Development of CAD prototype system for Crohn's disease

Abstract

The purpose of this paper is to present a CAD prototype system for Crohn's disease. Crohn's disease causes inflammation or ulcers of the gastrointestinal tract. The number of patients of Crohn's disease is increasing in Japan. Symptoms of Crohn's disease include intestinal stenosis, longitudinal ulcers, and fistulae. Optical endoscope cannot pass through intestinal stenosis in some cases. We propose a new CAD system using abdominal fecal tagging CT images for efficient diagnosis of Crohn's disease. The system displays virtual unfolded (VU), virtual endoscopic, curved planar reconstruction, multi planar reconstruction, and outside views of both small and large intestines. To generate the VU views, we employ a small and large intestines extraction method followed by a simple electronic cleansing method. The intestine extraction is based on the region growing process, which uses a characteristic that tagged fluid neighbor air in the intestine. The electronic cleansing enables observation of intestinal wall under tagged fluid. We change the height of the VU views according to the perimeter of the intestine. In addition, we developed a method to enhance the longitudinal ulcer on views of the system. We enhance concave parts on the intestinal wall, which are caused by the longitudinal ulcer, based on local intensity structure analysis. We examined the small and the large intestines of eleven CT images by the proposed system. The VU views enabled efficient observation of the intestinal wall. The height change of the VU views helps finding intestinal stenosis on the VU views. The concave region enhancement made longitudinal ulcers clear on the views.