"Imageable" Zinc-Silicate Glass Microspheres For Transarterial Embolization: A Renal Artery Embolization Study.

Sharon Kehoe, Salma Amensag, Mark Looney, Robert J. Abraham,  and Daniel Boyd
  • 1 ABK Biomedical Inc. 1344 Summer Street, Suite 212, Halifax, B3H0A8
  • 2 Department of Applied Oral Sciences, Dalhousie University, PO Box 15000, Halifax, NS, Canada, B3H 4R2
  • 3 School of Biomedical Engineering, Dalhousie University, PO Box 15000, Halifax, NS, Canada, B3H 4R2
  • 4 Department of Diagnostic Imaging and Interventional Radiology, QE II Health Sciences Centre, Halifax, NS, Canada, B3H 3A7


Intrinsically radiopaque (imageable) microspheres for transarterial embolization (TAE) are required to enable real-time intraprocedural feedback and definition of spatial distribution patterns of embolic materials in target tissues. This pilot study evaluates acute and sub-chronic safety and efficacy of imageable zinc-silicate (Zn-Si) glass microspheres in a swine renal artery embolization (RAE) model. Eight swine were divided into two cohorts. Clinical determinants of embolization effectiveness, including imageability, deliverability and temporal/ spatial distribution of microspheres in target tissues were assessed. Subsequently, cohort I and II were used to evaluate the acute and subchronic host response against the Zn-Si microspheres versus a clinical control. The developed microspheres provide for direct intraprocedural feedback using standard diagnostic imaging techniques. Fluoroscopy correlated with ex-vivo high-resolution radiography, CT and micro-CT, demonstrating high imageability, excellent spatial distribution and packing of the Zn- Si microspheres. At follow-up, infarction of the embolized kidneys was noted without any major adverse tissue reaction. Mild recanalization was observed microscopically for both experimental and control microspheres. Zn-Si microspheres permit the definition of spatial distribution in a target tissue, consequently permitting the optimization, personalization and improvement of TAE techniques.

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Biomedical Glasses is an international open access journal covering the field of glasses for biomedical applications. The aim of the journal is to provide a peer-reviewed forum for the publication of original research reports and authoritative review articles related to the development of biomedical glasses and their use in clinical applications.