical success rate was 100% (36/36). Embolization was achieved regardless of the injection rate and concentration. The complication rate after the embolization process was 0% (0/36). In the liver, the beads traveled more distally from the hilum for lower concentrations (P = .008), but this was not statistically significant for the kidney (P = .279). When comparing the distance traveled by the beads from the hilum with changes in the injection rate, the difference was not statistically significant for the liver or kidney (P = .985 and P = .907, respectively). When comparing the distance traveled by the beads from the hilum with changes in the bead size, the difference was not statistically significant for the liver or kidney. (P = .779 and P = .244, respectively). However, in the kidney, when measuring the distance from the beads to the capsule, lower bead sizes demonstrated greater peripheral distribution (P = .007). Lower concentrations and smaller bead sizes appear to demonstrate a more peripheral distribution, although this may be organ dependent. However, bead distribution does not appear to be affected by injection rate.