Impact of B-mode color encoding on rapid detection of ultrasound targets: an in vitro study

The purpose of this study was to assess the impact that new B-Mode color encoding schemes have on an observer's ability to rapidly detect ultrasound targets in an in vitro system. Four phantoms were created with five-, six-, or seven-tissue-density objects. Each phantom was scanned in routine grey scale (256 grey levels) and in three different color encoding algorithms. A test tape containing 3- and 5-second exposures, in random order, to the different phantoms recorded in grey and B-mode color was then prepared and viewed by 21 observers. Results were tabulated as the mean number of absolute errors in object recognition, per observer, per scan, for both the 3- and 5-second exposures. Each color scheme reduced observer detection error rates compared with error rates with grey scale recordings when viewed for 3 seconds. There was no reduction in error rates when 5-second exposures were viewed. We conclude that in an in vitro system, new B-mode color encoding schemes may facilitate rapid and accurate detection of soft-tissue targets.