Highly sensitive wireless dual-spiral resonant contact lens for continuous intraocular pressure monitoring.

Abstract

Continuous and non-invasive intraocular pressure (IOP) monitoring is crucial for managing glaucoma, a leading cause of irreversible blindness worldwide. However, existing tonometry methods are intermittent and lack the capability to capture dynamic IOP fluctuations. Herein, we present a highly sensitive, wireless contact lens (WCL) sensor based on a dual-spiral inductor-capacitor-resistor (LCR) resonator for real-time IOP monitoring. The sensor features an axisymmetric anti-parallel spiral architecture that synergistically enhances capacitive coupling and suppresses inductive mutual coupling, thereby amplifying the resonant frequency shift in response to corneal biomechanical deformation. Furthermore, a gradient line-width strategy is implemented to minimize resistive loss, concentrate charge density, and improve mechanical robustness. Systematic evaluations on a biomimetic eyeball platform and <i>ex vivo</i> porcine eyes demonstrate high sensitivity, with values of -1.839 MHz mmHg^-1 and -0.69 MHz mmHg^-1, respectively. These results highlight the potential of the WCL as a robust and scalable platform for continuous, non-invasive IOP monitoring in glaucoma management.