乳腺癌显示的最佳摄影位置及质量控制

目的评价显示乳腺癌的最佳位置及质量控制方法。方法随机抽取88例经X线诊断、病理证实为乳腺癌的MLO位和CC位照片，对其病灶在两个位置上的显示情况和MLO位的影像质量进行回顾性分析，探讨乳腺摄影的最佳位置和质控方法。结果MLO位显示率为98．86％，CC位显示率为82．95％；影像质量合格率为64．77％，诊断符合率为100％。结论MLO位是乳腺癌显示的最佳位置，其质量控制的关键是摆位和压迫。     

Can radiographers read screening mammograms?

AIM: To evaluate the ability of radiographers to read screening mammograms in the National Health Service Breast Screening Programme (NHSBSP). MATERIALS AND METHODS: Two radiographers read a test set of 1000 screening mammograms previously reported by a consultant radiologist. Three radiographers then acted as a second reader for 54,000 screening mammograms, their recall results are presented. Four consultant radiologists and three film reading radiographers were timed while reading 2500 mammograms each. RESULTS: When reading the test mammograms the two radiographers recalled all the cancers previously detected by the radiologist at the original screen read. They also recalled 32/90 women who subsequently presented with interval cancers. As a second reader the radiographers had similar recall and cancer detection rates to the radiologists (P>0.05). Double reading detected 9% more cancers. The radiographers take the same length of time to film read as radiologists (P>0.05). CONCLUSION: Radiographers are able to read screening mammograms at least as well as radiologists and do not take longer to do so.     

Compression force variability in mammography in Ghana – A baseline study

IntroductionBreast compression during mammographic examinations improves image quality and patient management. Several studies have been conducted to assess compression force variability among practitioners in order to establish compression guidelines. However, no such study has been conducted in Ghana. This study aims to investigate the compression force variability in mammography in Ghana.MethodsThis retrospective study used data gathered from 1071 screening and diagnostic mammography patients from January, 2018–December, 2019. Data were gathered by seven radiographers at three centers. Compression force, breast thickness and practitioners' years of work experience were recorded. Compression force variability among practitioners and the correlation between compression force and breast thickness were investigated.ResultsMean compression force values recorded for craniocaudal (CC) (17.2 daN) and mediolateral oblique (MLO) (18.2 daN), were within the recommended values used by western countries. Most of the mammograms performed – 80% – were within the National Health Service Breast Screening Programme (NHSBSP) range. However, 65% were above the Norwegian Breast Cancer Screening Programme (NBCSP) range. Compression forces varied significantly (p = 0.0001) among practitioners. Compression forces increased significantly (p = 0.0001) with the years of work experience. A weak negative correlation (r = ?0.144) and a weak positive correlation (r = 0.142) were established between compression force and breast thickness for CC and MLO projections respectively.ConclusionThis initial study confirmed that although wide variations in compression force exist among practitioners in Ghana, most practitioners used compression forces broadly within the range set by the NHSBSP. As no national guidelines for compression force currently exist in Ghana, provision of these may help to reduce the range of variations recorded.Implications for practiceConfirmation of variations in compression will guide future practice to minimize image quality disparities and improve quality of care.     

3D localization of clustered microcalcifications using cranio-caudal and medio-lateral oblique views.

This paper presents a 3D localization method to register clustered microcalcifications on mammograms from cranio-caudal (CC) and medio-lateral oblique (MLO) views. The method consists of three major components: registration of clustered microcalcifications in CC and MLO views, 3D localization of clustered microcalcifications and 3D visualization of clustered microcalcifications. The registration is performed based on three features, gradient, energy and local entropy codes that are independent of spatial locations of microcalcifications in two different views and are prioritized by discriminability in a binary decision tree. The 3D localization is determined by a sequence of coordinate corrections of calcified pixels using the breast nipple as a controlling point. Finally, the 3D visualization implements a virtual reality modeling language viewer (VRMLV) to view the exact location of the lesion as a guide for needle biopsy. In order to validate our proposed 3D localization system, a set of breast lesions, which appear both in mammograms and in MR Images is used for experiments where the depth of clustered microcalcifications can be verified by the MR images.     

A preliminary report on the role of spatial frequency analysis in the perception of breast cancers missed at mammography screening

RATIONALE AND OBJECTIVES: Because several factors are involved in cancer detection, a malignant lesion that is visible on a mammogram will not necessarily be reported by the radiologist reading the case. Indeed, a significant fraction of screening-detected cancers are visible in retrospect, and were perceived by the radiologist when the case was read, but were either reported as benign findings or dismissed as variations of normal breast tissue. In this preliminary report the spatial frequency characteristics of clinically missed lesions are investigated by analyzing the mammogram acquired when the lesion was sent for biopsy and the most recent prior mammogram. For control purposes, the contralateral breast is also analyzed, when this breast is lesion free. MATERIALS AND METHODS: A database of 70 mammogram cases was assembled. Each case contained eight films: craniocaudal (CC) and mediolateral oblique (MLO) of the breast where a biopsy-proven lesion was found, CC and MLO of the contralateral breast, and CC and MLO of both breasts in the most recent prior mammogram. The dictated reports for all of these cases were obtained. Both benign and malignant lesions were used. The films were digitized and an region of interest surrounding each lesion was segmented from the image for processing using wavelet packets to extract spatial frequency information. The corresponding area was also segmented from the prior mammogram and from the contralateral breast, when this breast was lesion-free. Analysis of variance was used to determine if statistically significant differences existed between the derived features of cancer in the current and prior mammograms. RESULTS: The data suggests that malignant lesions reported in the prior mammogram as being benign differed from correctly reported malignant lesions and from correctly reported benign lesions. They also differed from nonreported malignant lesions. In addition, the spatial frequency representation of cancer significantly differed in the current and prior cases from the representation of normal breast tissue. CONCLUSION: Spatial frequency analysis may be useful to differentiate malignant lesions that are reported as benign and correctly reported benign lesions.     

Reproducibility of Computer-Aided Detection Marks in Digital Mammography

Objective

To evaluate the performance and reproducibility of a computer-aided detection (CAD) system in mediolateral oblique (MLO) digital mammograms taken serially, without release of breast compression.

Materials and Methods

A CAD system was applied preoperatively to the full-field digital mammograms of two MLO views taken without release of breast compression in 82 patients (age range: 33 - 83 years; mean age: 49 years) with previously diagnosed breast cancers. The total number of visible lesion components in 82 patients was 101: 66 masses and 35 microcalcifications. We analyzed the sensitivity and reproducibility of the CAD marks.

Results

The sensitivity of the CAD system for first MLO views was 71% (47/66) for masses and 80% (28/35) for microcalcifications. The sensitivity of the CAD system for second MLO views was 68% (45/66) for masses and 17% (6/35) for microcalcifications. In 84 ipsilateral serial MLO image sets (two patients had bilateral cancers), identical images, regardless of the existence of CAD marks, were obtained for 35% (29/84) and identical images with CAD marks were obtained for 29% (23/78). Identical images, regardless of the existence of CAD marks, for contralateral MLO images were 65% (52/80) and identical images with CAD marks were obtained for 28% (11/39). The reproducibility of CAD marks for the true positive masses in serial MLO views was 84% (42/50) and that for the true positive microcalcifications was 0% (0/34).

Conclusion

The CAD system in digital mammograms showed a high sensitivity for detecting masses and microcalcifications. However, reproducibility of microcalcification marks was very low in MLO views taken serially without release of breast compression. Minute positional change and patient movement can alter the images and result in a significant effect on the algorithm utilized by the CAD for detecting microcalcifications.     

Accuracy of marker clip placement after mammotome breast biopsy.

OBJECTIVE: To assess, after stereotaxic, vacuum-assisted breast biopsy, the accuracy of marker clip deployment for guiding subsequent needle localization procedures and surgery. METHODS: We conducted a retrospective review of 100 vacuum-assisted core breast biopsies that were followed by marker clip deployment. Craniocaudal (CC) and mediolateral oblique (MLO) mammograms were used to locate clips relative to the centre of the target lesion in 5-mm increments. RESULTS: In the 94 of 100 cases adequate for review, maximum marker clip displacement of less than 10 mm on either the CC or MLO views was observed in 68 (72%) cases. In 9 (10%) cases, the localization clip was positioned more that 24 mm from the target lesion. CONCLUSION: Post-biopsy CC and MLO radiographs are recommended to identify those cases in which there is a significant difference between the location of the marker clip and the biopsied lesion.     

Screening Sensitivity According to Breast Cancer Location

PurposeTo examine the relation between breast cancer location and screening mammogram sensitivity, and assess whether this association is modified by body mass index (BMI) or breast density.MethodsThis study is based on all interval cancers (n = 481) and a random sample of screen-detected cancers (n = 481) diagnosed in Quebec Breast Cancer Screening Program participants in 2007. Film-screening mammograms, diagnostic mammograms, and ultrasound reports (when available) were requested for these cases. The breast cancer was then localised in mediolateral oblique (MLO) and craniocaudal (CC) projections of the breast by 1 experienced radiologist. The association between cancer location and screening sensitivity was assessed by logistic regression. Adjusted sensitivity and sensitivity ratios were obtained by marginal standardisation.ResultsA total of 369 screen-detected and 268 interval cancers could be localised in MLO and/or CC projections. The 2-year sensitivity reached 68%. Overall, sensitivity was not statistically associated with location of the cancer. However, sensitivity seems lower in MLO posterior inferior area for women with BMI ≥ 25 kg/m² compared to sensitivity in central area for women with lower BMI (adjusted sensitivity ratio: 0.58, 95% confidence interval [CI]: 0.17–0.98). Lower sensitivity was also observed in subareolar areas for women with breast density ≥ 50% compared to the central areas for women with lower breast density (for MLO and CC projections, adjusted sensitivity ratio and 95% CI of, respectively, 0.54 [0.13–0.96] and 0.46 [0.01–0.93]).ConclusionsScreening sensitivity seems lower in MLO posterior inferior area in women with higher BMI and in subareolar areas in women with higher breast density. When interpreting screening mammograms, radiologists need to pay special attention to these areas.     

Quality assurance of mammograms in the Norwegian Breast Cancer Screening Program

This study compared the proportion of mammograms classified as perfect, good, moderately good or inadequate by a radiographer specially trained for doing such a classification at a breast centre (local-PGMI radiographer) with the proportion similarly assessed by an expert-PGMI radiographer. The results were compared with the recommendations given in the quality assurance manual of the Norwegian Breast Cancer Screening Programme. The reasons for classifying the mammograms into other than perfect, such as good, moderately good or inadequate were investigated.The quality of the mammograms was measured by using the PGMI system, which is a quality-review model that classifies the images into the four categories according to positioning, compression, exposure, noise, artefacts, and movement. A total of 1280 mammograms from all 16 breast centres in the screening programme were classified.The distribution of perfect, good, moderately good, and inadequate mammograms differed between the local-PGMI radiographers and the expert radiographer, for both the cranio-caudal (CC) and mediolateral-oblique (MLO) mammograms (P < 0.001 for both). The expert radiographer classified a higher proportion of both CC (28%) and MLO (14%) mammograms as inadequate than did the local-PGMI radiographers (7% and 3%, respectively; P < 0.001 for both). The guidelines recommend ≤3% of the mammograms to be inadequate. The reason given for the inadequate classifications by the expert radiographer was predominantly “parts of the breast missing” for both the CC and the MLO mammograms.There is room to improve the quality of the mammograms in the screening programme in Norway. Attention should be given to positioning and the use of standardized terms in the PGMI classification.     

Proficiency test in clinical mammography. Results of a consecutive series of 130 volunteer Italian radiologists

PURPOSE: We evaluated the results obtained by 130 Italian radiologists undergoing a proficiency test of clinical mammography. MATERIAL AND METHODS: Radiologists were invited to report a series of 100 mammograms (two views), including 32 cancers and 78 non-cancers, with limited information regarding age, subjective symptoms, and findings at palpation. Sensitivity and specificity were then calculated. The test was validated by a panel of experts, and standards for test sufficiency were established on that basis (sensitivity > 80%, specificity > 85%). The tested radiologists differed by mammographic practice (average = 5.7 years, range 0.5-18), total number of mammograms read (average = 8,784, range 300-50,000) and per year (average = 1,535 range 300-5,000). RESULTS: Sensitivity (standard > 80%, average 81.1%, range 39-100%) and specificity (standard > 85%, average 84.0%, range 38-98%) standards were reached by 79 (60.8%) and 81 (62.3%) radiologists, respectively. Overall, only 37 (28.5%) radiologists passed the test (reached both standards). Mammographic practice (years of experience) (chi 2 for trend 5.26, p = 0.02), total mammograms read (chi 2 5.86, p = 0.05), and mammograms read per year (chi 2 8.07, p = 0.01) significantly correlated with a sufficient test. DISCUSSION: The evaluated sample is rather large but not necessarily representative of Italian radiologists. Had the sample been selected, there is no way to know if the results would have been biased towards a better or worse figure with respect to the national average. A significant correlation was found with reading experience (the best results were obtained by operators with > 10,000 films read and with > 2,000 films read/year), as which is important because most Italian radiologists reporting mammography usually read a limited number of cases. CONCLUSIONS: These results on such a wide sample of radiologists, possibly representative of the national average, are disappointing, and suggest that the average quality of mammography reporting in Italy may not be up to standards. Thus, we suggest that quality control program for clinical mammography not only test the equipment but include training and accreditation of radiologists.     

Reconstruction and rendering of microcalcifications from two mammogram views by modified projective grid space (MPGS).

Mammograms taken by two views: cranio-caudal (CC) and medio-lateral oblique (MLO) views provide only 2D projections of the microcalcifications, which lack the depth information. Thus, envisioning the relative lesion location from mammograms is a challenge for radiologists. To assist radiologists in locating and rendering lesion tissues, a modified projective grid space (MPGS) scheme is proposed to reconstruct 3D microcalcifications. The MPGS scheme reconstructs 3D microcalcifications in a unique space defined by corresponding points and the epipoles retrieved from the fundamental matrix of the CC and MLO views. Since only corresponding points of images are required in the proposed MPGS scheme, we can avoid the difficulty associated with most reconstruction approaches that require prior complicated calibration of X-ray machine. Considering the deformation of the breast, a new method based on the concept of bundle adjustment is proposed to rectify the 3D locations of reconstructed microcalcifications by uncompressed breast model reconstructed from the real patient body using MPGS scheme with iterative closest point (ICP). Then, the reconstructed microcalcifications are augmented in the real patient body model to show their relative positions.     

Variability of breast density assessment in short-term reimaging with digital mammography

Objective

To evaluate the variability of breast density assessments in short-term reimaging with digital mammography.

Materials and methods

In 186 women, short term (mean interval, 27.6 days) serial digital mammograms including CC and MLO views were obtained without any treatment. Mammographic density assessments were performed by three blinded radiologists for Breast Imaging Report and Data System (BI-RADS, grades 1–4) and visual percentage density (PD) estimation, and by one radiologist for computer-aided PD estimation. The variability of assessments was analyzed according to the age, breast density, and mammography types by multivariate logistic regression.

Results

In BI-RADS assessments, 29% (161 of 558) of breast density categories were assessed differently after short-term reimaging and the mean absolute difference in PD for CC and MLO view was 7.6% and 8.1% for visual assessments, and 7.4% and 6.4% for computer-aided assessments, respectively. Among all computer-aided assessments, 29% (54 of 186) of CC view and 22% (41 of 186) of MLO view assessments had discrepancy over 10% in PD. Younger age (<50), greater breast density (grades 3 and 4), and different mammography types were significantly associated with the variability.

Conclusion

Considerable variability in breast density assessments occurred in short-term reimaging with digital mammography, particularly in women with younger age and greater breast density and when examined using different types of mammography.     

Breast biphasic compression versus standard monophasic compression in X-ray mammography

Breast biphasic compression (22.5 degrees angled paddle, followed by progressive angle reduction) was compared with standard monophasic compression in x-ray mammography. The presence of the pectoral muscle was recorded for the craniocaudal (CC) view and the presence of the inframammary fold for the mediolateral oblique (MLO) view. The amount of breast in each study and image quality were assessed for both views. For all parameters, biphasic compression performed better than monophasic compression in both CC (P: <.006) and MLO (P: <.04) views.     

Should previous mammograms be digitised in the transition to digital mammography?

Breast screening specificity is improved if previous mammograms are available, which presents a challenge when converting to digital mammography. Two display options were investigated: mounting previous film mammograms on a multiviewer adjacent to the workstation, or digitising them for soft copy display. Eight qualified screen readers were videotaped undertaking routine screen reading for two 45-min sessions in each scenario. Analysis of gross eye and head movements showed that when digitised, previous mammograms were examined a greater number of times per case (p = 0.03), due to a combination of being used in 19% more cases (p = 0.04) and where used, looked at a greater number of times (28% increase, p = 0.04). Digitising previous mammograms reduced both the average time taken per case by 18% (p = 0.04) and the participants’ perceptions of workload (p < 0.05). Digitising previous analogue mammograms may be advantageous, in particular in increasing their level of use.     

Incident screening cancers detected with a second mammographic view: pathological and radiological features

Previous studies and epidemiological data from the UK National Health Service Breast Screening Programme (NHSBSP) have indicated significantly increased sensitivity for cancer detection with two-view rather than one-view mammographic screening. The radiological and pathological features of these extra cancers have not been previously reported in detail. We have studied all screen-detected cancers found as incident cases in the South West London Breast Screening Service between 1994-1997 on the second round of screening. To assess the effect of two-view versus one-view mammography on cancer detection, these cases were mixed with controls in a 1:2 ratio in nine test sets and each set read independently by three film readers. They initially read the oblique view, then the craniocaudal views, and recorded abnormalities on the films and likelihood of recall. Radiological and histological data were recorded for each case. Using two views, 8.9% (P < 0.05) more invasive cancers were detected. The sensitivity increase was highest for invasive cancers less than 10 mm (11%) and cancers of low grade (11.9%). These sensitivity increases may underestimate the increase in 'real life' because of over-recalling of normal mammograms, particularly with one view, under study conditions. The most significant radiological feature of invasive cancers was an irregular mass, which, seen on one view had a positive predictive value of 82.2% and 89.9% with two views. The craniocaudal view was helpful, firstly, because some cancers were not visible on the oblique view only. Secondly, benign appearing round masses and asymmetric densities seen with the oblique view only were resolved as more suspicious irregular masses with both views, leading to recall. In conclusion, there are cancers that cannot be adequately visualized on the oblique view alone. These are most commonly the small invasive cancers, which are of the greatest prognostic significance in breast cancer screening.     

Batch Reading and Interrupted Interpretation of Digital Screening Mammograms Without and With Tomosynthesis

ObjectiveTo compare batch reading and interrupted interpretation for modern screening mammography.MethodsWe retrospectively reviewed digital mammograms without and with tomosynthesis that were originally interpreted with batch reading or interrupted interpretation between January 2015 and June 2017. The following performance metrics were compared: recall rate (per 100 examinations), cancer detection rate (per 1,000 examinations), and positive predictive values for recall and biopsy.ResultsIn all, 9,832 digital mammograms were batch read, yielding a recall rate of 9.98%, cancer detection rate of 4.27, and positive predictive values for recall and biopsy of 4.40% and 35.5%, respectively. There were 49,496 digital mammograms that were read with interrupted interpretation, yielding a recall rate of 11.3%, cancer detection rate of 4.44, and positive predictive values for recall and biopsy of 3.92% and 30.1%, respectively. Of the digital mammograms with tomosynthesis, 7,075 were batch read, yielding a recall rate of 6.98%, cancer detection rate of 5.37, and positive predictive values for recall and biopsy of 7.69% and 38.0%, respectively. Of the digital mammograms with tomosynthesis, 24,380 were read with interrupted interpretation, yielding a recall rate of 8.30%, cancer detection rate of 5.41, and positive predictive values for recall and biopsy of 6.52% and 33.3%, respectively. For both digital mammograms without and with tomosynthesis, recall rates improved with batch reading compared with interrupted interpretation (P < .001), but no significant differences were seen for other metrics.DiscussionBatch reading digital mammograms without and with tomosynthesis improves recall rates while maintaining cancer detection rates and positive predictive values compared with interrupted interpretation.     

Radiation doses received in the UK Breast Screening Programme in 2001 and 2002

The mean glandular doses (MGD) to samples of women attending for mammographic screening are measured routinely at screening centres in the UK Breast Screening Programme (NHSBSP). This paper reviews a large representative sample of dose measurements collected during screening in the NHSBSP in 2001 and 2002 for 53 218 films, using 290 X-ray sets, for 16 505 women. The average MGD was 2.23 mGy per oblique film and 1.96 mGy per craniocaudal film; similar to those found previously in the NHSBSP for the years 1997 and 1998. Increasing use of sophisticated units with automatic beam quality selection has reduced the radiation dose received by large breasts, with only 2% of oblique mammograms having doses in excess of 5 mGy. The increasing use of large format film has also reduced the doses to this sub-group. However the total dose per woman has increased due to the introduction of two view screening at every visit. The MGD to the standard breast was found to vary from 0.76 mGy to 2.29 mGy, with 97% of units below the recommended upper limit of 2 mGy, illustrating the benefit of strict quality control. A reduction in dose of 3% was observed between the age bands 50-54 years and 60-64 years. This study has confirmed that the proposed national diagnostic reference level (NDRL) of 3.5 mGy for 55 mm thick breasts is an appropriate value to identify systems giving unusually high doses, with just 3.5% of systems exceeding this level. In most cases these higher doses were explained by the design of one particular make of X-ray set and its mode of operation. Average doses for oblique views of average sized breasts were fairly well correlated with the dose to the standard breast, and typically 42% higher. This highlights the need for a revised definition of the standard breast used in the UK to better reflect the exposure factors and doses received in clinical practice.     

Initial experiences of using an automated volumetric measure of breast density: the standard mammogram form

Limitations of area based measures of breast density have led several research groups to develop volumetric measures of breast density, for use in predicting risk and in epidemiological research. In this paper, we describe our initial experiences using an automated algorithm (standard mammogram form, SMF) to estimate the volume of the breast that is dense from digitized film mammograms. We performed analyses on 3816 mammograms of 626 women, who were part of the Glasgow Alumni Cohort and had mammograms taken within the Scottish Breast Screening Programme between 1989 and 2002. Absolute volume of dense breast tissue (SMF volume) and the percentage of the volume of the breast that is dense (SMF%) were calculated. The median (interquartile range) of SMF volume was 66 cm3 (48 to 98), and of SMF% was 23.4% (18.6 to 29.7). SMF%, but not SMF volume, was positively related to a six category classification (SCC) of visually assigned area-based breast density (increase in ln(SMF%) per category increase in SCC: 0.04% (95% CI: 0.03-0.05). The SMF algorithm produced lower SMF volume for craniocaudal (CC) compared with mediolateral oblique (MLO) views, but CC/MLO differences for SMF% were small. The mean right/left difference for ln(SMF volume) was -0.027 cm3 (95% confidence interval (CI) -0.044 to -0.009) and of ln(SMF%) was 0.005% (95% CI -0.008% to 0.019%). We present these initial data as a background for future analytical work using SMF.     

An evaluation of the use of pectoral muscle to nipple level as a component to assess the quality of the medio-lateral oblique mammogram

Objective: The national breast screening quality assurance (QA) guidelines state that medio-lateral oblique mammograms (MLO) should achieve the pectoral muscle to nipple level in 75% of cases using a line parallel to the horizontal edge of the film (PL). An alternative method would be to use a line at 90 degrees to the tangent of the breast at the point of the nipple (TM). The aim of this study was to evaluate these methods.Method: Questionnaires were sent to all breast screening units requesting that 50 randomly selected technically adequate MLOs be evaluated using the PL and TM.Results: From 54 replies (52%) the mean percentage for the PL was 40.5% (range 19–89). Only one unit achieved the QA objective. The mean percentage for the TM was 93% (range 83–100). P<0.001.Conclusion: The PL method for assessing the pectoral muscle to nipple level is reproducible but cannot be achieved in the majority of cases. The QA guidelines' target would be achievable if the TM was used to assess the pectoral muscle to nipple level. However some doubts have been raised as to the reproducibility of this method. As all the mammograms were deemed technically adequate the indication is that the QA guidelines are unachievable rather than there being a short fall in the quality of the mammograms.     

全视野数字乳腺摄影结合乳腺数字体层合成摄影的辐射剂量与压迫厚度及乳房密度的相关性研究

目的 对比分析乳腺数字体层摄影及全数字乳腺摄影（DBT/FFDM）模式平均腺体剂量（AGD）与乳房密度、压迫厚度的关系,探讨不同类型（厚度和密度）乳房在具体情况下摄影方式的优化选择与应用。方法 回顾性分析229例乳房Combo （DBT+FFDM）临床资料,分别收集记录双乳正位（CC）及内外斜位（MLO）压迫厚度、AGD、kVp和乳房量化密度（Q_abd）类型,分析DBT/FFDM模式下压迫厚度、密度与AGD之间的关系。结果 DBT/FFDM模式AGD与压迫厚度（CC位：r=0.55、0.53,P<0.001;MLO位：r=0.62、0.48,P<0.001）、乳房密度（CC位：r=0.36、0.39,P<0.001;MLO位：r=0.16、0.30,P<0.001）正相关;DBT模式AGD组间差异小,FFDM模式AGD组间差异大（厚度分组CC位：F=35.29、31.32,P<0.005;MLO位：F=44.83、27.02,P<0.005;Q_abd分类CC位：F=18.68、19.76,P<0.005;MLO位：F=4.58、10.52,P<0.005）;Q_abd分类高的乳房平均压迫厚度较低（CC位：F=16.28,P<0.005;MLO位：F=17.81,P<0.005）;同时考虑压迫厚度与乳房密度交互作用影响,仅在MLO位DM模式对AGD有交互作用（F=3.16,P=0.005）。结论 DBT/FFDM两种模式剂量累积可能增加辐射风险;乳腺摄影优先采用单视图CC/MLO-DBT或CC/MLO-（DBT+FFDM）+单视图MLO/CC-FFDM模式,在减低辐射剂量风险方面有积极作用。