It is hard to detect lung nodules automatically from CT images for lung CAD system. A detection algorithm is proposed for solitary pulmonary nodules(SPNs) in thoracic CT images in this paper. Firstly
lung field is segmented from original CT image effectively and accurately. Secondly
areas of local maximum gray are found
to segment regions of interest(ROIs) roughly. Then
features of each ROI are extracted
each feature is described quantitatively by the accuracy of SVM classification with each single feature separately
and Mahalanobis distance is weighted by the quantitative parameters. Finally
ROIs are classified to nodule or non nodule with the improved Mahalanobis distance. Experiment results indicated that the algorithm can detect SPNs effectively
it is with relatively high sensitivity and low false neglected rate
and it can provide doctors helpful information to diagnose lesions in early stage of lung cancer.