Highly elastic polyvinyl alcohol embolic microspheres for effective transarterial embolization†

Abstract

Transarterial embolization therapy is a highly promising, minimally invasive interventional procedure for treating vascular and neoplastic diseases in the clinic. The use of highly elastic and deformable embolization microspheres is crucial for ensuring smooth delivery through a catheter and achieving complete endovascular embolization. In this study, a polyvinyl alcohol embolic microsphere, MegaSphere, with exceptional elasticity was used for vascular embolization. The results obtained from an in vitro embolization model demonstrated the good stability and elastic deformation ability of MegaSphere. These properties allow these spheres to aggregate tightly and effectively embolize blood vessels at different levels. Furthermore, in a rabbit model, we achieved highly efficient renal embolization via MegaSphere. These microspheres could reach the distal vessels of the renal artery and effectively embolize small arteries within the renal cortex, resulting in complete terminal embolization. Substantial necrosis of the renal parenchyma was observed within seven days after embolization, indicating an excellent embolization effect. Moreover, in a rabbit model with liver VX2 transplant tumors, the use of drug-loaded MegaSphere-doxorubicin microspheres demonstrated strong efficacy in antitumor chemoembolization therapy. Through blockade of the tumor blood supply and increased local chemotherapy, effective inhibition of liver tumor progression was achieved within seven days following transcatheter arterial chemoembolization (TACE). In conclusion, this study highlights the promising potential of MegaSphere as an embolic agent with potential for clinical translational applications.