Correlation-based ultrasound imaging of strong reflectors with phase coherence filtering

• Published in: Ultrasonics Vol. 119; p. 106631
• Main Authors: Bilodeau, M., Quaegebeur, N., Berry, A., Masson, P.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.02.2022
• Subjects: Algorithms; Correlation-based imaging; Excitelet; Image Enhancement - methods; Image Processing, Computer-Assisted - methods; Phase Coherence; Surgical Instruments; Transducers; Ultrasonic imaging; Ultrasonography - methods; Correlation-based imaging; Ultrasonic imaging; Phase Coherence; Excitelet
• ISSN: 0041-624X; 1874-9968
• DOI: 10.1016/j.ultras.2021.106631

Two main metrics are usually employed to assess the quality of medical ultrasound (US) images, namely the contrast and the spatial resolution. A number of imaging algorithms have been proposed to improve one of those metrics, often at the expense of the other one. This paper presents the application of a correlation-based ultrasound imaging method, called Excitelet, to medical US imaging applications and the inclusion of a new Phase Coherence (PC) metric within its formalism. The main idea behind this algorithm, originally developed and validated for Non-Destructive Testing (NDT) applications, is to correlate a reference signal database with the measured signals acquired from a transducer array. In this paper, it is shown that improved lateral resolutions and a reduction of imaging artifacts are obtained over the Synthetic Aperture Focusing Technique (SAFT) when using Excitelet in conjunction with a PC filter. This novel method shows potential for the imaging of specular reflectors, such as invasive surgical tools. Numerical and experimental results presented in this paper demonstrate the benefit, in terms of contrast and resolution, of using the Excitelet method combined with PC for the imaging of strong reflectors. •A new phase coherence filter is presented for improved contrasts.•The correlation-based algorithm Excitelet is applied to ultrasound medical imaging.•Excitelet outperforms the synthetic aperture method in terms of resolutions.•The correlation-based method is efficient for the imaging of surgical tools.