Matthew A Powers1, Malik Y Kahook2. 1. From the Department of Ophthalmology, University of Colorado School of Medicine, Aurora, Colorado, USA. 2. From the Department of Ophthalmology, University of Colorado School of Medicine, Aurora, Colorado, USA. Electronic address: malik.kahook@ucdenver.edu.
Abstract
PURPOSE: To describe the evolution of a new device to facilitate continuous curvilinear capsulorhexis (CCC) creation. SETTING: Department of Ophthalmology, University of Colorado School of Medicine, Aurora, Colorado, USA. DESIGN: Experimental study. METHODS: Bench-side ex vivo testing of unique prototypes for guidance and assistance of CCC in bovine and human eyes was performed. Five designs were sequentially tested as follows: a flexible circular blade of nickel-titanium alloy (nitinol), a flexible nitinol guide wire, a flexible elastomeric suction device, a combination approach of a nitinol guide wire and flexible silicone ring, and a freestanding micropatterned silicone ring. RESULTS: The first 3 designs were not amenable to insertion through a sub-2.4 mm corneal incision and failed to maintain adequate downward force to cut the capsule and/or prevent radial tears. The fourth design was successfully inserted through a 2.4 mm incision and maintained adequate downward pressure and contact to guide a manual CCC without radial tears. The final design was insertable through a 2.4 mm incision and exhibited self-adhesive characteristics after placement on the anterior capsule of an ophthalmic viscosurgical device-filled anterior chamber. CONCLUSIONS: Given the steep learning curve of manual capsulorhexis and the high cost of capsulotomy-assistive devices, such as the femtosecond laser, an alternative approach for creating a CCC is desirable. Performance of a highly precise manual CCC through a small incision using a medical-grade silicone device with an adhesive micropatterned design is a viable and cost-effective option for use in cataract surgery across a wide range of user experience. FINANCIAL DISCLOSURE: All authors are named as the inventors in a patent filed by the University of Colorado covering the details in this report.
PURPOSE: To describe the evolution of a new device to facilitate continuous curvilinear capsulorhexis (CCC) creation. SETTING: Department of Ophthalmology, University of Colorado School of Medicine, Aurora, Colorado, USA. DESIGN: Experimental study. METHODS: Bench-side ex vivo testing of unique prototypes for guidance and assistance of CCC in bovine and human eyes was performed. Five designs were sequentially tested as follows: a flexible circular blade of nickel-titanium alloy (nitinol), a flexible nitinol guide wire, a flexible elastomeric suction device, a combination approach of a nitinol guide wire and flexible silicone ring, and a freestanding micropatterned silicone ring. RESULTS: The first 3 designs were not amenable to insertion through a sub-2.4 mm corneal incision and failed to maintain adequate downward force to cut the capsule and/or prevent radial tears. The fourth design was successfully inserted through a 2.4 mm incision and maintained adequate downward pressure and contact to guide a manual CCC without radial tears. The final design was insertable through a 2.4 mm incision and exhibited self-adhesive characteristics after placement on the anterior capsule of an ophthalmic viscosurgical device-filled anterior chamber. CONCLUSIONS: Given the steep learning curve of manual capsulorhexis and the high cost of capsulotomy-assistive devices, such as the femtosecond laser, an alternative approach for creating a CCC is desirable. Performance of a highly precise manual CCC through a small incision using a medical-grade silicone device with an adhesive micropatterned design is a viable and cost-effective option for use in cataract surgery across a wide range of user experience. FINANCIAL DISCLOSURE: All authors are named as the inventors in a patent filed by the University of Colorado covering the details in this report.