title: Double Ring Array Catheter for In Vivo Real-Time 3D Ultrasound.
abstract: We developed new forward-viewing matrix transducers consisting of double ring arrays of 118 total PZT elements integrated into catheters used to deploy medical interventional devices. Our goal is 3D ultrasound guidance of medical device implantation to reduce x-ray fluoroscopy exposure. The double ring arrays were fabricated on inner and outer custom polyimide flexible circuits with inter-element spacing of 0.20 mm and then wrapped around an 11 French (Fr) catheter to produce a 15 Fr catheter (outer diameter [O.D.]). We used a braided cabling technology to connect the elements to the Volumetrics Medical Imaging (VMI) real-time 3D ultrasound scanner. Transducer performance yielded an average -6 dB fractional bandwidth of 49% ± 11% centered at 4.4 MHz for 118 elements. Real-time 3D cardiac scans of the in vivo pig model yielded good image quality including en face views of the tricuspid valve and real-time 3D guidance of an endo-myocardial biopsy catheter introduced into the left ventricle.
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, NC, USA ssmith@duke.edu.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Smith
authors.affiliation: Covarx Corporation, Apex, NC, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Gardea
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, NC, USA.
authors.forename: Vivek
authors.initials: V
authors.lastname: Patel
authors.affiliation: Covarx Corporation, Apex, NC, USA.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Douglas
authors.affiliation: Department of Biomedical Engineering, Duke University, Durham, NC, USA.
authors.forename: Patrick D
authors.initials: PD
authors.lastname: Wolf
keywords: 2D array transducer; cardiac; catheter; interventional devices; real-time 3D imaging