Novel Light Intensity Device (LuxIQ) for Quantitative Evaluation of Dry Eye Disease.
H. Fishman1, P.G. Borden2, M. Klein2, 1Fishman Vision, Palo Alto, CA; 2Jasper Ridge Inc, Menlo Park, CA.
To evaluate the effectiveness of a novel device that quantifies light sensitivity in patients
reporting Dry Eye Disease (DED) symptoms, and whether light sensitivity measurement is an effective indicator of DED.
15 patients reporting DED symptoms were recruited during their regularly scheduled visit to a Dry Eye clinic. A routine screening exam was conducted, including Non-Invasive Tear Break-up Time (NIBUT), Schirmer strips, and Osmolarity. In addition, each patient was asked to adjust a device (LuxIQ™, Jasper Ridge Inc) to their preferred illuminance and white light color temperature on a 40-cm near vision chart (Colenbrander Mixed Contrast), over an illuminance range of 0-5000 lux and color temperature range of 2,700 to 6,500°K. Measurement was bilateral (both eyes open) Patients were not told the purpose of this measurement. 8 control subjects, who did not report DED symptoms, were also measured for illuminance and color temperature preference.
The average illuminance and color temperature for the DED patients was 1750±753 lux and 4507±784°K, and for the controls 2643±1435 lux and 5000±852°K (see figure 1). The DED distribution shows a strong peak between 1000 and 2000 lux, and is significantly lower than the control (p=.21). The NIBUT, Schirmer and Osmolarity scores showed no correlation to one another. Interestingly, the sole correlation between methods seen is between illuminance and NIBUT for patients with illuminance <3000 lux and the time in both eyes <5 seconds, with a linear r2 correlation of 0.91.
We observed strong evidence of a measurable relation between preferred illuminance and DED symptoms. Of the four diagnostic methods used in this study, preferred illuminance was the most consistent, a promising result as it is also the quickest, simplest, and least invasive of the methods. The correlation between short NIBUT times and preferred illuminance further supports the conclusion that preferred illuminance is a valid indicator of DED. We are continuing this IRB-approved study, and expect to evaluate significantly more patients.