New display mode for emphasizing concentration of fold patterns in virtual gastrocsocpy

Abstract

This paper presents a new display mode for virtual gastroscopy that shows suspicious regions as cancers by visualizing the degree of concentration of stomach fold patterns. In diagnosis of the stomach, local concentration of stomach folds is one of important signs of cancer. Therefore, if such fold concentration can be displayed on virtual gastroscopic images, it is very useful for diagnosis. In the paper, we propose a procedure for quantifying local concentration of folds on the stomach wall, and for displaying the results on virtual gastroscopy. A morphological operation is employed for extraction of fold regions from 3-D abdominal X-ray CT images. Also, a shape feature called Concentration Index (CI) is used for quantifying local concentration at each point on the stomach wall in a 3-D abdominal X-ray CT image. The procedure consists of following four major steps: (1) extraction of stomach fold regions from CT images; (2) projection of the fold pattern onto local tangent planes; (3) computation of CI at each point on the stomach wall; and (4) visualization of the results on virtual gastroscpic images. In the experiments using real abdominal CT images, it was shown that by using the new display mode, suspicions regions could be easily observed on the virtual gastroscopy.