Optimization of transcostal phased-array refocusing using sparse semidefinite relaxation method

Mohamed Almekkawy, Daniel McMahon, Hanan Alqarni, Jiayu He

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

7 Scopus citations

Abstract

Treating tumors in organs shadowed by the ribs is a challenge for high intensity focused ultrasound (HIFU). The ribs absorb energy from the ultrasound beams causing their temperature to rise, while also distorting the beams, and limiting the target heat deposition. Accordingly, it is necessary to devise focusing methods that address the difficulties presented by the ribs. In this paper, a new approach that reduces total power deposition on the region of interest (ROI) by removing transducer elements is introduced. The method builds on the limited power deposition (LPD) method, which took advantage of the semidefinite relaxation (SDR) method to relax nonconvex constraints into convex form. The method introduced in this paper induces sparsity using the one-norm squared. The results of using this method to focus a 1-MHz spherical phased array on a target in an inhomogeneous medium are presented and compared to the ray tracing (shadowing) approach [1]. A finite-difference time domain propagation model was used to model the wave propagation to the target. Temperature simulations that utilized the inhomogeneous bioheat transfer equation (BHTE) illustrate the advantages of the induced sparsity LPD method. Together, these simulation results illustrate the advantages of using optimization based on sparsity inducing techniques over the shadowing approach.

Original languageEnglish (US)
Title of host publication2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Subtitle of host publicationSmarter Technology for a Healthier World, EMBC 2017 - Proceedings
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages1449-1452
Number of pages4
ISBN (Electronic)9781509028092
DOIs
StatePublished - Sep 13 2017
Event39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC 2017 - Jeju Island, Korea, Republic of
Duration: Jul 11 2017Jul 15 2017

Publication series

NameProceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS
ISSN (Print)1557-170X

Other

Other39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC 2017
Country/TerritoryKorea, Republic of
CityJeju Island
Period7/11/177/15/17

All Science Journal Classification (ASJC) codes

  • Signal Processing
  • Biomedical Engineering
  • Computer Vision and Pattern Recognition
  • Health Informatics

Fingerprint

Dive into the research topics of 'Optimization of transcostal phased-array refocusing using sparse semidefinite relaxation method'. Together they form a unique fingerprint.

Cite this