3D bioprinting in airway reconstructive surgery: A pilot study

Area of Science:

• Regenerative Medicine
• Biomaterials Engineering
• Surgical Innovation

Background:

• Congenital subglottic stenosis is a rare laryngeal anomaly requiring surgical intervention.
• Anterior laryngotracheal reconstruction (LTR) using autologous rib grafts is a common surgical approach.
• 3D printing offers potential for creating patient-specific surgical scaffolds.

Purpose of the Study:

• To evaluate the in vivo performance of 3D printed Polycaprolactone (PCL) scaffolds for anterior laryngotracheal reconstruction (LTR) in an ovine model.
• To assess the biocompatibility and integration of PCL scaffolds seeded with mesenchymal stem cells.
• To explore the feasibility of 3D printed bioconstructed grafts for treating congenital subglottic stenosis.

Main Methods:

• 3D computer-aided design and additive manufacturing were used to create PCL scaffolds.
• Scaffolds were seeded with autologous mesenchymal stem cells and cultured in vitro.
• Anterior LTR was performed on five sheep using the prepared scaffolds, followed by endoscopic and histopathological evaluation.

Main Results:

• Two sheep demonstrated successful scaffold integration and respiratory epithelium growth after 6 months.
• Two sheep experienced respiratory distress due to poor graft integration, necessitating early sacrifice.
• One sheep developed a wound abscess, indicating poor scaffold integration and inflammation.

Conclusions:

• Excessive material stiffness of PCL and ovine anatomical features pose limitations for scaffold integration.
• Future bioconstructed grafts should be more flexible and elastic for enhanced tissue integration.
• 3D printed grafts hold promise for simplifying complex laryngotracheal stenosis surgeries.