Integrated 3D bioprinting-based geometry-control strategy for fabricating corneal substitutes

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Biofabrication

Background:

• Global donor cornea shortage necessitates urgent development of artificial alternatives.
• Existing tissue-engineered cornea substitutes face challenges in clinical application, particularly in achieving patient-specific curvature.
• Limitations include difficulties in designing curvature to match the bulbus oculi.

Purpose of the Study:

• To present an integrated 3D bioprinting strategy for fabricating customized cornea substitutes.
• To overcome limitations of existing artificial cornea substitutes by enabling design, customized fabrication, and evaluation of complex structures.
• To create multi-layer hollow structures with complicated surfaces for improved corneal replacement.

Main Methods:

• Integrated three-dimensional (3D) bioprinting system combining digital light processing (DLP) and extrusion bioprinting.
• Personalized corneal substitute design using mathematical modeling and computed tomography (CT) scans of natural corneas.
• Evaluation of printed corneal substitutes through biomechanical analysis, weight, structural integrity, and fit assessment.

Main Results:

• Successful fabrication of high water content, highly transparent curved films mimicking natural human cornea geometry.
• Demonstrated a rapid, simple, and low-cost manufacturing process with high repetition rate and quality.
• Achieved geometric features designed according to natural human cornea specifications.

Conclusions:

• Feasibility of customized design, analysis, and fabrication of corneal substitutes demonstrated.
• The programmability of the method allows for potential production of other cornea-like shell structures.
• Opens possibilities for fabricating substitutes for structures like the glomerulus, atrium, and oophoron.