Mammography Dose Survey Using International Quality Standards

Digital mammography is the current standard for breast cancer screening. The absence of any dosimetric data, the quality standards, and the fear of radiation detriment, sometimes, hampers the smooth introduction of this technology and the launch of breast cancer screening programmes. As the breast cancer screening programmes are in development in Morocco, quality standards have been set in this study, so that any new breast cancer screening service could get started with their first analysis. The purpose of this study was to report the first Moroccan breast dose and to test quality standards compared with European guidelines. A dosimetric study is conducted by calculating mean glandular dose (MGD) for patients' breasts and polymethyl methacrylate (PMMA) for each thickness from recorded radiographic factors and X-ray tube (output and half-value layer) measurements using Dance's model for a digital mammography system. This is carried out to determine the correlation between phantom and patient measurements.The mean MGD for patient data was 1.02 ± 0.5 mGy and the compressed breast thickness was 55 ± 14 mm. For compressed breast thickness range of 50–60 mm, the MGD was 0.94 ± 0.3 mGy and the dose calculated with PMMA phantom for the same range thickness was 1.33 mGy. The results of MGD as a function of PMMA thickness is lower than the achievable limit curve proposed in the European guidelines. The average doses, which depend on the technical parameters of the mammography equipment, are in line with values obtained in European guidelines. In addition, an investigation is needed throughout the Moroccan territory, in the sense of optimization of radiological practices and techniques in mammographic centres aligning with the international recommendations.     

Radiation dose from digital breast tomosynthesis screening – A comparison with full field digital mammography

ObjectivesTo compare Mean Glandular Dose (MGD) and effective dose from digital breast tomosynthesis (DBT) screening with that from full field digital mammography (FFDM) screening.MethodTo simulate compressed breasts, two Perspex-polyethylene breast phantoms were used, one phantom for compressed breast in craniocaudal and the other for compressed breast in mediolateral oblique. An adult ATOM dosimetry phantom was loaded with high sensitivity thermoluminescence dosimeters; the phantom was then positioned on Hologic Selenia Dimensions mammographic machine to imitate DBT and 4-view FFDM screening. Organ radiation doses were measured from 4-view DBT and 4-view FFDM (craniocaudal and mediolateral oblique views for each breast). Organ radiation doses were used to calculate effective dose from one screening session.ResultsMGD for DBT was 3.6 mGy; MGD for FFDM was 2.8 mGy. For DBT, other organs (e.g. thymus, lungs, salivary glands, thyroid, contralateral breast and bone marrow) radiation dose was also higher than for FFDM. The use of DBT for breast cancer screening increases the effective dose (E) of one screening session by 22%. E for DBT was 0.44 mSv; E for FFDM was 0.34 mSv.ConclusionThe use of DBT for breast cancer screening increases the radiation dose to screening clients.     

对比增强乳腺X线摄影与全视野乳腺X线摄影辐射剂量

目的 观察对比增强乳腺X线摄影（CEM）与全视野乳腺X线摄影（FFDM）乳腺辐射剂量及其与腺体压迫厚度的相关性。方法 采用模体实验对比同机FFDM及CEM 2种模式下平均腺体剂量（AGD）。102例乳腺疾病患者接受CEM（CEM组），另104例接受同机FFDM（FFDM组），记录2组AGD及腺体压迫厚度；按美国放射学院（ACR）第5版乳腺影像报告数据系统（BI-RADS）标准区分致密腺体及非致密腺体，比较组间及不同类型腺体间AGD和腺体压迫厚度差异，分析AGD与腺体压迫厚度的相关性。结果 模体实验结果显示低能CEM与FFDM的AGD相仿。CEM组非致密腺体22例，致密腺体80例；FFDM组非致密腺体39例，致密腺体65例；2组腺体压迫厚度差异无统计学意义（U=4 823.50，P>0.05）。CEM组总AGD与FFDM组差异无统计学意义（U=5 249.50，P>0.05），低能CEM的AGD低于FFDM组（U=2 111.00，P<0.05）。FFDM组AGD（r=0.45）及CEM组总AGD（r=0.79）与腺体压迫厚度均呈正相关（P均<0.05）。对非致密腺体，CEM组AGD高于FFDM组（U=266.00，P<0.05），而对致密腺体，CEM组AGD与FFDM组AGD差异无统计学意义（U=2 223.00，P>0.05）。FFDM组致密腺体AGD高于非致密腺体（U=846.50，P<0.05），而CEM组致密腺体与非致密腺体AGD差异无统计学意义（U=690.50，P>0.05）。结论 CEM总辐射剂量与FFDM相仿；压迫后腺体厚度越薄，辐射剂量越低；CEM对致密型腺体更具优势。     

Dosimetric and Contrast Noise Ratio Comparison of Three Different Digital Imaging Technologies in Mammography

PurposeThe purpose of the study was to compare the three most common technologies available in digital mammography based in the evaluation of average glandular dose and contrast noise ratio (CNR).MethodThe average glandular dose was estimated with a direct digital detector (aSe) with a pixel size of 0.85 μm, a photon counter with a pixel size of 50 μm and a computerized radiography (CR) system. A semiconductor detector was used to measure the input kerma to the detector, and the average glandular dose was calculated from the conversion factors dependent on the anode filter combination, half value layer and breast glandularity.ResultsThe average glandular dose obtained with polymethyl methacrylate and CNR of mean thickness 4.5 cm using direct digital equipment was 1.02 mGy and CNR = 7.4; using the photon counter it was 0.43 mGy and CNR = 4.7 in C100 mode, and 0.64 mGy and CNR = 5.7 in C120 mode; and using the photostimulable CR, the estimated value was 1.65 mGy and CNR = 5.1.ConclusionsThe photon counter offers a lower average glandular dose than the other two devices with adequate image quality (CNR). The CR equipment offers a similar CNR value but delivers a higher dose than the new generations of available mammograms.     

几何模型匹配乳腺头足位与内外斜位X线片所示病灶

目的 观察几何模型(GM)匹配乳腺头足(CC)位与内外斜(MLO)位X线片所示病灶的价值。方法 回顾性分析493例接受乳腺CC位和MLO位X线摄影的乳腺病灶患者,共598个乳腺病灶,包括499个钙化灶和99个肿块。构建GM用于匹配CC与MLO位片所示乳腺病灶,再以环形法(AB)和直线法(SS)进行对比,分别计算匹配误差,包括GM匹配误差、AB径向误差及SS轴向误差;分析GM对CC及MLO位图像中同一病灶的匹配性能,评价其应用价值。结果 GM对乳腺钙化灶和肿块的匹配误差分别为2.85(1.45,5.08)及3.70(1.35,6.25)mm,差异无统计学意义(Z=-1.344,P=0.179)。对乳腺上部病灶,AB匹配的径向误差和SS匹配的轴向误差均大于下部病灶(P均<0.001);对乳腺外侧病灶,AB的径向误差和SS的轴向误差均大于内侧病灶(P均<0.05)。GM、AB及SS间匹配误差整体差异有统计学意义(H=93.012,P<0.001);两两比较差异均有统计学意义(P均<0.05),GM匹配性能明显优于AB和SS。GM匹配误差与摄片时乳腺压迫厚度无明显相关性...     

Local Diagnostic Reference Levels in Interventional Radiology

PurposeInterventional cardiology procedures, during which live images are acquired, involve exposure to x-rays. The use of fluoroscopy can cause high radiation doses to patients and operators because of the prolonged duration of x-ray emission. For this reason, special attention and constant vigilance represent challenges for commissions and groups of experts in the field. The purpose of this study is to establish local diagnostic reference levels (DRLs) for these procedures, to improve radiological practice, and to optimize radiation doses.MethodsThis work was carried out in two university hospitals and two private medical facilities in Rabat, the capital of Morocco, during the period 2017–2018. The study concerns 657 interventional cardiology procedures (457 coronary angiography [CA] and 200 percutaneous transluminal coronary angioplasty [PTCA]), performed by 11 cardiologists on different installations in 5 catheterization rooms. The data collected for each procedure were patient age, height and weight, dosimeter indicators in terms of dose area product (P_KA), total air kerma at the reference point (K_ar), fluoroscopy time (FT), and the number of frames, together with the primary beam parameters as kV and total mAs. The proposed DRLs were set from the 75th percentile of the P_KA and FT.ResultsThe mean of P_KA for CA and PTCA procedures were 29.2 Gy1cm² and 70.4 Gy1cm², respectively, the mean of fluoroscopy time were 4.0 min and 12.17 min for 334 and 685 frames, respectively. Results for the local DRLs were 37.3 and 87.1 Gy cm² for P_KA and 4.48 and 16.15 min for FT, corresponding to CA and PTCA procedures.ConclusionThis work focuses on proposing local DRLs in Morocco for CA and PTCA procedures. The results show that the values found conform with those of international studies.     

全数字乳腺X线摄影规范化操作探讨

目的通过回顾性分析全数字化乳腺X线摄影图像,探讨全数字化乳腺X线摄影技术规范化操作的重要性。方法采用全数字化钼铑双靶X线乳腺摄影机,对548例女性受检者进行乳腺轴位(CC位)和内外斜位(MLO位)投照检查,共获得2 160幅图像,依据评片标准对每幅图像进行评价并总结其投照技术要点。结果 2 160幅乳腺图像中,Ⅰ级片2 127幅(98.5%),Ⅱ级片26幅(1.2%),Ⅲ级片7幅(0.3%)。Ⅱ和Ⅲ级片中CC位19幅,MLO位14幅。造成Ⅱ和Ⅲ级片的原因主要有:CC位包括肩部软组织遮挡13幅(13/19),未显示乳房内侧缘7幅(7/19),皮肤皱褶2幅(2/19)和乳头偏离照片中心横轴线1幅(1/19)。MLO位腋下组织包括较少8幅(8/14),皮肤皱褶4幅(4/14)、乳头下垂或不呈侧位3幅(3/14)和胸大肌位置不正确2幅(2/14)。共26幅图像进行了相应体位的重新摄影。结论全数字化乳腺X线摄影过程中规范的投照体位和正确实施乳房压迫,可有效避免Ⅱ级或Ⅲ级片,减少检查次数。     

相同平均腺体剂量下PCM系统与SFM系统和CR系统乳腺摄影的影像比较

目的 研究PCM系统、SFM系统和普通CR系统乳腺摄影在相同平均腺体剂量条件下影像质量的差异.方法 使用TORMAX和CDMAM模体,在SFM系统进行曝光,以相同AGD下的曝光组合在PCM及CR系统上进行相应模体摄影,对所得图像分别进行评分和统计学分析,比较在相同AGD下三种乳腺X线摄影系统成像质量的差异.结果 在相同AGD下,PCM在低对比分辨率方面与SFM系统、CR系统相比有明显优势;在检出微小钙化方面,PCM几乎可以达到SFM系统水平,但在高对比分辨率方面不及SFM系统.结论 PCM系统综合的影像质量优于SFM和CR系统.     

Patient radiation dose during diagnostic and interventional cardiology procedures: A study in a tertiary hospital

BackgroundFluoroscopy-guided diagnostic and interventional cardiology (IC) procedures help to identify and treat several problems associated with the heart. However, these procedures expose patients, cardiologists, radiographers, and nurses to radiation doses. Due to the risk that ionizing radiation poses, concerns have been raised and studies are continually being done to ensure that optimization is achieved during such procedures. This study assessed patient radiation dose during diagnostic and interventional cardiology procedures as well as right heart studies at a tertiary hospital in Ghana to formulate the facility's diagnostic reference levels (DRLs) for optimization purposes. As this study was the first of its kind in Ghana, it was a vital step towards dose optimization within the local department, as well as contributing to future DRLs in Ghana.MethodsThe study collected dose (air kerma, and kerma area product (KAP) and procedural data, and assessed any correlation between parameters such as fluoroscopy time and KAP, and between body mass index (BMI) and KAP. The DRL values were determined as the 75th percentile level for the dose distribution for the various IC procedures including percutaneous coronary interventions (PCI), coronary angiography (CA), and right heart catheterization (RHC). Data were analyzed using SPSS version 23.ResultsCA was the most frequently performed IC procedure (77.3%), while RHC was the least recorded (3.3%). The highest mean KAP was observed during the PCI procedure. The proposed diagnostic reference levels (DRLs) were 162.0 Gy.cm² (PCI), 69.4 Gy.cm² (CA), 39.8 Gy.cm² (RHC) and 159.9 Gy.cm² (CA+PCI). Patients who presented for the CA+PCI and RHC procedures received the highest and lowest mean KAP of 159.9 Gy.cm² and 39.8 Gy.cm² of radiation respectively.ConclusionThis study, therefore, concludes that there is a need for dose optimization of radiation exposures for IC procedures at the cardiothoracic center in Ghana.     

PCM乳腺摄影系统与CR系统临床应用的初步比较

目的 探讨相位对比乳腺X线摄影系统(PCM)与CR系统在乳腺实体成像质量上的差异.方法 24例患者,患侧乳腺在PCM系统或CR系统(随机选择)进行轴位(CC)或侧斜位(MLO)投照,在另一系统进行另一体位投照.30名正常体检者,一侧乳腺在PCM系统或CR系统上(随机选择)进行CC及MLO投照,另一侧乳腺在另一系统进行两个体位的投照.对所得影像进行解剖及病变细节显示情况的评分,分析PCM与CR系统对于乳腺实体摄影成像质量的差异.结果 病变组:PCM系统在肿块边缘清晰度、内部结构显示及钙化边缘清晰度方面均明显优于CR系统(P=0.0003);正常体检组:正常乳腺双侧对照:PCM系统在锐利度、对比度和噪声方面均明显优于CR系统(P<0.05).结论 PCM系统与CR系统在乳腺实体成像质量上存在显著差异,PCM系统的图像基本质量及对病变细节的显示情况明显优于CR系统.     

Deformable mapping using biomechanical models to relate corresponding lesions in digital breast tomosynthesis and automated breast ultrasound images

This work investigates the application of a deformable localization/mapping method to register lesions between the digital breast tomosynthesis (DBT) craniocaudal (CC) and mediolateral oblique (MLO) views and automated breast ultrasound (ABUS) images. This method was initially validated using compressible breast phantoms. This methodology was applied to 7 patient data sets containing 9 lesions. The automated deformable mapping algorithm uses finite element modeling and analysis to determine corresponding lesions based on the distance between their centers of mass (d_COM) in the deformed DBT model and the reference ABUS model. This technique shows that location information based on external fiducial markers is helpful in the improvement of registration results. However, use of external markers are not required for deformable registration results described by this methodology. For DBT (CC view) mapped to ABUS, the mean d_COM was 14.9 ± 6.8 mm based on 9 lesions using 6 markers in deformable analysis. For DBT (MLO view) mapped to ABUS, the mean d_COM was 13.7 ± 6.8 mm based on 8 lesions using 6 markers in analysis. Both DBT views registered to ABUS lesions showed statistically significant improvements (p ≤ 0.05) in registration using the deformable technique in comparison to a rigid registration. Application of this methodology could help improve a radiologist's characterization and accuracy in relating corresponding lesions between DBT and ABUS image datasets, especially for cases of high breast densities and multiple masses.     

Comparative outcomes of Inferior Vena Cava filters placed at bedside using digital radiography versus conventional fluoroscopy

PurposeTo retrospectively assess the outcomes of Inferior Vena Cava (IVC) filters placed in critically ill patients in the ICU at bedside using digital radiograph (DR) guidance with previous cross-sectional imaging for planning, compared to IVC filters placed by conventional fluoroscopy (CF).Method and materialsThe cohort consisted of 129 IVC filter placements; 48 placed at bedside and 81 placed conventionally from July 2015 to September 2016. Patient demographics, indication, radiation exposures, access site, procedural duration, dwell time, and complications were identified by the EMR. IVC Filter positioning with measurements of tip to renal vein distance and lateral filter tilt were performed when cavograms or post placement CTs were available for review. Statistical analysis was performed using Stata IC 11.2.ResultsTechnical success of the procedure was 100% in both groups. Procedural duration was longer at the bedside lasting 14.5 +/- 10.2 versus 6.7 +/- 6.0 ​min (p<0.0001). The bedside DR group had a median radiation exposure of 25 ​mGy (15–35) and the CF group had mean radiation exposure of 256.94 ​mGy +/- 158.6. There was no significant difference in distance of IVC tip to renal vein (p=0.31), mispositioning (p=0.59), degree of filter tilt (p=0.33), or rate of complications (p=0.65) between the two groups.ConclusionIVCF placement at the bedside using DR is comparable to CF with no statistical difference in outcomes based on IVCF positioning, degree of lateral tilt or removal issues. It decreased radiation dose, but with overall increased procedural time.     

Development and Evaluation of a CT Pulmonary Angiography Protocol Dedicated to Pregnant and Postpartum Women

IntroductionThis study presents and evaluates a CT pulmonary angiography protocol dedicated to pregnant women. The specific feature of this protocol is to place the region of interest (ROI) (bolus detection) in the superior vena cava. The objective is to evaluate the performances of this method.Materials and methodsThe protocol uses a iodine-based contrast agent at 300mgI/mL and an injection rate of 5 to 6 mL/sec for an injection volume of 50 mL of iodine contrast agent followed by 40 mL of NaCl. The ROI is positioned on the superior vena cava, with a 100 Hounsfield units (HU) threshold, and the acquisition is performed at 100 kVp. This protocol was evaluated retrospectively on a large population (n = 105: group 1) and compared with a control group that did not benefit from this protocol (n = 55: group 2). Both groups were studied on the same device in the same center. Each examination was evaluated and classified into 3 groups: optimal, suboptimal, and noncontributory. Dose length products (DLP) values were also recorded. Statistical tests were applied to the data collected.ResultsThe rate of noncontributory examinations increased from 43.1% for the control group to 4.8% for the new protocol group. The reference enhancement level in the pulmonary trunk is 250 UH. The mean enhancement in the pulmonary trunk of the new protocol group (332 HU (±71 HU (±71 HU)) is significantly greater than the reference value of 250 HU (P < .0001), which is not the case for control group (P = .3485 > .05), which has a mean enhancement of 239 HU (±87 HU). The control group had a mean DLP of 225 mGy.cm (±81 mGy.cm), and the new-protocol group had a mean DLP of 189 mGy.cm (±75 mGy.cm).DiscussionOur noncontributory examination rate is the lowest rate described in the literature. Our protocol contradicts standard practices of placing an ROI in the pulmonary trunk for bolus detection of iodinated contrast media.ConclusionThe results of this study showed that this protocol reduces the number of noncontributory examinations while reducing the dose delivered to patients. This robust protocol is applicable to other devices and meets perfectly radiation-safety requirements and injected contrast media volume limitation.     

Deformable Mapping Method to Relate Lesions in Dedicated Breast CT Images to Those in Automated Breast Ultrasound and Digital Breast Tomosynthesis Images

This work demonstrates the potential for using a deformable mapping method to register lesions between dedicated breast computed tomography (bCT) and both automated breast ultrasound (ABUS) and digital breast tomosynthesis (DBT) images (craniocaudal [CC] and mediolateral oblique [MLO] views). Two multi-modality breast phantoms with external fiducial markers attached were imaged by the three modalities. The DBT MLO view was excluded for the second phantom. The automated deformable mapping algorithm uses biomechanical modeling to determine corresponding lesions based on distances between their centers of mass (d_COM) in the deformed bCT model and the reference model (DBT or ABUS). For bCT to ABUS, the mean d_COM was 5.2 ± 2.6 mm. For bCT to DBT (CC), the mean d_COM was 5.1 ± 2.4 mm. For bCT to DBT (MLO), the mean d_COM was 4.7 ± 2.5 mm. This application could help improve a radiologist's efficiency and accuracy in breast lesion characterization, using multiple imaging modalities.     

Preclinical Evaluation and Dosimetry of [111In]CHX-DTPA-scFv78-Fc Targeting Endosialin/Tumor Endothelial Marker 1 (TEM1)

Purpose

Endosialin/tumor endothelial marker-1 (TEM1) is an attractive theranostic target expressed by the microenvironment of a wide range of tumors, as well as by sarcoma and neuroblastoma cells. We report on the radiolabeling and preclinical evaluation of the scFv78-Fc, a fully human TEM1-targeting antibody fragment cross-reactive with mouse TEM1.

Procedures

The scFv78-Fc was conjugated with the chelator p-SCN-Bn-CHX-A”-DTPA, followed by labeling with indium-111. The number of chelators per molecule was estimated by mass spectrometry. A conventional saturation assay, extrapolated to infinite antigen concentration, was used to determine the immunoreactive fraction of the radioimmunoconjugate. The radiopharmaceutical biodistribution was assessed in immunodeficient mice grafted with Ewing’s sarcoma RD-ES and neuroblastoma SK-N-AS human TEM1-positive tumors. The full biodistribution studies were preceded by a dose-escalation experiment based on the simultaneous administration of the radiopharmaceutical with increasing amounts of unlabeled scFv78-Fc. Radiation dosimetry extrapolations to human adults were obtained from mouse biodistribution data according to established methodologies and additional assumptions concerning the impact of the tumor antigenic sink in the cross-species translation.

Results

[¹¹¹In]CHX-DTPA-scFv78-Fc was obtained with a radiochemical purity >?98 % after 1 h incubation at 42 °C and ultrafiltration. It showed good stability in human serum and >?70 % immunoreactive fraction. Biodistribution data acquired in tumor-bearing mice confirmed fast blood clearance and specific tumor targeting in both xenograft models. The radiopharmaceutical off-target uptake was predominantly abdominal. After a theoretical injection of [¹¹¹In]CHX-DTPA-scFv78-Fc to the reference person, the organs receiving the highest absorbed dose would be the spleen (0.876 mGy/MBq), the liver (0.570 mGy/MBq) and the kidneys (0.298 mGy/MBq). The total body dose and the effective dose would be 0.058 mGy/MBq and 0.116 mSv/MBq, respectively.

Conclusions

[¹¹¹In]CHX-DTPA-scFv78-Fc binds specifically to endosialin/TEM1 in vitro and in vivo. Dosimetry estimates are in the range of other monoclonal antibodies radiolabeled with indium-111. [¹¹¹In]CHX-DTPA-scFv78-Fc could be potentially translated into clinic.

     

Improvement in chest compression quality using a feedback device (CPRmeter): a simulation randomized crossover study

PurposesCardiac arrest survival depends on celerity and efficiency of life support action. Guidelines emphasized the chest compression (CC) quality and feedback devices are encouraged. The purpose is to study the impact of the CPRmeter feedback device on resuscitation performed by untrained rescuers.Basic proceduresThis is a prospective randomized crossover study on manikins (Resusci Anne). One hundred and forty four students inexperienced in cardiopulmonary resuscitation representing untrained rescuers were included. Participants performed 2 minutes of CC without interruption with (group G) or without (group B) feedback. Four months passed between the 2 crossover phases to avoid resilience effect. Data collected by the CPRmeter device were: CC rate, depth and release.Main findingsEfficient CC rate ([simultaneous and correct CC rate, depth and release] primary outcome) (absolute difference [95% CI]) was significantly improved in group G (71%) compared to group B (26%; [45 {36-55}]; P < .0001). Adequate depth rate (> 38 mm) was significantly improved in group G (85%) compared to group B (43%; [42 {33-52}]; P < .0001). Adequate CC rate (90-120/min) was significantly improved in group G (81%) compared to group B (56%; [25 {15-35}]; P < .0001). The average CC rate and depth in group G were significantly less dispersed around the mean compared to group B (test of variance P < .007; P < .015 respectively).Principal conclusionsThe use of the CPRmeter significantly improved CC quality performed by students inexperienced in cardiopulmonary resuscitation.     

基于多中心数字化乳腺X线摄影影像组学预测乳腺癌人表皮生长因子受体-2过表达

目的 观察基于多中心数字化乳腺X线摄影(DM)影像组学预测乳腺癌人表皮生长因子受体-2(HER-2)过表达的价值。方法 回顾性分析来自机构1(n=336)、2(n=142)、3(n=130)共608例经病理证实乳腺癌患者的DM资料。按照7∶3比例将来自机构1、2共478例分为训练集(334例，其中92例HER-2阳性、242例HER-2阴性)和验证集(144例，40例HER-2阳性、104例HER-2阴性);以来自机构3的130例(33例HER-2阳性及97例HER-2阴性)为外部验证集。于显示病变面积较大的内外斜(MLO)位或头足(CC)位DM图像中勾画病灶ROI,提取及筛选最佳影像组学特征，以支持向量机(SVM)构建影像组学模型，用于预测乳腺癌HER-2过表达；采用受试者工作特征(ROC)曲线评估模型的诊断效能，绘制校准曲线及决策曲线，评价其校准度及临床获益。结果 共筛选出3个最佳影像组学特征，以之构建的SVM影像组学模型预测训练集、验证集及外部验证集乳腺癌HER-2过表达的曲线下面积(AUC)分别为0.824、0.775及0.812。校准曲线显示，该模型在训练集、验证集及外部验证...     

基于深度学习的乳腺X线摄影钙化检测系统对乳腺可疑钙化的检出效能

目的 评价基于深度学习（DL）的乳腺X线摄影钙化检测系统对乳腺可疑钙化的检出效能。方法 回顾分析932例接受乳腺X线检查患者的头足位（CC）和内外斜位（MLO）资料,由2名低年资医师和DL系统盲法独立阅片,一名高年资医师审核结果。比较DL系统与低年资医师检出敏感度差异,结合双向表χ²检验,评价不同BI-RADS分类、钙化形态和分布影响。结果 针对3 728幅影像（932例）,标记可疑钙化274例。2名低年资医师和DL系统的检出敏感度分别是76.64%（210/274）、82.12%（225/274）和99.64%（273/274）。DL系统检出敏感度不受钙化形态、分布、BI-RADS分类等因素的影响（P均>0.05）,而低年资医师对无定形钙化和团簇分布钙化的敏感度明显降低（P均<0.05）。结论 基于DL的乳腺X线影像钙化检出系统检出对可疑形态钙化的敏感度高且稳定,可辅助临床医师减少漏检。