Analysis of Average Glandular Dose (AGD) and Associated Parameters for Conventional and Digital X-Ray Mammography

In this study, we determined the average glandular dose (AGD) from the craniocaudal (CC) and mediolateral oblique (MLO) views of 496 breasts (247 women) at eight clinics in Sudan. The incident air kerma from the X-ray tube output values and typical patient-specific breast exposure factors were measured. AGD values were inferred from the measured incident air kerma and breast-specific dose conversion coefficients. The AGD per CC and MLO projection and per woman ranged from 0.34–5.3 mGy (average: 2.46), 0.29–3.39 mGy (average: 1.50), and 0.6–7.4 mGy (average: 3.95). The proposed national diagnostic reference levels (mGy) are 3.48, 2.03, and 6.44 mGy for CC, MLO, and per woman, respectively. Establishing the proposed diagnostic reference levels is an essential step in ensuring patient protection from radiation and will help promote dose optimization for X-ray mammography at the national levels and beyond. The results provide important baseline data that can be used to formulate the national diagnostic reference levels.

Guiding vacuum-assisted biopsy in prone position: digital breast tomosynthesis vs stereotactic

Purpose: To compare the performance of prone digital breast tomosynthesis (DBT)–vacuum-assisted biopsy (VAB) with prone stereotactic-guided VAB (sVAB), focusing on time of procedure, number of expositions, average glandular dose, and complications. Methods: The institutional review board approved this retrospective study and informed consent was waived. From July 2015 to January 2017, 306 patients with 306 suspicious mammographic findings (BI-RADS ⩾4) underwent mammography-guided biopsy, prone sVAB, or prone DBT-VAB. Student t test, chi-square, and multivariate regression statistics were used. Results: During the study period, 155 prone sVAB procedures in 155 patients (mean age, 56 years; age range, 39–84 years) and 151 DBT-VABs in 151 patients (mean age, 57 years; age range, 33–84 years) were performed. Mean procedure time was shorter with DBT-VAB versus sVAB (14.5 versus 17.4 minutes, respectively; p < 0.001), and fewer images were acquired with DBT-VAB versus sVAB (8 vs 11, respectively; p < 0.001); the average glandular dose was significantly lower in DBT-VAB versus sVAB (11.8 mGy versus 18 mGy, respectively; p < 0.001). There were no differences in the distribution of histologic results ( p = 0.74) or breast density ( p = 0.09) between the two groups. No major complications were observed in either group. Conclusion: Performance of prone DBT-VAB was superior to prone sVAB because it allowed a faster procedure with fewer radiologic expositions and lower radiation dose.

Association of the Differences in Average Glandular Dose with Breast Cancer Risk

Objectives. To compare the differences in normalized average glandular dose (NAGD) between the breasts of healthy subjects and those of cancer patients and to determine if the NAGD difference is associated with breast cancer risk and improves breast cancer classification. Materials and Methods. Craniocaudal view and mediolateral view full-field digital mammography (FFDM) images were obtained from 1682 healthy subjects whose breasts were categorized as Breast Imaging-Reporting and Data System (BI-RADS) I or II and from 811 biopsy-confirmed unilateral breast cancer patients whose breasts on the contralateral side were category I or II. Both populations were randomized into training and test sets. Multivariate logistic regression analysis was used to build the breast cancer risk assessment model, and the area under the receiver operating characteristic curve ( A z ) was used to evaluate the model. Twenty-two breast cancer patients who were originally categorized as BI-RADS I or II for both breasts, but were diagnosed with unilateral biopsy-confirmed breast cancer subsequently, were included to validate the model. Results. The NAGD differences in both FFDM images between tumor-bearing breasts and the healthy breasts of patients were significantly higher than those in healthy subjects ( P < 0.001 ). The model with NAGD differences had a higher A z value than the model without NAGD differences. While there was no NAGD differences between originally healthy breasts of breast cancer patients, significant NAGD differences between now tumor-bearing breasts and the then previously healthy breasts were found in both FFDM images. Conclusions. NAGD differences between both breasts can be included in the breast cancer risk assessment model to evaluate breast cancer risk.

HOW DOES THE REDUCTION OF GLANDULAR TISSUE EFFECT THE FORCE AND BREAST THICKNESS IN MAMMOGRAPHY?

Purpose: To determine whether breast thickness decreases with menopause after the reduction of glandular tissue. We also wanted to know how the decrease in breast thickness affects the compression force and the average glandular dose. Methods: In this project, we collected data regarding the compression force, breast thickness and mean glandular dose of 300 patients who had mammographic imaging in two views: CC (craniocaudal) and MLO (mediolateral oblique) view. The data were divided into three age groups: 100 patients aged 50 to 55, 100 patients aged 60 to 65 and 100 patients aged 70 to 75 years. We used basic statistical tests for measurement purposes, while we used the Shapiro–Wilk test to check normality and the Kruskal–Wallis test to compare the differences. Results and discussion: We presented the results and comparisons in the tables and box plot graphs for CC and MLO views of the left and right breast for compression force, breast thickness and MGD. In the CC view of the both breasts, we found that there were statistically signifi cant differences in thickness between groups 1 and 3, and differences in MGD between groups 1 and 2, and 1 and 3. In the MLO view of both breasts we found that compression force does not increase with the age of patients, which can be attributed to the different size and density of breasts, and different compression force. Higher compression force results in lower MGD and breast thickness. Conclusion: In the CC view of left and right breast, there is no statistically signifi cant differences in compression force, but thickness and MGD changed between some groups. In the MLO view, only MGD changed. For further research, we recommend taking measurements on a larger sample, and concurrently considering and examining other factors that may affect breast thickness, compression force and MGD.

EVALUATION OF RADIATION DOSE FOR PATIENTS UNDERGOING MAMMOGRAPHY IN QATAR

In the absence of information on radiation doses in mammography in the Gulf countries, this study was designed to assess patient dose in terms of entrance surface air kerma and average glandular dose (AGD) in three mammography units in Qatar that covers 21% of all mammography systems in the country. The study of 150 patients involving 600 projections indicated that the average value of AGD in patients was 2.2 mGy for cranio-caudal and 2.5 mGy for mediolateral-oblique views, respectively. Dose assessment was also performed for polymethyl methacrylate phantoms of thicknesses, ranging from 20 to 80 mm. Comparing the patient dose values with several other publications in literature for full-field digital mammography, our values are typically higher, which can be likely attributed to the larger compressed breast thickness.

The parametric comperison of digital synthetic mammography with tomosynthesis and standard mammography

Cilj: Osnovni cilj našeg istraživanja je usporedba doznih parametara i debljine komprimirane dojke kod mamografskog pregleda koji je izvršen digitalnom tomosintezom (engl. digital breast thomosynthesis; DBT) i standardne, 2D mamografije. Ispitanici i metode: U istraživanje je uključeno 200 ispitanica životne dobi od 40 do 81 godine (median 60,5 ± 10,6). Ispitanice su podijeljene u dvije skupine, ovisno o vrsti mamografskog pregleda. Ova retrospektivna analiza obuhvatila je pretrage koje su vršene na mamografskom uređaju Hologic Selenia Dimensions (Hologic, Bedford, Mass) u razdoblju od 1. veljače 2018. do 30. ožujka 2018. Rezultati: Hi-kvadrat testom isključila se statistički značajna razlika u gustoći parenhima dojki između dviju grupa ispitanica. T-test nije pokazao statistički značajnu razliku u dobi ispitanica, kao niti razlike u debljini komprimiranih dojki između dviju ispitanih skupina. Vrijednost srednje glandularne doze (engl. average glandular dose; AGD) kod DBT-a u odnosu na 2D mamografiju bila je viša 0,53 mGy za lijevu dojku, a 0,37 mGy za desnu dojku (3,83 / -1 mGy, p = 0.001; 3.82 / -0.9 mGy, p = 0.023). Zaključak: Usprkos statistički značajnoj razlici u AGD-u kod DBT-a u odnosu na 2D mamografiju između dviju skupina ispitanica, ona je unutar granica prihvatljivosti propisanih Pravilnikom o uvjetima za primjenu izvora ionizirajućeg zračenja u svrhu medicinskog i nemedicinskog ozračenja (NN 42/2018, 9. 5. 2018.), stoga smatramo da je opravdano uvođenje DBT-a kao standardne radiološke metode pregleda dojki.

Patient-Assisted Compression in Screening Mammography: Patient Experience and Image Quality

Objective Screening mammography is critical to reduce breast cancer mortality, yet many women cite pain from compression as a reason they avoid this test. We evaluated patient experience and image quality in screening patients opting for a handheld patient-assisted compression (PAC) device. Methods After institutional review board approval, women screened between February and July 2018 with a synthetic 2D/tomosynthesis mammography unit were offered use of a handheld PAC device. Patient experience through survey, image quality, compression thickness, compression force, and average glandular dose were evaluated and compared between women opting for PAC and women opting for technologist-controlled compression (TC). Multivariable ordinal logistic and linear regression models were estimated to control for age and breast density. In addition, for women opting for PAC, image quality obtained with their current PAC mammogram was compared with that obtained with their prior TC mammogram, by using Wilcoxon/Pearson tests. Results Seventy-three percent of women preferred their mammogram experience with PAC compared with their prior mammogram without PAC. Women using PAC reported decreased anxiety compared with those using TC, after controlling for age and breast density (adjusted odds ratio [aOR] 0.22 [95% confidence interval (CI): 0.09–0.49]). There were no significant differences in image quality, compression thickness, or average glandular dose in exams for women using PAC compared with exams for women using TC. Women using PAC had significantly more compression force than women using TC had (P = 0.012). Conclusions Mammography with PAC improves patient experience and results in similar image quality compared with mammography with TC.