Achieving clinically viable 12-CM readout distance from micromachined implantable intraocular pressure sensor using a standard clinical slit lamp

Achieving a practical readout distance for implantable intraocular pressure (IOP) sensors is an essential step toward commercialization yet has remained as a major challenge. Using the Zeiss SL-30 slit lamp — a standard ophthalmic scope widely used by clinicians, we have demonstrated an optical readout distance of 12 cm from a micromachined IOP sensor implanted in an ex-vivo rabbit eye. We show that we have achieved this readout distance by (1) redesigning the sensing area of the IOP sensor and its fabrication steps to significantly improve the signal-to-noise ratio; and (2) incorporating a novel robust detection algorithm, which includes a much-improved opto-mechanical model, that allows us to remove the background noise and instantaneously map the sensor's optical signal to the corresponding IOP value. A significant increase in readout distance accomplished using a well established ophthalmic clinical scope makes our IOP system a more clinically viable choice.