Abstract
A new electromechanical method to measure intraocular pressure is presented. A light probe was made to collide with an eye (cornea or sclera) and to bounce back. The impact was registered by an acceleration sensor or the duration of contact with the eye was measured using the phenomenon of the electrical conductivity of biological objects. Laboratory experiments were carried out using pig eyes pressurized with water leveled to different heights. Preliminary clinical trials were carried out comparing the values obtained with those of the Goldmann applanation tonometer. The time of contact and the deceleration time decreases and the deceleration maximum increases in proportion with IOP. A new kind of tonometer can be constructed based on this principle. Measurement can be performed to cornea or sclera without an anesthetic drop. Further study is required to evaluate the accuracy and usefulness of this method.
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Abbreviations
- ADC:
-
analog to digital converter
- g:
-
the earth's gravitation force (9.8 m/s2)
- IOP:
-
intracular pressure
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Kontiola, A. A new electromechanical method for measuring intraocular pressure. Doc Ophthalmol 93, 265–276 (1997). https://doi.org/10.1007/BF02569066
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DOI: https://doi.org/10.1007/BF02569066