Computer aided diagnosis for pulmonary nodules by extracting new shape features from X-ray CT images

In this paper, we propose a new diagnosis method of pulmonary nodules in CT images to reduce false positive(FP) rate under high true positive (TP) rate conditions. An essential core of the method is to extract two novel and effective features from the raw CT images: One is orientation features of nodules in a region of interest (ROI) extracted by a gabor filter, while the other is variation of CT values of the ROI in the direction along body axis. Simulation results show that the discrimination rate of the proposed method is extremely improved compared with that by the conventional method.