Computerized assessment of tissue composition on digitized mammograms

Rationale and Objectives. The authors developed a computerized method for the quantitative assessment of breast tissue composition on digitized mammograms. Materials and Methods. Three radiologists were asked to review 200 digitized mammograms and independently provide a Breast Imaging Reporting and Data System-like rating for breast tissue composition on a scale of 0 to 4. These values were incorporated into a "consensus" rating that was used as a reference point in the development and evaluation of a computerized method. After tissue segmentation that excluded nontissue areas, a set of quantitative features was computed. A computerized summary index that attempts to reproduce the radiologists' ratings was developed. Correlation coefficients (Pearson r) were used to compare the computerized index with the consensus ratings. Results. Some individual features computed for the relatively dense breast areas showed good correlation (r>0.8) with the radiologists' subjective ratings. The summary index of tissue composition demonstrated a significant correlation (r=0.87), as well. Conclusion. Computerized methods that show good correlation with radiologists' ratings of breast tissue composition can be developed.