Development of an Eye Model Using 3D-Printing for Correlating Measured Intraocular Pressure with Actual Internal Pressure

PURPOSE: The aim of this study was to develop a 3D-printed eye model to simulate measuring intraocular pressure (IOP) as a training device, and to assess the correlation between measured IOP using common clinical techniques and actual internal pressure. METHODS: The IOP eye model was designed using CAD software and printed with a resin stereolithography (SLA) 3D-printer (Formlabs 3B, Formlabs Inc., MA, USA). Two clinical instruments, Tono-pen (Tono-Pen AVIA, Reichert Ophthalmic Instruments, USA), and Perkins hand-held tonometer (Clement Clarke Perkins Tonometer Mk2, Vision Equipment Inc., USA) were used for IOP measurements of the model. The pressure within the model was adjusted between 7 to 55 mmHg at 5 mmHg increments, and the IOP values of the tonometry were correlated to the internal pressure displayed on the gauge. RESULTS: The IOP model could reliably produce internal pressure from 0 to 56 mmHg. The results showed that the Tono-pen measurements above 7 mmHg were closely correlated to the internal pressure obtained from the pressure gauge (Pearson r = 0.99, p < 0.0001). However, aligning the mires and measuring IOP accurately with the Perkins device was challenging. CONCLUSION: The 3D-printed eye model was able to strongly correlate IOP readings taken with a Tono-pen with internal pressure measured by a pressure gauge. The internal pressure of this model can be regulated and is envisioned as a potential model for practicing tonometry at different ranges of pressure.