Semi-permanent transcorneal filter support and in vivo surgical implantation technique for open-angle glaucoma treatment


Primary open-angle glaucoma is a progressive disease affecting nearly 60 million people worldwide which, if left untreated, can lead to optic nerve head damage and complete loss of sight. Current interventions include: pharmaceutical drops, laser surgery, shunts, and bleb; however, these methods provide insufficient long-term efficacy in intraocular pressure management. We developed a semi-permanent, implantable transcorneal duct as a new aid in the treatment of this disease. The duct, composed of an intracorneal stabilizing washer and hollow screw, creates an interface between the anterior chamber and the external environment, allowing for the outflow of excess aqueous humor. We discuss the fluid mechanics behind designing and implementing a filter material capable of preventing the ingress of bacteria and viruses while modifying aqueous humor outflow resistances to pre-glaucomatous levels, finding the effective radius of such a material to be 10.44 μm. After performing surgical implantation in four rabbit eyes, subsequent testing showed successful integration between the screw and washer. Colored saline injections highlighted fluid flow progression out of the eye through the duct, suggesting that the device may be a viable approach to treating high intraocular pressure created by open-angle glaucoma.

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This study was partially supported by the Center for Implantable Devices (CID) at Purdue University and a grant from Bionode LLC. The authors would also like to acknowledge the contributions of Jay Shah and Rachael Swenson for providing invaluable manuscript feedback, as well as the expertise of surgical technician Curtis Slaubaugh.

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. All procedures performed in studies involving animals were in accordance with the ethical standards of the institution or practice at which the studies were conducted (PACUC Protocol #1309000929).

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Correspondence to Brett Collar.

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Collar, B., Simón, G., Yuan, Q. et al. Semi-permanent transcorneal filter support and in vivo surgical implantation technique for open-angle glaucoma treatment. Biomed Microdevices 21, 92 (2019).

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  • Glaucoma
  • Microfluidic device
  • Filtration
  • Design
  • Surgery