Computer-Aided Diagnosis in Mammography Using Content-based Image Retrieval Approaches: Current Status and Future Perspectives

Abstract

As the rapid advance of digital imaging technologies, the content-based image retrieval (CBIR) has became one of the most vivid research areas in computer vision. In the last several years, developing computer-aided detection and/or diagnosis (CAD) schemes that use CBIR to search for the clinically relevant and visually similar medical images (or regions) depicting suspicious lesions has also been attracting research interest. CBIR-based CAD schemes have potential to provide radiologists with "visual aid" and increase their confidence in accepting CAD-cued results in the decision making. The CAD performance and reliability depends on a number of factors including the optimization of lesion segmentation, feature selection, reference database size, computational efficiency, and relationship between the clinical relevance and visual similarity of the CAD results. By presenting and comparing a number of approaches commonly used in previous studies, this article identifies and discusses the optimal approaches in developing CBIR-based CAD schemes and assessing their performance. Although preliminary studies have suggested that using CBIR-based CAD schemes might improve radiologists' performance and/or increase their confidence in the decision making, this technology is still in the early development stage. Much research work is needed before the CBIR-based CAD schemes can be accepted in the clinical practice.

Figure 1

Illustration of a CAD scheme using the CBIR approach.

Figure 2

Example of applying a CAD scheme using CBIR approach to detect and classify a suspicious breast mass region. A suspicious mass is automatically detected by CAD scheme and queried by the observer (pointed by the arrow). In CAD workstation, the mass region segmentation (boundary contour), 12 CBIR-selected similar ROIs, and both detection and classification scores are displayed. Among the 12 similar ROIs, 8 depict malignant masses (marked by Red frame), 2 depict benign masses (marked by Green frame), and 2 depict CAD-cued false-positive regions (marked by Blue frame).