The integration of bulk PZT transducers in a microfabricated cuff implant for Vagus Nerve ultrasound neuromodulation

The integration of bulk PZT transducers in a microfabricated cuff implant for Vagus Nerve ultrasound neuromodulation: Simulation, design and fabrication

van Damme, Niels (TU Delft Electrical Engineering, Mathematics and Computer Science)

Velea, A. (graduation committee)
Wardhana, Gandhika K (graduation committee)
Mastrangeli, Massimo (graduation committee)
Lopes Marta da Costa, T.M. (mentor)
Giagka, Vasiliki (mentor)

Delft University of Technology

Electrical Engineering

2023-09-25

In the emerging research field of bioelectronic medicine, it has been indicated that neuromodulation of the Vagus Nerve (VN) has the potential to treat various conditions such as epilepsy, depression, and autoimmune diseases. In order to reduce side effects, as well as to increase the effectiveness of the delivered therapy, sub-fascicle stimulation specificity is required. In the electrical domain, increasing spatial selectivity can only be achieved using invasive and potentially damaging approaches like compressive forces or nerve penetration. To avoid these invasive methods, while obtaining a high spatial selectivity, a 2 mm diameter extraneural cuff-shaped proof-of-concept design with integrated Lead Zirconate Titanate (PZT) piezoelectric ultrasound transducers is proposed. For the development of the proposed concept, wafer-level microfabrication techniques are employed. Moreover, acoustic measurements are performed on the device, in order to characterize the ultrasonic beam profiles of the integrated PZT-based piezoelectric ultrasound transducers. A focal spot size of 200 μm by 200 μm is measured for the proposed cuff. Moreover, the curvature of the device leads to constructive interference of the ultrasound waves originating from multiple piezoelectric ultrasound transducers, which in turn leads to an increase of 45% in focal pressure compared to the focal pressure of a single piezoelectric ultrasound transducer. Integrating piezoelectric ultrasound transducers in an extraneural cuff-shaped design has the potential to achieve high-precision ultrasound neuromodulation of the Vagus Nerve without requiring intraneural implantation.

Cuff implant
Flex-to-Rigid
Microfabrication
piezoelectric ultrasound transducers
PZT integration
ultrasound neuromodulation
vagus nerve neuromodulation

http://resolver.tudelft.nl/uuid:ffff622e-4394-4c41-9568-d3199c9b7956

2025-09-30

Student theses

master thesis

© 2023 Niels van Damme