Intraocular pressure is usually measured by applying a force on the cornea using a tonometer. Although sufficiently accurate, tonometers are only used in ophthalmologist offices and so don’t measure intra-day pressures. They also fail with people post cataract surgery that have a thicker cornea. Researchers at University of Arizona have developed a new device that measures intraocular pressure through the eyelid.
The self-test instrument has been designed in Eniko Enikov’s lab at the UA College of Engineering. Gone are the eye drops and need for a sterilized sensor. In their place is an easy-to-use probe that gently rubs the eyelid and can be used at home.
“You simply close your eye and rub the eyelid like you might casually rub your eye,” said Enikov, a professor of aerospace and mechanical engineering. “The instrument detects the stiffness and, therefore, infers the intraocular pressure.” Enikov also heads the Advanced Micro and Nanosystems Laboratory.
While the probe is simple to use, the technology behind it is complex, involving a system of micro-force sensors, specially designed microchips, and math-based procedures programmed into its memory.