Delineation of tagged region by use of local iso-surface roughness in electronic cleansing for CT colonography

Wenli Cai; Hiroyuki Yoshida; Michael Zalis; Janne Näppi

doi:10.1117/12.710088

29 March 2007 Delineation of tagged region by use of local iso-surface roughness in electronic cleansing for CT colonography

Wenli Cai, Hiroyuki Yoshida, Michael Zalis, Janne Näppi

Author Affiliations +

Proceedings Volume 6514, Medical Imaging 2007: Computer-Aided Diagnosis; 651409 (2007) https://doi.org/10.1117/12.710088
Event: Medical Imaging, 2007, San Diego, CA, United States

Abstract

Electronic cleansing (EC) is an emerging method for segmentation of fecal materials, which are tagged by an X-ray-opaque oral contrast agent in CT colonography (CTC) images, effectively removing them for digital cleansing of the colon. Due to the partial volume effect, voxels at the boundary between the lumen and tagged materials, called the L-T boundary, not only have CT values that are close to those of soft-tissue structures, but also have gradient values that are similar to a thin soft-tissue structure that is sandwiched between the tagged region and the lumen, which we call a tagging-tissue-air layer. Degradation of thin colonic wall and folds, as well as creation of pseudo soft-tissue structures at the periphery of tagged regions, are main artifacts in existing EC approaches, which tend to use a gradient-based method to delineate tagged regions. In this study, we developed a novel delineation method of tagged regions by applying local iso-surface roughness. The local iso-surface roughness is defined by the sum of differences between the local curvedness at adjacent scales over all scales. In our approach, the roughness values around the periphery of the tagged regions are integrated into the speed function of a level-set segmentation method for delineation of the tagged regions. As a result, L-T boundaries are subtracted along with tagged regions, whereas the thin soft-tissue structures within the tagging-tissue-air layers are preserved. Application of our computer-aided detection (CAD) scheme showed that the use of the new EC method substantially reduced the number of false-positive detections compared with that of our previous gradient-based method.

Citation Download Citation

Wenli Cai, Hiroyuki Yoshida, Michael Zalis, and Janne Näppi "Delineation of tagged region by use of local iso-surface roughness in electronic cleansing for CT colonography", Proc. SPIE 6514, Medical Imaging 2007: Computer-Aided Diagnosis, 651409 (29 March 2007); https://doi.org/10.1117/12.710088

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available