On-Demand 3D Print Mechanically Adaptive Lacrimal Bypass Tube Implants

Artificial lacrimal bypass tube (LBT) implantation has been widely used for treating proximal lacrimal drainage obstruction. However, its long-term clinical success is still constrained by the frequent tube dislodgement due to the mismatch mechanical properties to surrounding soft tissue and poor tissue fusion along its smooth surface. Aiming to tackle this challenge, here a method of 3D printing LBT is reported that comprises three key features: 1) mechanical adaptability to match with the characteristics of surrounding soft tissue, 2) tailorable surface porosity to promote tissue binding, and 3) customization to accommodate individual patient's anatomies. Using hydrogel-based biocompatible ink, LBTs are 3D printed that are initially rigid (compressive Young's moduli E: ≈1.6 GPa) for the ease of surgical insertion but become compliant (E: 0.16–3.36 MPa) after implantation to better match with the surrounding tissue. The inherent manufacturing flexibility of 3D printing enables integration of the LBT and porous shell to prompt tissue infusion to ensure its mechanical integrity. Ultimately, in vivo intramuscular and orthotopic implantation studies demonstrate that the LBTs exhibit excellent tolerance in rabbits with minimal inflammation observed, and the porous shells help to significantly reduce the dislocation rate from 80% to 13.3%.