Contact lenses for continuous corneal temperature monitoring
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Published version
Author(s)
Moreddu, Rosalia
Elsherif, Mohamed
Butt, Haider
Vigolo, Daniele
Yetisen, Ali Kemal
Type
Journal Article
Abstract
Temperature variation is a ubiquitous medical sign to monitor ocular conditions including dry eye disease (DED), glaucoma, carotid artery stenosis, diabetic retinopathy, and vascular neuritis. The ability to measure OST in real time is desirable in point-of-care diagnostics. Here, we developed minimally invasive contact lens temperature sensors for continuous monitoring of the corneal temperature. The contact lens sensor consisted of a laser patterned commercial contact lens embedding temperature-sensitive Cholesteric Liquid Crystals (CLCs), which exhibited a fully reversible temperature-dependent color change in the visible spectrum. The contact lens allowed the corneal temperature to be mapped in four key areas, at distances of 0.0, 1.0, 3.0, and 5.0 mm from the pupil's edge. Liquid crystals exhibited a wavelength shift from 738 ± 4 nm to 474 ± 4 nm upon increasing the temperature from 29.0 °C to 40.0 °C, with a time responsivity of 490 ms and a negligible hysteresis. Readouts were performed using a smartphone, which output RGB triplets associated to temperature values. Contact lens sensors based on CLCs were fitted and tested on an ex vivo porcine eye and readouts were compared with infrared thermal measurements, resulting in an average difference of 0.3 °C.
Date Issued
2019-04-11
Date Acceptance
2019-04-05
Citation
RSC Advances, 2019, 9 (20), pp.11433-11442
ISSN
2046-2069
Publisher
Royal Society of Chemistry
Start Page
11433
End Page
11442
Journal / Book Title
RSC Advances
Volume
9
Issue
20
Copyright Statement
© The Royal Society of Chemistry 2019. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence (https://creativecommons.org/licenses/by-nc/3.0/)
Publication Status
Published
Date Publish Online
2019-04-11