Contralateral subtraction: a novel technique for detection of asymmetric abnormalities on digital chest radiographs.


Journal Article

A novel contralateral subtraction technique has been developed to assist radiologists in the detection of asymmetric abnormalities on a single chest radiograph. With this method, the lateral inclination is first corrected by rotating and shifting the original chest image so that the midline of the thorax is aligned with the vertical centerline of the original chest image. The rotated image is then flipped laterally to produce a reversed "mirror" image. Finally, the mirror image is warped and subtracted from the original image for derivation of the contralateral subtraction image. The three key techniques which are employed in this study are applied successively to the initial contralateral subtraction technique for acquisition of improved subtraction images. One hundred PA chest radiographs, including 50 normals and 50 abnormals, were used as the database for this study. The percentage of chest images, which were rated as being adequate, good, or excellent quality of subtraction images by employing a subjective evaluation method, was improved from 73% to 91% by use of the three key techniques. The contralateral subtraction technique can be used for detection of any asymmetric abnormalities, such as lung nodules, pneumothorax, pneumonia, and emphysema, on a single chest radiograph, and therefore has potential utility in a high proportion of abnormal cases.

Full Text

Duke Authors

Cited Authors

  • Li, Q; Katsuragawa, S; Ishida, T; Yoshida, H; Tsukuda, S; MacMahon, H; Doi, K

Published Date

  • January 2000

Published In

Volume / Issue

  • 27 / 1

Start / End Page

  • 47 - 55

PubMed ID

  • 10659737

Pubmed Central ID

  • 10659737

International Standard Serial Number (ISSN)

  • 0094-2405

Digital Object Identifier (DOI)

  • 10.1118/1.598856


  • eng

Conference Location

  • United States