Cystic resolution: A performance metric for ultrasound imaging systems

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 54; no. 4; pp. 782 - 792
• Main Authors: Ranganathan, K., Walker, W.F.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustic signal processing; Acoustics; Algorithms; Apodization; Background noise; Biological and medical sciences; Biomedical imaging; Cysts; Design optimization; Electronics; Equipment Failure Analysis - methods; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Image Interpretation, Computer-Assisted - methods; Image resolution; Imaging; Investigative techniques, diagnostic techniques (general aspects); Laboratories; Measurement; Medical sciences; Medical simulation; Miscellaneous. Technology; Noise; Physics; Quality Control; Quantization; Reproducibility of Results; Scanners; Sensitivity and Specificity; Signal to noise ratio; Simulation; Ultrasonic imaging; Ultrasonic investigative techniques; Ultrasonography - instrumentation; Ultrasonography - methods; Ultrasound; Ultrasound imaging; Speckle; Background noise; Modeling; Image quality; AD converter; Wide band; Cyst; C scan; Medical imagery; Portable equipment; Acoustic image; Apodization; Signal to noise ratio
• ISSN: 0885-3010; 1525-8955
• DOI: 10.1109/TUFFC.2007.311

This paper describes a metric that can be used to characterize the resolution of arbitrary broadband coherent imaging systems. The metric is particularly suited to medical ultrasound because it characterizes scanner performance using the contrast obtained by imaging anechoic cysts of various sizes that are embedded in a speckle-generating background, accounting for the effect of electronic noise. We present the theoretical derivation of the metric and provide simulation examples that demonstrate its utility. We use the metric to compare a low-cost, handheld, C-scan system under development in our laboratory to conventional ultrasound scanners. We also present the results of simulations that were designed to evaluate and optimize various parameters in our system, including the f/# and apodization windows. We investigate the impact of electronic noise on our system and quantify the tradeoffs associated with quantization in the analog to digital converter. Results indicate that an f/1 receive aperture combined with 10-bit precision and a signal-to-noise ratio (SNR) of 0 dB per channel would result in adequate image quality