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Abstract #15937 Published in IGR 2-3
A resonator sensor for measurement of intraocular pressure: evaluation in an in vitro pig-eye model
Eklund A; Backlund T; Lindahl OAPhysiological Measurement 2000; 21: 355-367
Intraocular pressure (IOP) measurement is performed routinely at all eye clinics. High IOP, which can be a sign of glaucoma, can lead to degeneration of the retina and can cause blindness. In this study, the authors developed a resonator sensor for IOP measurement based on an oscillator consisting of a piezoelectric element made of lead zirconate titanate, a flat contact piece of nylon and a feedback circuit. The aim of the study was to evaluate the new sensor's ability to determine IOP in an in vitro pig-eye model. Six eyes from four pigs were removed and fixed in agar. They were then pressurized by a saline column (10-35 cm H2O) through a cannula inserted into the vitreous chamber. The IOP was measured with the resonator sensor applied to cornea. An Alcon applanation pneumatonometer and a standard Viggo-Spectramed pressure sensor connected to the saline column were used as references. The IOP as measured with the resonator sensor correlated well with the pressure elicited by the saline column for individual eyes (r = 0.96-0.99, n = 60) and for all eyes (r = 0.92, n = 360). The correlation between the resonance sensor and the pneumatonometer was r = 0.92 (n = 360). The pneumatonometer also showed a good correlation with the saline column (r = 0.98, n = 360). The authors conclude that their in vitro pig-eye model made it possible to induce reproducible variation in IOP, and measurement of that pressure with the newly developed resonator sensor gave very promising results for development of a clinically applicable IOP tonometer with unique properties.
Dr. A. Eklund, Department of Biomedical Engineering/Informatics, University Hospital of Umea, S-901 85 Umea, Sweden
Classification:
6.1 Intraocular pressure measurement; factors affecting IOP (Part of: 6 Clinical examination methods)
