A 3D-Printed Aqueous Drainage Tube with an Expandable Inner Diameter to Accommodate the Intraocular Pressure (IOP) Fluctuations After Glaucoma Surgery.

Glaucoma treatment involves reducing the intraocular pressure (IOP), which can damage the optic nerve, to a normal range. Aqueous drainage devices may be used for treatment, and a variety of devices have been proposed. However, they have a non-variable and uniform inner diameter, which makes it difficult to accommodate the IOP fluctuations that occur after glaucoma surgery. To ensure effective treatment in the early post-operative period with low IOP and the late post-operative period with high IOP, the inner diameter should be expandable over time to allow for smooth aqueous drainage. Here, we applied 3D printing technology with a tri-axial nozzle to develop an aqueous drainage tube that can expand its inner diameter. The distinct bilayer structure of the device allows it to expand its inner diameter through biodegradation, which can accommodate the IOP fluctuations that often occur after glaucoma surgery. The fabricated structure was evaluated in a series of tests, including leakage, cytotoxicity, and degradation experiments. The device did not show any leakage, was not toxic to cells, and demonstrated the expansion of the inner diameter through biodegradation. The device may provide a more effective post-operative solution for glaucoma patients by alleviating the effects of low IOP in the early post-operative period and high IOP in the late post-operative period.