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Ultrasonic transducer-guided electrochemical impedance spectroscopy to assess lipid-laden plaques

Ma, Jianguo and Luo, Yuan and Packard, René R. Sevag and Ma, Teng and Ding, Yichen and Abiri, Parinaz and Tai, Yu-Chong and Zhou, Qifa and Shung, Kirk K. and Li, Rongsong and Hsiai, Tzung (2016) Ultrasonic transducer-guided electrochemical impedance spectroscopy to assess lipid-laden plaques. Sensors and Actuators B: Chemical, 235 . pp. 154-161. ISSN 0925-4005. PMCID PMC5068578.

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Plaque rupture causes acute coronary syndromes and stroke. Intraplaque oxidized low density lipoprotein (oxLDL) is metabolically unstable and prone to induce rupture. We designed an intravascular ultrasound (IVUS)-guided electrochemical impedance spectroscopy (EIS) sensor to enhance the detection reproducibility of oxLDL-laden plaques. The flexible 2-point micro-electrode array for EIS was affixed to an inflatable balloon anchored onto a co-axial double layer catheter (outer diameter = 2 mm). The mechanically scanning-driven IVUS transducer (45 MHz) was deployed through the inner catheter (diameter = 1.3 mm) to the acoustic impedance matched-imaging window. Water filled the inner catheter to match acoustic impedance and air was pumped between the inner and outer catheters to inflate the balloon. The integrated EIS and IVUS sensor was deployed into the ex vivo aortas dissected from the fat-fed New Zealand White (NZW) rabbits (n = 3 for fat-fed, n = 5 normal diet). IVUS imaging was able to guide the 2-point electrode to align with the plaque for EIS measurement upon balloon inflation. IVUS-guided EIS signal demonstrated reduced variability and increased reproducibility (p < 0.0001 for magnitude, p < 0.05 for phase at <15 kHz) as compared to EIS sensor alone (p < 0.07 for impedance, p < 0.4 for phase at <15 kHz). Thus, we enhanced topographic and EIS detection of oxLDL-laden plaques via a catheter-based integrated sensor design to enhance clinical assessment for unstable plaque.

Item Type:Article
Related URLs:
URLURL TypeDescription CentralArticle
Packard, René R. Sevag0000-0002-8520-5843
Ding, Yichen0000-0002-6242-3506
Tai, Yu-Chong0000-0001-8529-106X
Hsiai, Tzung0000-0003-1734-0792
Additional Information:© 2016 Elsevier B.V. Received 11 February 2016, Revised 26 April 2016, Accepted 27 April 2016, Available online 7 May 2016. The Authors acknowledge the support by the National Institute of Heath grants R01HL083015 (TKH), R01HL118650 (TKH), R01HL129727 (TKH), R01HL111437 (TKH), P41-EB02182 (QZ, KKS).
Funding AgencyGrant Number
Subject Keywords:Ultrasonic transducers; Flexible 2-point electrode; Electrochemical impedance spectroscopy; Dual sensor-based intravascular catheter; Plaque assessment
PubMed Central ID:PMC5068578
Record Number:CaltechAUTHORS:20160915-082808353
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Official Citation:Jianguo Ma, Yuan Luo, René R.Sevag Packard, Teng Ma, Yichen Ding, Parinaz Abiri, Yu-Chong Tai, Qifa Zhou, Kirk K. Shung, Rongsong Li, Tzung Hsiai, Ultrasonic transducer-guided electrochemical impedance spectroscopy to assess lipid-laden plaques, Sensors and Actuators B: Chemical, Volume 235, 1 November 2016, Pages 154-161, ISSN 0925-4005, (
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:70359
Deposited By: Tony Diaz
Deposited On:28 Sep 2016 17:13
Last Modified:26 Nov 2019 17:50

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