Blepharo-Tensiometer: New Eyelid Pressure Measurement System Using Tactile Pressure Sensor

Purpose: To assess a newly developed eyelid pressure measurement system called a blepharo-tensiometer that uses a tactile pressure sensor. Methods: The tactile sensor was 10 mm in diameter and approximately 0.4 mm thick. The sensor was covered with silicon rubber and was placed between a soft contact lens on the cornea and the inner surface of the eyelid. Under these conditions, the sensor measured the pressure of the eyelid on the ocular surface. The pressure of the upper and lower eyelids were measured separately while the eyelids were closed for at least 5 seconds in 34 eyes of 34 normal volunteers. To determine the reliability of the blepharo-tensiometer, the pressures of the upper and lower eyelids were measured on 3 separate days in both eyes of 12 normal volunteers. The correlation between the age and the eyelid pressure was calculated. Results: The intraclass correlation coefficients for the 3 measurements ranged from 0.675 to 0.911 for the upper eyelid and 0.663 to 0.925 for the lower eyelid. The mean eyelid pressure was 16.95 +/- 6.08 mm Hg for the upper lid and 16.11 +/- 7.27 mm Hg for the lower lid. The eyelid pressure decreased with increasing age, and both the upper and lower eyelid pressures were significantly and negatively correlated with age (upper eyelid pressures, P < 0.0001;lower eyelid pressures, P=0.000432). No complication was detected after the measurements in all of the subjects. Conclusions: Our blepahro-tensiometer can obtain repeatable measurements of the eyelid pressure and can be used to evaluate the pressure of the eyelids on the ocular surface in normal and diseased eyes