Computer-aided diagnosis of pulmonary nodules based on shape analysis using thin-section CT images

Characterization of pulmonary nodules plays a significant role in the differential diagnosis of lung cancer. This paper presents a method to characterize the internal structure of small pulmonary nodules through curvature-based descriptor using thin-section CT images. The present work is a first step toward the segmentation of the three-dimensional (3D) nodule images by using a 3D deformable surfaces approach. Second, a curvature-based representation of the pulmonary nodule is derived. Based on this representation, the pulmonary nodules are globally characterized through the shape spectra. This quantification emphasizes the difference between benign and malignant pulmonary nodules surroundings. Experiments on true 3D nodule images demonstrate good performance of our curvature based analysis technique.