Measurement of the tear film and anterior chamber by confocal microscopy

Abstract

We report on the development of a novel, low cost instrument that is capable of accurately measuring small, short and long term changes in the thickness of the cornea and tear film at high speed. The performance of the instrument was tested by measuring the influence of Allergan's OPTIVE™ lubricating eye drops on the thickness of the cornea and tear film. Comparative measurements to quantify the performance were taken using Haag-Streit's LenStar. It was found that the newly developed instrument accurately measured a change in thickness of around 9 µm with an accuracy comparable to the LenStar, and with a standard deviation of less than 1 micrometer. Since the new instrument was not configured to resolve the tear film from the cornea, we are not yet able to distinguish the cause of the thickening.