Direct, accurate, and continuous intraocular pressure (IOP) monitoring is necessary to better understand the relationship between elevated IOP and glaucoma, a degenerative eye disease. Currently, tonometry is used to measure IOP in research subjects. In this technique, the deflection of the cornea due to a known applied force is measured and IOP values are derived based on the invalid assumption that the corneas of all eyes are very similar. Tonometry is highly operator dependent, labor intensive and can be stressful to research animals, particularly if a study calls for several daily measurements. This thesis describes the development of a wireless, implantable pressure sensor that can overcome these drawbacks of traditional IOP monitoring. Design, fabrication and characterization of the Parylene-based sensor are presented with the aim of enabling 1-2 year studies on the relationship between IOP and glaucoma. The sensor is comprised of an integrated planar MEMS coil and a capacitive pressure sensing element. Parylene-C was chosen as the packaging and structural material due to its flexibility and performance as a moisture and dielectric barrier. Sensors were evaluated for sensitivity and telemetry distance in an environment approximating the anterior chamber of the eye. Experimental results demonstrate wireless pressure sensing capability with 1 mmHg resolution over the range of 0-100 mmHg in isotonic saline at a telemetry distance of 20 mm.
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