Ultrasound‐Powered Implants: A Critical Review of Piezoelectric Material Selection and Applications. Issue 17 (8th July 2021)

• Record Type: Journal Article
• Authors: Turner, Brendan L.; Senevirathne, Seedevi; Kilgour, Katie; McArt, Darragh; Biggs, Manus; Menegatti, Stefano; Daniele, Michael A.
• Other Names: Gao Wei guestEditor.; Yu Cunjiang guestEditor.
• Is Part Of: Advanced healthcare materials. Volume 10:Issue 17(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-07-08
• Subjects: energy harvesting -- implantable medical devices -- piezoelectric devices -- ultrasound -- wireless power transfer; Biomedical materials -- Periodicals; 610.28
• DOI: 10.1002/adhm.202100986
• Languages: English
• ISSNs: 2192-2640

Abstract

Abstract: Ultrasound‐powered implants (UPIs) represent cutting edge power sources for implantable medical devices (IMDs), as their powering strategy allows for extended functional lifetime, decreased size, increased implant depth, and improved biocompatibility. IMDs are limited by their reliance on batteries. While batteries proved a stable power supply, batteries feature relatively large sizes, limited life spans, and toxic material compositions. Accordingly, energy harvesting and wireless power transfer (WPT) strategies are attracting increasing attention by researchers as alternative reliable power sources. Piezoelectric energy scavenging has shown promise for low power applications. However, energy scavenging devices need be located near sources of movement, and the power stream may suffer from occasional interruptions. WPT overcomes such challenges by more stable, on‐demand power to IMDs. Among the various forms of WPT, ultrasound powering offers distinct advantages such as low tissue‐mediated attenuation, a higher approved safe dose (720 mW cm −2 ), and improved efficiency at smaller device sizes. This study presents and discusses the state‐of‐the‐art in UPIs by reviewing piezoelectric materials and harvesting devices including lead‐based inorganic, lead‐free inorganic, and organic polymers. A comparative discussion is also presented of the functional material properties, architecture, and performance metrics, together with an overview of the applications where UPIs are being deployed. Abstract : State‐of‐the‐art review for externally powered implantable medical devices focusing on the piezoelectric materials and systemsnecessary to deploy ultrasound‐powered implants (UPIs). Components in UPIs are evaluated including piezoelectric receiver design. A review of energy harvesting potential for lead‐based ceramics, lead‐free ceramics, and organic polymers is presented. Finally, reported UPIs are compared with devices currently on‐the‐market and alternatives reported in literature.