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arXiv · 1710.09023

Near-infrared laser thermal conjunctivoplasty

Jianlong Yang·Rahul Chandwani Varun Gopinatth·Timothy Boyce·Stephen Pflugfelder·David Huang·Gangjun Liu
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Abstract

Conjunctivochalasis is a common cause of tear dysfunction due to the conjunctiva becoming loose and wrinkly with age. The current solutions to this disease include either surgical excision in the operating room, or thermoreduction of the loose tissue with hot wire in the clinic. We developed a near-infrared (NIR) laser thermal conjunctivoplasty (LTC) system, which gently shrinks the redundant tissue. The NIR light is mainly absorbed by water, so the heating is even and there is no bleeding. The system utilizes a 1460-nm programmable laser diode system as a light source. A miniaturized handheld probe delivers the laser light and focuses the laser into a 10x1 mm2 line. A foot pedal is used to deliver a preset number of calibrated laser pulses. A fold of loose conjunctiva is grasped by a pair of forceps. The infrared laser light is delivered through an optical fiber and a laser line is focused exactly on the conjunctival fold by a cylindrical lens. Ex vivo experiments using porcine eye were performed with the optimal laser parameters. It was found that up to 50% of conjunctiva shrinkage could be achieved.

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Jianlong Yang, Rahul Chandwani Varun Gopinatth, Timothy Boyce, Stephen Pflugfelder, David Huang, Gangjun Liu. 2017-10-25. Near-infrared laser thermal conjunctivoplasty. https://arxiv.org/abs/1710.09023

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