A novel device for the measurement of intraocular pressure, ocular rigidity and pulsatile blood flow.

Purpose Several instruments and methods are applied for the non invasive measurement of intraocular pressure, ocular rigidity and pulsatily blood flow. Most of this instruments and methods are based on the deformation force‐area principle. The purpose of this study was to present a novel device for the measurement of intraocular pressure, ocular rigidity and pulsatily blood flow. Methods The device consists of an opto‐mechanical head comprising a deformation sensor and a force sensor, a camera and a microstepping motor. The deformation sensor is an optoelectronic device consisting of two beamsplitters a plano‐convex lens, an illuminating fiber and a receiving fiber. Eighty three eyes were enrolled in a preliminary study, the intraocular pressure was measured with the novel device followed by a Goldman applanation tonometer measurement. Results The average IOP measured by the device was 17 (std 5.38) mmHg and the average rigidity coefficient was 0.01013 (std 0.039)μl‐1, the IOP measured by the GAT was 13.9 (std 3.23) mmHg. The statistical analysis indicated a significant statistical difference (p=9*10‐8) between the two devices. Conclusion Significant errors of the measurement are related to the centration of the optical head and the hand driven indentation. To overcome these limitations the device was upgraded with the addition of a coaxial camera for centration control and a microstepping motor for the applanation movement. An investigation of the accuracy and repeatability of the system with these new additions is underway.