Ultrasound elastography using regularized phase-zero cost function initialized with dynamic programming

Shahin Sefati, Hassan Rivaz, Emad Boctor, Gregory Hager

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

Abstract

Elastography, computation of elasticity modulus of tissue is one of medical imaging methods with applications such as tumor detection and ablation therapy. Phase-based time delay estimation methods exploit the frequency information of the RF data to obtain strain estimates [1]. Although iterative Phase zero estimation is more computationally efficient in comparison to methods that seek for the absolute maximum cross-correlation between precompression and postcompression echo signals, it is quite sensitive to noise. The reason for this sensitivity is that for this iterative method an initial guess for the time shift is needed for each pixel. To estimate time shifts for the sample k, the time shift resulted from iterative phase zero method applied on sample k-1 is used as an initial value. This makes the method sensitive to noise because the error is propagating sample by sample and if the method gets unstable for any pixel, it will give unstable result for the following pixels in image line. Proposed strategy in this work to overcome this problem is to first estimate the displacement using Dynamic Programming [2] and use the results from DP as an initial guess of displacement for each pixel in iterative Phase zero method. Recently, regularized methods that incorporate the prior of tissue continuity in time delay estimation have been shown to produce low-noise and high contrast strain images [3,5]. In this work, we also incorporate the prior of tissue motion continuity in the phase zero method to make the zero-phase method more robust to signal decorrelation.

Original languageEnglish (US)
Title of host publicationProgress in Biomedical Optics and Imaging - Proceedings of SPIE
Volume7968
DOIs
StatePublished - 2011
EventMedical Imaging 2011: Ultrasonic Imaging, Tomography, and Therapy - Lake Buena Vista, FL, United States
Duration: Feb 13 2011Feb 14 2011

Other

OtherMedical Imaging 2011: Ultrasonic Imaging, Tomography, and Therapy
CountryUnited States
CityLake Buena Vista, FL
Period2/13/112/14/11

Fingerprint

Elasticity Imaging Techniques
dynamic programming
Dynamic programming
Cost functions
Ultrasonics
Pixels
pixels
costs
Costs and Cost Analysis
Tissue
continuity
shift
Time delay
modulus of elasticity
time lag
estimates
Medical imaging
Ablation
Iterative methods
Noise

Keywords

  • Dynamic Programming
  • Phase Phase-zero
  • Ultrasound Elastography

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Radiology Nuclear Medicine and imaging

Cite this

Sefati, S., Rivaz, H., Boctor, E., & Hager, G. (2011). Ultrasound elastography using regularized phase-zero cost function initialized with dynamic programming. In Progress in Biomedical Optics and Imaging - Proceedings of SPIE (Vol. 7968). [79681D] https://doi.org/10.1117/12.878247

Ultrasound elastography using regularized phase-zero cost function initialized with dynamic programming. / Sefati, Shahin; Rivaz, Hassan; Boctor, Emad; Hager, Gregory.

Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7968 2011. 79681D.

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

Sefati, S, Rivaz, H, Boctor, E & Hager, G 2011, Ultrasound elastography using regularized phase-zero cost function initialized with dynamic programming. in Progress in Biomedical Optics and Imaging - Proceedings of SPIE. vol. 7968, 79681D, Medical Imaging 2011: Ultrasonic Imaging, Tomography, and Therapy, Lake Buena Vista, FL, United States, 2/13/11. https://doi.org/10.1117/12.878247
Sefati S, Rivaz H, Boctor E, Hager G. Ultrasound elastography using regularized phase-zero cost function initialized with dynamic programming. In Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7968. 2011. 79681D https://doi.org/10.1117/12.878247
Sefati, Shahin ; Rivaz, Hassan ; Boctor, Emad ; Hager, Gregory. / Ultrasound elastography using regularized phase-zero cost function initialized with dynamic programming. Progress in Biomedical Optics and Imaging - Proceedings of SPIE. Vol. 7968 2011.
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