Abstract: Background and purpose: Contrast-enhanced spectral mammography (CESM) is a new technology introduced in recent years, and a technique based on conventional mammography. The radiation dose of the CESM was analyzed by comparing the average gland dose (AGD) of the low energy imaging and the CESM. Methods: A total of 143 patients with clinically palpable breast masses were enrolled in this study. The AGD of the two imaging methods were analyzed according to the type of breast glands (7 cases of almost entirely fatty type, 31 cases of scattered areas of fibroglandular density type, 76 cases of heterogeneously dense type, 29 cases of extremely dense type), lesion site (70 cases of right breast mass, 64 cases of left breast mass, 9 cases of bilateral breast mass) and age distribution (<40 years in 27 cases, 41-50 years in 51 cases, 51-60 years in 50 cases, 61-70 years old in 15 cases). Results: The AGD of
CESM of all the 143 patients was higher (26.22% ) than that of low energy imaging (P<0.05). The AGD of the four gland types of a, b, c and d in the CESM group were higher than those in the low energy imaging group by 26.05%, 25.92%, 26.82% and 24.93% respectively. Therefore the AGD of c-type gland increased the most, whereas AGD of d-type gland increased the least (P<0.05). The AGD of the affected side breast (4.15%) was higher than that of the unaffected side breast (P<0.05). There were statistically significant differences between the two groups by age (41-50 years, 51-60 years) (P<0.05). Conclusion: Radiation dose of CESM is slightly higher than that of low energy imaging in general and differences by breast gland types, lesion site and age can be observed. However, CESM is still a safe and reliable diagnostic imaging technology and can be applied according to clinical needs.

Key words: Contrast-enhanced spectral mammography, Full field digital mammography, Average gland dose, Radiation dosage