Biodegradable Anti-Stenosis Microsurgical Implantable Hydrogel Stent for Efficient Vas Deferens Recanalization

Abstract

Vasovasostomy is a surgical procedure aimed at restoring male fertility, whereas low anastomotic efficiency, delayed healing, and postoperative stenosis are key problems encountered during vas deferens recanalization. Here, a directly coaxial-printable and robust PCB hydrogel stent is designed to enhance the effectiveness of vasovasostomy by photo-polymerizing host–guest complexations between poly(ethylene glycol) methyl ether acrylate and α-cyclodextrin acrylate, using N, N’-bis(acryloyl)cystamine as a degradable crosslinker. The PCB hydrogel exhibits continuous micro-stent fabrication capabilities and exceptional anti-deformation mechanical properties (elastic modulus, fracture strength, and toughness of 1.3 MPa, 2.5 MPa, and 480.4 kJ·m⁻³, respectively) due to the formation of a polypseudorotaxane threading network integrated with nano-self-assembled structures. Rabbit microsurgical vasovasostomy experiments demonstrate that the time required for tissue anastomosis is reduced by more than half with the support of the PCB hydrogel. Moreover, the stent's excellent resistance to cell adhesion and complete degradability within 28 days in vivo effectively prevents stenosis and promotes healing of the vas deferens, achieving a 100% patency rate. This high-performance PCB stent presents a promising solution for effective vas deferens-related treatment and various other applications.