Forma, Vol. 13 (No. 3), pp. 233-245, 1998
Original Paper

Three Dimensional Concentration Index as a Feature of Line Pattern Distribution in Three Dimensional Space

Yasushi Hirano1, Yoshito Mekada2, Jun-ichi Hasegawa3 and Jun-ichiro Toriwaki4

1Graduate School of Engineering, Nagoya University, Nagoya 464-8603, Japan
2Faculty of Engineering, Utsunomiya University, Utsunomiya 321-8585, Japan
3School of Computer and Cognitive Sciences, Chukyo University, Toyota 470-0393, Japan
4Faculty of Engineering, Nagoya University, Nagoya 464-8603, Japan

(Received July 21, 1998; Accepted February 3, 1999)

Keywords: 3D Concentration Index, Pattern Analysis, 3D Image Processing, Computer Aided Diagnosis, X-ray CT Image

Abstract. This paper proposes a new shape feature called three dimensional (3D) concentration index for analyzing local concentration of 3D line patterns. The 3D concentration index is conceptually an expansion of the 2D concentration index to 3D space. The 2D concentration index was used for detecting cancer lesions with local concentration of folds on the stomach wall in double contrast stomach X-ray images. In this paper, the basic properties of 3D concentration index are studied with simulations. Furthermore, we apply it to real chest X-ray CT images, and confirm its usefulness for the discrimination between benign and malignant lung tumor shadows.