Non–invasive Interference Tear Meniscometry Using Tearscope–plus in Dry Eye Patients

Abstract

Abstract: : Purpose:Recently measurement of tear meniscus has been considered to be important reflecting tear reservoir volume. Meniscus height measurement using instillation of fluoresecein solution or non–invasive meniscus radius measurement has been investigated. In the present study, using commercially available Tearscope interference devise (Windsor, UK), non–invasive measurement of tear meniscus height (TMH) was applied to dry eye subjects. Methods:Tearscope–plus light source was set at the slitlamp. Tear interference image could be observed as well as tear meniscus non–invasively when focusing at lid margin. Interference image of lower tear meniscus was recorded using high quality CCD camera and image filing system in JPEG format. Tear meniscus height was measured using ImageJ 1.32 image analysis software (distributed by NIH, US). Sixteen eyes from 8 normal subjects and 14 eyes from 7 dry eye subjects were measured. Also change of TMH after the punctual occlusion was investigated in 5 eyes of 3 severe dry eye subjects. Results: Lower TMH was 0.14 ± 0.03 mm in normal subjects and 0.24 ± 0.06 mm in dry eye subjects, respectively (P < 0.0001) After the punctal occlusion, lower TMH changed from 0.09 ± 0.04 mm to 0.27 ± 0.01 mm significantly (P = 0.0007) Conclusions: Our method could non–invasively observe and measure tear meniscus height. It was significantly lower in dry eye subjects, and also significantly improved after punctal occlusion procedure. This method is expected to be helpful in diagnosis of dry eye and evaluation of treatment efficacy.

Keywords: cornea: tears/tear film/dry eye • cornea: clinical science