A Multi-Scale Matched Filter for Nodule Detection in Chest X-Ray Radiography

A multi-scale matched filter based on Hotelling classifier is presented to improve the accuracy of nodule detection in chest X-ray radiography.The positive and negative radiography samples are used to train multi-dimension matched filters by Hotelling model.The visual detection difference is calculated using the filter outputs of radiography,and the optimal dimension filter is searched subject to the maximum detection difference.Then the nodule size and detection capability are calculated based on the optimal filter.Experimental results show that there is good accordance of the detection performances between the presented method and subjective observers.The method improves the detection accuracy and reduces the false-positive regions in the processed images.Errors of the calculated relative nodule sizes mainly distribute between-0.21 and 0.18 and the proportion of the images in this range is 86%.