title: Review of the Development of Methods for Characterization of Microspheres for Use in Embolotherapy: Translating Bench to Cathlab.
abstract: Therapeutic embolotherapy is the deliberate occlusion of a blood vessel within the body, which can be for the prevention of internal bleeding, stemming of flow through an arteriovenous malformation, or occlusion of blood vessels feeding a tumor. This is achieved using a wide selection of embolic devices such as balloons, coils, gels, glues, and particles. Particulate embolization is often favored for blocking smaller vessels, particularly within hypervascularized tumors, as they are available in calibrated sizes and can be delivered distally via microcatheters for precise occlusion with associated locoregional drug delivery. Embolic performance has been traditionally evaluated using animal models, but with increasing interest in the 3R's (replacement, reduction, refinement), manufacturers, regulators, and clinicians have shown interest in the development of more sophisticated in vitro methods for evaluation and prediction of in vivo performance. Herein the current progress in developing bespoke techniques incorporating physical handling, fluid dynamics, occlusive behavior, and sustained drug elution kinetics within vascular systems is reviewed. While it is necessary to continue to validate the safety of such devices in vivo, great strides have been made in the development of bench tests that better predict the behavior of these products aligned with the principles of the 3R's.
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, University Road, Highfield, Southampton, SO17 1BJ, UK.|Biocompatibles UK Ltd., Lakeview, Riverside Way, Watchmoor Park, Camberley, GU15 3YL, UK.
authors.forename: Marcus
authors.initials: M
authors.lastname: Caine
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, University Road, Highfield, Southampton, SO17 1BJ, UK.
authors.forename: Dario
authors.initials: D
authors.lastname: Carugo
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, University Road, Highfield, Southampton, SO17 1BJ, UK.
authors.forename: Xunli
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Faculty of Engineering and the Environment, University of Southampton, University Road, Highfield, Southampton, SO17 1BJ, UK.
authors.forename: Martyn
authors.initials: M
authors.lastname: Hill
authors.affiliation: Biocompatibles UK Ltd., Lakeview, Riverside Way, Watchmoor Park, Camberley, GU15 3YL, UK.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Dreher
authors.affiliation: Biocompatibles UK Ltd., Lakeview, Riverside Way, Watchmoor Park, Camberley, GU15 3YL, UK.
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Lewis
mesh_terms: D000818:Animals; D004621:Embolization, Therapeutic / Q000379:methods*; D006801:Humans; D008863:Microspheres
keywords: drug-eluting bead; embolization; microsphere; performance testing