Continuous detection of raised intraocular pressure (IOP) could benefit the monitoring of patients with glaucoma. Current contact lenses with embedded sensors for measuring IOP are rigid, bulky, partially block vision or are insufficiently sensitive. Here, we report the design and testing in volunteers of a soft and transparent contact lens for the quantitative monitoring of IOP in real time using a smartphone. The contact lens incorporates a strain sensor, a wireless antenna, capacitors, resistors, stretchable metal interconnects and an integrated circuit for wireless communication. In rabbits, the lens provided measurements that match those of a commercial tonometer. In ten human participants, the lens proved to be safe, and reliably provided accurate quantitative measurements of IOP without inducing inflammation.
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The rabbit in vivo data are available at Figshare (https://doi.org/10.6084/m9.figshare.13289342)52. The human data are available within the paper and its Supplementary Information. The raw and analysed datasets generated for the studies shown in Figs. 1–3 are available for research purposes from the corresponding authors on reasonable request.
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This work was supported by the Ministry of Science & ICT (MSIT) and the Ministry of Trade, Industry and Energy (MOTIE) of Korea through the National Research Foundation (2019R1A2B5B03069358 and 2016R1A5A1009926), the Bio & Medical Technology Development Program (2018M3A9F1021649), the Nano Material Technology Development Program (2016M3A7B4910635) and the Technology Innovation Program (20010366 and 20013621, Center for Super Critical Material Industrial Technology). We also acknowledge financial support from the Institute for Basic Science (IBS-R026-D1), the Research Program (2019-22-0228) and the Post Doc Researcher Supporting program of 2019 (2019-12-0010) funded by Yonsei University.
The authors declare no competing interests.
Peer review information Nature Biomedical Engineering thanks the anonymous reviewers for their contribution to the peer review of this work.
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Supplementary Methods, Figs. 1–30 and Table 1, and captions for Supplementary Videos 1–3.
IOP data for the ten human volunteers.
In vivo trial of the soft contact lens for recording IOP.
In vivo test conducted using a live rabbit for monitoring the generation of heat during the wireless operation of the contact lens.
Human pilot trial of the soft contact lens.
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Kim, J., Park, J., Park, YG. et al. A soft and transparent contact lens for the wireless quantitative monitoring of intraocular pressure. Nat Biomed Eng 5, 772–782 (2021). https://doi.org/10.1038/s41551-021-00719-8