Virtual prototyping of a catheter transducer array for internal hepatic sonoporation

Alexandru Corneliu Moldovan, Jerzy Dziewierz, Anthony Gachagan, Sandy Cochran, Holly Lay

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

Abstract

Sonoporation for targeted cancer chemotherapy in the liver with an external ultrasonic source is hampered by the ribs and fat surrounding the organ. Current therapies rely on array beam forming with sequential triggering of elements to spare the ribs. However, the peak negative pressures (PNPs) achieved in hepatic tumors are rather low and there is risk associated with high power ultrasound incident on the ribs. Here, we focus on the development of a 1-3 connectivity piezocomposite linear ultrasonic array that can be incorporated in an 11 Fr catheter to perform sonoporation of the liver from within a larger blood vessel. Issues encountered in the transducer design are mostly caused by the reduced dimensions of the catheter, which are inimical to the low frequency and high power therapeutic requirements. Thus, our approach to produce a transducer design is through a series of parametric sweeps of array parameters using finite element analysis. The output parameters of interest are PNP and beam forming to steer at more than 45° from normal. Two frequencies are considered: 1.5 MHz, set by the maximum physical transducer thickness, and 3.0 MHz, corresponding to the frequency of resonance of the contrast agents to carry the drugs. Piezoelectric materials of interest are ceramic (PZT-5H) and single crystal (PMN-29%PT, 26%PIN-PMN-32%PT). The parametric sweeps indicate that fewer pillars laterally per element, higher volume fraction (>0.68) and higher pillar aspect ratio (>0.42) achieve the lowest PNP in the load.
LanguageEnglish
Title of host publication2018 IEEE International Ultrasonics Symposium (IUS)
Place of PublicationPiscataway, NJ
PublisherIEEE
Number of pages4
ISBN (Electronic)9781538634257
DOIs
Publication statusPublished - 20 Dec 2018
Event2018 IEEE International Ultrasonics Symposium - Portopia Hotel, Kobe, Japan
Duration: 22 Oct 201825 Oct 2018

Conference

Conference2018 IEEE International Ultrasonics Symposium
Abbreviated titleIUS 2018
CountryJapan
CityKobe
Period22/10/1825/10/18

Fingerprint

Catheters
Transducers
Ultrasonics
Liver
Chemotherapy
Piezoelectric materials
Blood vessels
Oils and fats
Aspect ratio
Tumors
Volume fraction
Single crystals
Finite element method
Virtual prototyping

Keywords

  • phased array transducer
  • finite element modelling
  • beamforming

Cite this

Moldovan, A. C., Dziewierz, J., Gachagan, A., Cochran, S., & Lay, H. (2018). Virtual prototyping of a catheter transducer array for internal hepatic sonoporation. In 2018 IEEE International Ultrasonics Symposium (IUS) Piscataway, NJ: IEEE. https://doi.org/10.1109/ULTSYM.2018.8579783
Moldovan, Alexandru Corneliu ; Dziewierz, Jerzy ; Gachagan, Anthony ; Cochran, Sandy ; Lay, Holly. / Virtual prototyping of a catheter transducer array for internal hepatic sonoporation. 2018 IEEE International Ultrasonics Symposium (IUS). Piscataway, NJ : IEEE, 2018.
@inproceedings{b995e08f42d845389798289dda32bb7d,
title = "Virtual prototyping of a catheter transducer array for internal hepatic sonoporation",
abstract = "Sonoporation for targeted cancer chemotherapy in the liver with an external ultrasonic source is hampered by the ribs and fat surrounding the organ. Current therapies rely on array beam forming with sequential triggering of elements to spare the ribs. However, the peak negative pressures (PNPs) achieved in hepatic tumors are rather low and there is risk associated with high power ultrasound incident on the ribs. Here, we focus on the development of a 1-3 connectivity piezocomposite linear ultrasonic array that can be incorporated in an 11 Fr catheter to perform sonoporation of the liver from within a larger blood vessel. Issues encountered in the transducer design are mostly caused by the reduced dimensions of the catheter, which are inimical to the low frequency and high power therapeutic requirements. Thus, our approach to produce a transducer design is through a series of parametric sweeps of array parameters using finite element analysis. The output parameters of interest are PNP and beam forming to steer at more than 45° from normal. Two frequencies are considered: 1.5 MHz, set by the maximum physical transducer thickness, and 3.0 MHz, corresponding to the frequency of resonance of the contrast agents to carry the drugs. Piezoelectric materials of interest are ceramic (PZT-5H) and single crystal (PMN-29{\%}PT, 26{\%}PIN-PMN-32{\%}PT). The parametric sweeps indicate that fewer pillars laterally per element, higher volume fraction (>0.68) and higher pillar aspect ratio (>0.42) achieve the lowest PNP in the load.",
keywords = "phased array transducer, finite element modelling, beamforming",
author = "Moldovan, {Alexandru Corneliu} and Jerzy Dziewierz and Anthony Gachagan and Sandy Cochran and Holly Lay",
note = "{\circledC} 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.",
year = "2018",
month = "12",
day = "20",
doi = "10.1109/ULTSYM.2018.8579783",
language = "English",
booktitle = "2018 IEEE International Ultrasonics Symposium (IUS)",
publisher = "IEEE",

}

Moldovan, AC, Dziewierz, J, Gachagan, A, Cochran, S & Lay, H 2018, Virtual prototyping of a catheter transducer array for internal hepatic sonoporation. in 2018 IEEE International Ultrasonics Symposium (IUS). IEEE, Piscataway, NJ, 2018 IEEE International Ultrasonics Symposium, Kobe, Japan, 22/10/18. https://doi.org/10.1109/ULTSYM.2018.8579783

Virtual prototyping of a catheter transducer array for internal hepatic sonoporation. / Moldovan, Alexandru Corneliu; Dziewierz, Jerzy; Gachagan, Anthony; Cochran, Sandy; Lay, Holly.

2018 IEEE International Ultrasonics Symposium (IUS). Piscataway, NJ : IEEE, 2018.

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

TY - GEN

T1 - Virtual prototyping of a catheter transducer array for internal hepatic sonoporation

AU - Moldovan, Alexandru Corneliu

AU - Dziewierz, Jerzy

AU - Gachagan, Anthony

AU - Cochran, Sandy

AU - Lay, Holly

N1 - © 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.

PY - 2018/12/20

Y1 - 2018/12/20

N2 - Sonoporation for targeted cancer chemotherapy in the liver with an external ultrasonic source is hampered by the ribs and fat surrounding the organ. Current therapies rely on array beam forming with sequential triggering of elements to spare the ribs. However, the peak negative pressures (PNPs) achieved in hepatic tumors are rather low and there is risk associated with high power ultrasound incident on the ribs. Here, we focus on the development of a 1-3 connectivity piezocomposite linear ultrasonic array that can be incorporated in an 11 Fr catheter to perform sonoporation of the liver from within a larger blood vessel. Issues encountered in the transducer design are mostly caused by the reduced dimensions of the catheter, which are inimical to the low frequency and high power therapeutic requirements. Thus, our approach to produce a transducer design is through a series of parametric sweeps of array parameters using finite element analysis. The output parameters of interest are PNP and beam forming to steer at more than 45° from normal. Two frequencies are considered: 1.5 MHz, set by the maximum physical transducer thickness, and 3.0 MHz, corresponding to the frequency of resonance of the contrast agents to carry the drugs. Piezoelectric materials of interest are ceramic (PZT-5H) and single crystal (PMN-29%PT, 26%PIN-PMN-32%PT). The parametric sweeps indicate that fewer pillars laterally per element, higher volume fraction (>0.68) and higher pillar aspect ratio (>0.42) achieve the lowest PNP in the load.

AB - Sonoporation for targeted cancer chemotherapy in the liver with an external ultrasonic source is hampered by the ribs and fat surrounding the organ. Current therapies rely on array beam forming with sequential triggering of elements to spare the ribs. However, the peak negative pressures (PNPs) achieved in hepatic tumors are rather low and there is risk associated with high power ultrasound incident on the ribs. Here, we focus on the development of a 1-3 connectivity piezocomposite linear ultrasonic array that can be incorporated in an 11 Fr catheter to perform sonoporation of the liver from within a larger blood vessel. Issues encountered in the transducer design are mostly caused by the reduced dimensions of the catheter, which are inimical to the low frequency and high power therapeutic requirements. Thus, our approach to produce a transducer design is through a series of parametric sweeps of array parameters using finite element analysis. The output parameters of interest are PNP and beam forming to steer at more than 45° from normal. Two frequencies are considered: 1.5 MHz, set by the maximum physical transducer thickness, and 3.0 MHz, corresponding to the frequency of resonance of the contrast agents to carry the drugs. Piezoelectric materials of interest are ceramic (PZT-5H) and single crystal (PMN-29%PT, 26%PIN-PMN-32%PT). The parametric sweeps indicate that fewer pillars laterally per element, higher volume fraction (>0.68) and higher pillar aspect ratio (>0.42) achieve the lowest PNP in the load.

KW - phased array transducer

KW - finite element modelling

KW - beamforming

UR - http://sites.ieee.org/ius-2018/

U2 - 10.1109/ULTSYM.2018.8579783

DO - 10.1109/ULTSYM.2018.8579783

M3 - Conference contribution book

BT - 2018 IEEE International Ultrasonics Symposium (IUS)

PB - IEEE

CY - Piscataway, NJ

ER -

Moldovan AC, Dziewierz J, Gachagan A, Cochran S, Lay H. Virtual prototyping of a catheter transducer array for internal hepatic sonoporation. In 2018 IEEE International Ultrasonics Symposium (IUS). Piscataway, NJ: IEEE. 2018 https://doi.org/10.1109/ULTSYM.2018.8579783