A novel three-dimensional printed device to improve the safety of trocar insertion in hypotonous eyes

The force required for trocar insertion in hypotonous eyes can cause significant deformation of the globe and result in an iatrogenic injury to the lens, posterior capsule, or retina from the sharp trocar tip. We developed a device designed to stabilize the globe and provide counterpressure without significant globe deformation during trocar insertion. Our novel device was modeled using computer-aided design software, three-dimensional (3D) printed, and validated in an ex vivo porcine model. The risk of trocar-retinal touch was evaluated by comparing the distance between the trocar tip and opposing retina with either a cotton swab or our 3D printed device. We found an increased distance between the retina and trocar tip at the time of trocar insertion using our novel device: 3.3 ± 1.3 mm (P = 0.035), suggesting an improved safety margin. This device has the potential to improve the safety of trocar insertion in eyes at risk of trocar-associated injury, including hypotonous, previously vitrectomized, and nanophthalmic eyes.