Are There Quantifiable Reasons for a Radiologist’s Preference for an Intensity Inverted Mammogram?

Abstract

Xeromammography was originally used in preference to conventional mammography because radiologists preferred the sharper images in which fibroglandular tissue appeared as regions of low intensity [1]. However, due to the larger radiation dose involved xeromammography was soon replaced by conventional screen/film mammography in which fibroglandular tissue occupies the higher intensity range within the image. With the wider acceptance of computer manipulation of mammographic images it is now a trivial operation to intensity invert a conventional digitised mammogram to display it in a similar way to the xeromammogram. In the authors experience radiologists shown the intensity inverted image alongside the conventional image unanimously prefer the inverted image. Justification by the radiologists for this preference suggests that features and structure within the intensity inverted image appear’ sharper’ or better defined than in the conventional image. This study describes an effort to confirm this observation by examining the variation in perception of shapes of masses in both intensity inverted and conventional mammograms.