Initial investigations on systems for measuring intraocular pressure

Basic investigations on an intraocular implant system for continuous measurements of the intraocular pressure (IOP) are introduced. The system consists of a pressure sensor connected to transponder components integrated in the haptic of an artificial soft intraocular lens. External transponder components will he integrated in a spectacle and a hand-held unit. The influence of the lens material on the pressure sensor performance will be discussed in detail. Two pre-version of the concept mentioned will be introduced. In the first version, a pressure sensor was connected to a microwire. In a second version, the sensor was connected to transponder components for wireless data and energy transmission. Both versions were encapsulated in standard soft intraocular lens material. Pressure measurements show the same sensitivity before and after encapsulation. In addition, a small offset was observed due to the influence of the silicone coating. The performances of the sensors have the same precision as widely accepted gold standard for the determination of the IOP. (C) 2000 Elsevier Science B.V. All rights reserved.