Advances in Biomaterials and Technologies for Vascular Embolization

Abstract

Minimally invasive transcatheter embolization is a common nonsurgical procedure in interventional radiology used for the deliberate occlusion of blood vessels for the treatment of diseased or injured vasculature. A wide variety of embolic agents including metallic coils, calibrated microspheres, and liquids are available for clinical practice. Additionally, advances in biomaterials, such as shapememory foams, biodegradable polymers, and in situ gelling solutions have led to the development of novel pre-clinical embolic agents. The aim here is to provide a comprehensive overview of current and emerging technologies in endovascular embolization with respect to devices, materials, mechanisms, and design guidelines. Limitations and challenges in embolic materials are also discussed to promote advancement in the field.

A versatile UCST-type composite microsphere for image-guided chemoembolization and photothermal therapy against liver cancer

“…S1I †), which were comparable to the loading capacity of commercial microspheres. 9,10 As platforms designed with a thermal-triggered release property, the cumulative release of DOX from P(AAm-co-AN) and P(AAm-co-AN)/(SPION@PDA) microspheres at 37°C after 7 days were only 3.85% and 3.05%, respectively, indicating the good storage stability of these drug-loaded microspheres (Fig. 3E).…”

“…6,7 Therefore, the performance of the chemoembolization vectors is the key determinant of TACE outcome. [8][9][10] The major goal of TACE is to achieve complete tumor necrosis, thus providing patients with survival benefits as much as possible. It has been demonstrated that the magnitude of tumor necrosis, in terms of treatment response which is usually assessed by contrast enhanced imaging studies, correlated closely with prognosis.…”

“…DEB release per loaded drugs via ion-exchange mechanism in a slow and sustained release pattern to deliver chemotherapeutic agents toward tumor lesions continuously. [8][9][10] However, being intrinsically drug-resistant in nature, liver cancer is notorious for being refractory to either systemic or transarterial infusion chemotherapy. 4,16 Furthermore, conclusive evidence supporting the superiority of TACE over transarterial embolization (TAE) is still absent, suggesting the poor performance of chemotherapy for liver cancer.…”

Relevance of Porcine Stroke Models to Bridge the Gap from Pre-Clinical Findings to Clinical Implementation

“…The main method to achieve endovascular embolization of arteries in pigs has been the injection of autologous blood clots to extracranial vessels [ 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 ]. The embolization of an artery implies the reduction of its blood flow [ 142 ]. For instance, bilateral thromboembolism to reduce blood flow in both ascending pharyngeal arteries caused multiple and variable focal areas of stroke damage, although consistent temporo-parietal infarcts were not generated as seen by diffusion-weighted imaging [ 127 ].…”

Stiffness Self‐Tuned Shape Memory Hydrogels for Embolization of Aneurysms

“…[ 5 ] To solve the problems, a variety of modified coils have been proposed, such as Cerecyte Coils, Axium Detachable Coil system, Matrix and Matrix2 Detachable Coils, HydroCoil, and HydroSoft. [ 6–11 ] Among them, the hydrogel coated coils were designed mainly to increase the packing density by using a hydrogel coating that expanded in the presence of blood. [ 12 ] Although excellent packing density of 64–85% was achieved by hydrogel‐coated coils, the early gel expansion and concurrently increased friction make it difficult for the clinician to deploy the modified coils.…”