Method and system for automated selection of regions of interest and detection of septal lines in digital chest radiographs

A computer system for automated detection of abnormalities in digital chest radiographs, comprising:

• means for identifying peripheral lung areas of a digital chest radiograph to be analyzed;
• means for preselecting a sample of numerous contiguous regions of interest (ROIs) included in said peripheral lung areas;
• means for performing a background trend correction on each of the ROIs of said preselected sample so as to produce corrected image data;
• means for performing an edge gradient analysis on each of the ROIs of said preselected sample in order to distinguish sharp-edged ROIs from ROIs without sharp edges;
• means for removing a portion of said sharp-edged ROIs from said preselected sample;
• and
• means for performing texture measurements on the remaining ROIs of said preselected sample which have not been removed in said removing step.

A computer implemented method for automated detection of septal lines in a digital chest radiograph, stored in an image memory in a computer, comprising:

• identifying a lower lung area along rib cage edges in said digital chest radiograph;
• preselecting, using said computer, a sample of numerous contiguous regions of interest (ROIs) within said lower lung area;
• performing contrast enhancement, in said computer, using an unsharp masking technique with a rectangular mask;
• removing a background trend from each individual ROI;
• calculating accumulated edge gradients for each of said individual ROIs;
• generating an edge-gradient orientation histogram, in said computer, for each of said individual ROIs based on said calculated accumulated edge gradients;
• comparing, using said computer, each generated edge-gradient orientation histogram with predetermined values stored in a database to obtain a comparison result for each of said individual ROIs;
• determining if septal lines are present in each of said individual ROIs based on said comparison result for each of said individual ROIs;
• and
• classifying, using said computer, each of said individual ROIs as normal or abnormal having septal lines.

A computer system for automated detection of septal lines in digital chest radiographs, comprising:

• means for identifying a lower lung area along rib cage edges;
• means for preselecting a sample of numerous contiguous regions of interest (ROIs) within said lower lung area;
• means for performing contrast enhancement using an unsharp masking technique with a rectangular mask;
• means for removing a background trend from each individual ROI;
• means for calculating accumulated edge gradients for each of said individual ROIs;
• means for generating an edge-gradient orientation histogram for each individual ROI based on said calculated accumulated edge gradients;
• means for comparing each generated edge-gradient orientation histogram with predetermined values stored in a database to obtain a comparison result for each individual ROI;
• means for determining if septal lines are present in each of said individual ROIs based on said comparison result for each of said individual ROIs;
• and
• means for classifying each of said individual ROIs as normal or as abnormal having septal lines.