096 - Comparative Assessment of Distal Penetration between 40 micron Microspheres and a Novel Liquid Embolization Agent
Joshua Jones, PhD – Chief Scientist, Fluidx Medical; Jessica Karz, BS – Sr. Engineer, Fluidx Medical; Danny Smith, MS – Vice President, R&D, Fluidx Medical
Purpose: The GPX Embolic Device is a novel embolic agent designed for use in durable and pre-operative peripheral embolization procedures where there is intent for distal penetration. A recent clinical trial showed positive outcomes in many applications. This pre-clinical animal study compared the distal penetration of the GPX Embolic Device with 40 micron microspheres.
Material and Methods: Bilateral renal artery embolizations were performed in domestic swine. Six embolizations were performed using the GPX Embolic Device, with Embozene 40 micron beads used as the control device. Similarly sized vessels were chosen for each embolization, with sites selected after the 2nd or 3rd bifurcation of the renal artery. Each device was prepared consistent with its instructions for use prior to the embolization. Embolizations were then performed until stasis. Distal penetration of the embolization agents was evaluated using histopathology. The magnitude of occlusion of the arterial lumen of both the GPX material and Embozene beads was assessed based on the relative filling of the arterial lumen by the embolized material, and/or its proximate apposition to the arterial wall, and by the presence of residual red blood cells (RBCs) within the lumen of the treated artery.
Results: All embolizations with both agents were considered a technical success, defined as being fully occluded at the first follow-up angiogram ( < 1 minute after delivery). The GPX Embolic Material exhibited effective and thorough embolization throughout the renal cortical vasculature, including the smallest arteries/arterioles of the distal cortex (≤20 µm vessel diameter), and including the efferent arterioles of the afferent arterioles of the glomerulus and/or vasculature glomerular tufts. Microspheres were also observed in the renal cortical vasculature, but not in vessels ≤20 µm.
Conclusions: This study demonstrated the ability of the GPX Embolic Device to penetrate and occlude arterial vasculature ≤ 20μm in diameter, including the afferent arterioles of the glomerulus and within the glomerular vasculature. The 40µm microspheres used as the control device are the smallest commercially available microsphere embolization device and they did not penetrate into distal cortical arterial vasculature ≤ 20μm in this study. This study indicates that GPX is an embolization agent that may be well-suited for highly distal embolization applications.