Laser‐Responsive Shape Memory Device to Program the Stepwise Control of Intraocular Pressure in Glaucoma

• Published in: Advanced functional materials 2023-08, Vol.33 (35), p.n/a
• Main Authors: Lee, Kyubae, Choi, Wungrak, Kim, Si Yeong, Lee, Eon‐Bee, Oh, Won Take, Park, Jeongeun, Lee, Chan Hee, Lee, Jihei Sara, Bae, Hyoung Won, Jang, Dong‐Su, Lee, Kang Suk, Yi, Se Won, Kang, Mi‐Lan, Kim, Chan Yun, Sung, Hak‐Joon
• Format: Article
• Language: English
• Subjects: anti‐fibrotic drug release; Argon lasers; clinician‐specified control of intraocular pressure; computational fluid dynamics modeling; Fibrosis; Glaucoma; Hypertension; Intraocular pressure; Lasers; laser‐responsive shape memory polymers; Materials science; Shape memory
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202300264

There is an unmet need in the glaucoma clinic to control changes in the intraocular pressure (IOP), i.e., patient‐specific hypotony and tissue fibrosis‐mediated ocular hypertension, owing to the fixed tube diameter of the glaucoma drainage device. As a potential solution, the tube diameter can be adjusted, depending on the IOP, by shape memory polymer (SMP) and clinical laser systems, which can control the energy level, focus, and frequency by minimizing untargeted influences. To develop a translatable device, a laser‐responsive SMP with two additional elements: i) a tube with an intimal gel coating to release 5‐fluorouracil as an anti‐fibrotic drug and ii) a safety lock ring to block late hypotony in special cases is employed. When the SMP tube is inserted into a silicone tube and wrapped externally by the ring, intimal gel degradation and argon laser‐triggered diameter increase enable a three‐step IOP control. Sustained drug release of the intimal gel suppresses tissue fibrosis, and the ring prevents late hypotony by externally squeezing the silicone tube. The advanced design and functions are validated using computational in vitro and rabbit glaucoma models by determining clinic‐friendly argon laser parameters. Laser‐responsive shape memory polymer (SMP) device is designed to prevent hypotony and ocular hypertension through stepwise intraocular pressure control. With the insertion of the SMP tube into the silicone tube, early hypotony is prevented through an aqueous‐humor‐outflow decrease by a small inner tube diameter. Anti‐fibrotic drug release and argon laser‐triggered diameter expansion suppress ocular hypertension. Silicone tube wrapped by SMP+polycaprolactone ring, squeezed by argon laser shots, prevents late hypotony.