AUTOMATIC IDENTIFICATION OF ISOLATED CALCIFICATIONS AND THEIR ACCUMULATIONS ON MAMMOGRAMS

Abstract

Although microcalcinates usually are hyperattenuated, which makes them hyperintensive on mammograms, breast cancer is characterized by their small size, which, combined with the small size of their clusters, makes it difficult to identify them, especially against a dense background, which is often noted in fibrous changes in the breast parenchyma. The purpose of the study is to create and evaluate the effectiveness of the block for automatic identification of calcifications and their accumulations on mammograms. Material and methods. Mammograms of patients with suspicious (136 mammograms of 67 patients), as well as benign (299 mammograms of 151 patients) calcifications of various types were analyzed using a proprietary software package. Research results. After analyzing benign calcifications, the system marked all cases (100%) of calcified sediment, rod-shaped, vascular calcifications; 33 out of 36 (92.7%) cases of dystrophic, 66 out of 70 cases (94.3%) of rounded and 12 out of 15 (80%) cases of point calcifications in all patients; as well as 2 out of 3 cases of cutaneous calcifications in 1 out of 2 patients, 103 out of 106 (97.2%) cases of flaky calcifications in 51 out of 52 (98.1%) patients and 19 out of 22 cases (86.4%) of eggshell type calcifications in 10 out of 11 patients (90.9%). Among suspicious calcifications, the system marked 33 out of 39 cases (84.6%) of large heterogeneous calcifications, all 6 cases of small linear branching calcifications and 37 out of 39 (94.9%) cases of small polymorphic calcifications in all patients, as well as 30 out of 36 (83.3%) cases of amorphous calcifications in 15 out of 16 (93.7%) patients and 12 out of 16 (75.0%) cases of small linear calcifications in 6 out of 8 (75.0%) patients. All cases of unmarked suspicious calcifications corresponded to high-intensity soft-tissue shadows associated with indistinctly defined calcifications, which were labeled by the MammCheck II system previously developed by the authors. The frequency of false positive labels was 0.31 per mammogram. Conclusions. Benign calcifications were marked on 282 out of 299 images (94.3%) in 148 out of 151 (98.0%) patients, suspicious calcifications – on 118 out of 136 images (86.8%) in 64 out of 67 patients (95.5%).