title: Continuous in vivo blood pressure measurements using a fully implantable wireless SAW sensor.
abstract: In this paper, the development of a fully implantable wireless sensor able to provide continuous real-time accurate pressure measurements is presented. Surface Acoustic Wave (SAW) technology was used to deposit resonators on crystalline quartz wafers; the wafers were then assembled to produce a pressure sensitive device. Excitation and reading via a miniature antenna attached to the pressure sensor enables continuous external interrogation. The main advantages of such a configuration are the long term stability of quartz and the low power necessary for the interrogation, which allows 24/7 interrogation by means of a hand-held, battery powered device. Such data are of vital importance to clinicians monitoring and treating the effects of hypertension and heart failure. A prototype was designed and tested using both a bio-phantom test rig and an animal model. The pressure traces for both compare very well with a commercially available catheter tip pressure transducer. The work presented in this paper is the first known wireless pressure data from the left ventricle of the heart of a living swine.
authors.affiliation: Centre for Bio-Inspired Technology, Institute of Biomedical Engineering and the Department of Electrical and Electronic Engineering, Imperial College London, London, SW7 2AZ, UK. o.murphy@imperial.ac.uk
authors.forename: Olive H
authors.initials: OH
authors.lastname: Murphy
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Bahmanyar
authors.forename: Alessandro
authors.initials: A
authors.lastname: Borghi
authors.forename: Christopher N
authors.initials: CN
authors.lastname: McLeod
authors.forename: Manoraj
authors.initials: M
authors.lastname: Navaratnarajah
authors.forename: Magdi H
authors.initials: MH
authors.lastname: Yacoub
authors.forename: Christofer
authors.initials: C
authors.lastname: Toumazou
mesh_terms: D000818:Animals; D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D023421:Models, Animal; D019736:Prostheses and Implants; D013552:Swine; D014160:Transducers, Pressure; D059015:Wireless Technology
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