METHOD AND DEVICE FOR MONITORING BIOMECHANICAL PROPERTIES OF THE EYE

摘要

A contact lens shaped measuring device (1) comprises sensor (3) having a protrusion (14) towards the cornea (22). The measuring device (1) is flexible to a degree that it is flattened by a closing eye lid and the protrusion creates an indentation of the cornea. The occurring force on the protrusion is measured by the sensor. Applying a constant lid acceleration/deceleration model to the movement of the lid and a mechanical model to the cornea, the tension of the cornea is determined and deduced from the force measured with the lid closed, yielding the true intraocular pressure. In an alternative, the protrusion is characterized by a discontinuity in its shape, or the sensor is subdivided, each subsensor being characterized by a protrusion of different shape. With the values obtained as extrema and at the discontinuity or with different protrusions, the cornea tension can be obtained by a (linear) extrapolation.

主权项

1. A method for monitoring biomechanical properties of the eye, using a measuring arrangement which comprises a measuring device designed to be born in the manner of a contact lens, the measuring device comprising a force detector in operative engagement with a protrusion directed towards the cornea of an eye once the measuring device is applied to the eye, the measuring device being flexible in order to be pressed against the cornea by a lid of the eye moving over the measuring device, wherein the method comprises the following steps:
measuring and storing force values and indication of time when the force values occurred; determining the time tstart when the force values start to be significantly greater than zero, time tstop at which the force values after tstart are no more substantially greater than zero, equivalent to the times when the protrusion first gets in contact with the cornea respectively disconnects therefrom; determining a maximum force value between tstart and tstop in order to determine the phases of eye closing, eye being closed, and eye opening; deriving from the force values and the corresponding time values between tstart and tEnd a value indicative of the tension of the cornea.