Flexible ultrasound-induced retinal stimulating piezo-arrays for biomimetic visual prostheses

Abstract

Electronic visual prostheses, or biomimetic eyes, have shown the feasibility of restoring functional vision in the blind through electrical pulses to initiate neural responses artificially. However, existing visual prostheses predominantly use wired connections or electromagnetic waves for powering and data telemetry, which raises safety concerns or couples inefficiently to miniaturized implant units. Here, we present a flexible ultrasound-induced retinal stimulating piezo-array that can offer an alternative wireless artificial retinal prosthesis approach for evoking visual percepts in blind individuals. The device integrates a two-dimensional piezo-array with 32-pixel stimulating electrodes in a flexible printed circuit board. Each piezo-element can be ultrasonically and individually activated, thus, spatially reconfigurable electronic patterns can be dynamically applied via programmable ultrasound beamlines. As a proof of concept, we demonstrate the ultrasound-induced pattern reconstruction in ex vivo murine retinal tissue, showing the potential of this approach to restore functional, life-enhancing vision in people living with blindness.

Recent progress in flexible piezoelectric devices toward human-machine interactions

“…Piezoelectric devices play an extraordinary role in the field of acoustic therapeutics due to their efficient bidirectional electromechanical coupling capability. For example, Zhang et al reported a piezoelectric ultrasound energyharvesting (PUEH) device that could be implanted underneath the skin for deep brain stimulation by converting ultrasound energy to electrical energy [Figure 5A] [82] . As schematically illustrated in Figure 5B, the designed harvester was a multilayer structured device with a Sm-doped Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (Sm-PMN-PT) single crystal as the functional layer.…”

“…Each piezo-element could be respectively activated by ultrasound, which was individually transduced by Reproduced with permission from ref. [82] . Copyright 2022, American Association for the Advancement of Science.…”

“…(A) Schematic diagram of Sm-PUEH device for deep brain stimulation and analgesia. (B) Structural diagram of Sm-PUEH.Reproduced with permission from ref [82]. .…”

Ultrasound stimulation for non-invasive visual prostheses

“…Typically, ultrasound transducers consume high power; therefore, future ultrasound-based visual prostheses must enable low-power neuromodulation not only for the light-weight batteries but also for less heat generation. Several recent attempts have provided some solutions for the power issue with the wireless energy transfer such as ultrasonic power delivery ( Jiang et al, 2022 ).…”

Wearable respiratory sensors for COVID‐19 monitoring

“… 24 Thus, direct measurement of respiratory biomarkers, for example, respiratory rate, cough frequency, cough intensity, respiratory effort, and on‐site viral‐specific VOCs, 25 represent a potential game‐changer in the diagnosis, monitoring, and management of COVID‐19. 26 To date, bioelectronics, the convergence of biological systems and electronic devices, have witnessed tremendous progress in wide applications, 27 , 28 , 29 , 30 , 31 , 32 , 33 such as biosensing, 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 electrical stimulations, 45 , 46 , 47 neuromodulation, 48 drug delivery, 49 , 50 , 51 energy harvesting, 52 , 53 , 54 energy storage, 55 , 56 , 57 thermoregulation, 58 display, 55 imaging, 59 and many others. Specifically, respiratory sensors propelled by advanced bioelectronic technology have been widely used for health assessment, disease diagnosis, and treatment tracking in daily life.…”