Embolic efficacy and safety profile of UniPearls® microspheres for hepatic artery embolization in domestic pigs

UniPearls^® is a novel product of microspheres developed recently with unique features. This study aimed to investigate the embolic efficacy and safety of UniPearls^® for hepatic artery embolization (TAE) in vivo. Eighteen domestic pigs were randomly allocated to experimental group (n = 9) or control group (n = 9) and subjected to TAE procedure [set as day (D) 1]. UniPearls^® (size: 70 μm) was applied in experimental group, whereas HepaSphere^® (size: 30-60 μm) was applied in the control group. Domestic pigs were euthanized on D3, D8, and D29 (n = 3 per group at each timepoint). The mean injection speed, volume, and delivery performance score were 0.43 mL/min, 0.86 mL, and 3 points (highest score) in the experimental group, respectively; in comparison, the injection speed was greater in the experimental group versus the control group, whereas the injection volume and delivery performance score were not different. The angiographic embolization score was greater in the experimental group compared to the control group on D3, instead of on D1, D8, or D29. HE staining revealed that: on D3 and D8, obvious embolic features were identified in both groups; however, on D29, vacuolization, defect, and lightening staining were found in control group, whereas intact margins and high staining were discovered in experimental group. Subsequent histological scoring also confirmed these findings. No off-target embolization, obvious adverse reactions, or deaths occurred in either group. Moreover, the majority of routine blood, biochemical, and coagulation indexes didn't differ between the two groups. UniPearls^® serves as a good choice for hepatic embolization with satisfied efficacy and safety profiles.