A Novel Racing Array Transducer for Noninvasive Ultrasonic Retinal Stimulation: A Simulation Study

Area of Science:

• Biomedical Engineering
• Ophthalmology
• Acoustic Technology

Background:

• Neurostimulation restores vision in retinal diseases but current methods use invasive electrodes, posing risks and high costs.
• Noninvasive neurostimulation is desirable, with ultrasound emerging as a promising approach.

Purpose of the Study:

• To propose and evaluate a novel, noninvasive contact lens-shaped ultrasound transducer for retinal stimulation.
• To optimize the transducer design for effective and high-resolution retinal stimulation.

Main Methods:

• A flexible, contact lens-shaped racing array transducer was designed for external eye placement.
• The discretized Rayleigh-Sommerfeld method was used for acoustic field simulation and patterned stimulation analysis.
• Simulations were performed on a 5 MHz transducer with varying element numbers to determine optimal configuration.

Main Results:

• A 512-element racing array transducer configuration was identified as optimal, balancing element count and stimulation resolution.
• The proposed transducer design minimizes acoustic absorption by bypassing the eye lens.
• A stimulation resolution of approximately 0.6 mm was achieved at a focal depth of 24 mm.

Conclusions:

• The novel racing array ultrasound transducer design enhances the feasibility of noninvasive ultrasound retinal prostheses.
• This technology offers a potential high-resolution, lower-risk alternative for vision restoration in patients with retinal diseases.