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21.
22.
目的 比较超声(US)和钼靶X线乳腺摄影(MTM)评估不同类型乳腺微小肿块的价值。方法 选取562例经手术或穿刺确诊,并具有完整US、MTM以及病理结果的乳腺微小肿块患者,根据MTM图像将乳腺分为4种类型,比较US和MTM对不同类型乳腺微小肿块的检出率、敏感度、特异度及准确率,并分析US与MTM的诊断一致性。结果 在美国放射学院(ACR)a类乳腺,MTM对微小肿块的检出率以及诊断恶性微小肿块的敏感度、准确率均高于US(P均<0.05),US和MTM的诊断一致性一般(Kappa=0.47);在ACR b类和ACR c类乳腺,MTM和US对微小肿块的检出率以及诊断恶性微小肿块的敏感度、特异度以及准确率差异无统计学意义(P均>0.05),两者的诊断一致性较好(Kappa=0.78、0.76);在ACR d类乳腺,US对微小肿块的检出率以及诊断恶性微小肿块的敏感度、准确率均高于MTM(P<0.05),两者的诊断一致性较差(Kappa=0.35)。结论 对于ACR a类乳腺发生的微小肿块,MTM优于US;对于ACR b类和ACR c类乳腺微小肿块,US和MTM无明显差异;对于ACR d类乳腺微小肿块,US优于MTM。  相似文献   
23.
Breast density is a strong risk factor for breast cancer. In this paper, we present an automated approach for breast density segmentation in mammographic images based on a supervised pixel-based classification and using textural and morphological features. The objective of the paper is not only to show the feasibility of an automatic algorithm for breast density segmentation but also to prove its potential application to the study of breast density evolution in longitudinal studies. The database used here contains three complete screening examinations, acquired 2 years apart, of 130 different patients. The approach was validated by comparing manual expert annotations with automatically obtained estimations. Transversal analysis of the breast density analysis of craniocaudal (CC) and mediolateral oblique (MLO) views of both breasts acquired in the same study showed a correlation coefficient of ρ = 0.96 between the mammographic density percentage for left and right breasts, whereas a comparison of both mammographic views showed a correlation of ρ = 0.95. A longitudinal study of breast density confirmed the trend that dense tissue percentage decreases over time, although we noticed that the decrease in the ratio depends on the initial amount of breast density.  相似文献   
24.
Breast cancer is becoming a leading death of women all over the world; clinical experiments demonstrate that early detection and accurate diagnosis can increase the potential of treatment. In order to improve the breast cancer diagnosis precision, this paper presents a novel automated segmentation and classification method for mammograms. We conduct the experiment on both DDSM database and MIAS database, firstly extract the region of interests (ROIs) with chain codes and using the rough set (RS) method to enhance the ROIs, secondly segment the mass region from the location ROIs with an improved vector field convolution (VFC) snake and following extract features from the mass region and its surroundings, and then establish features database with 32 dimensions; finally, these features are used as input to several classification techniques. In our work, the random forest is used and compared with support vector machine (SVM), genetic algorithm support vector machine (GA-SVM), particle swarm optimization support vector machine (PSO-SVM), and decision tree. The effectiveness of our method is evaluated by a comprehensive and objective evaluation system; also, Matthew’s correlation coefficient (MCC) indicator is used. Among the state-of-the-art classifiers, our method achieves the best performance with best accuracy of 97.73 %, and the MCC value reaches 0.8668 and 0.8652 in unique DDSM database and both two databases, respectively. Experimental results prove that the proposed method outperforms the other methods; it could consider applying in CAD systems to assist the physicians for breast cancer diagnosis.  相似文献   
25.
目的:探讨乳腺X线摄影、彩色多普勒超声及二者联合诊断乳腺病变的价值。方法:回顾性分析经术后病理证实的153例女性乳腺肿块的超声及乳腺X线影像学资料,分析二者诊断乳腺病变的影像特点。结果:153例中良性63例,恶性90例。两种检查方法联合应用对乳腺恶性肿块诊断敏感性为97.8%,特异性90.5%,准确性为94.8%,高于单用一种检查方法(P<0.05)。结论:乳腺超声和乳腺X线在乳腺肿块诊断中联合应用可以提高乳腺病变的检出率及准确率,为临床提供诊断依据。  相似文献   
26.
目的对比分析乳腺导管原位癌伴微浸润(DCISM)与导管原位癌(DCIS)的X线及临床病理表现及DCISM的预测因子。方法收集2016年1月至2020年7月在青岛大学附属医院经手术病理证实的DCISM及DCIS患者626例,患者术前均接受乳腺X摄影检查。参照乳腺影像报告和数据系统(BI-RADS)标准对DCISM与DCIS患者X线表现进行分类诊断。采用χ2检验或Fisher确切概率法分析DCISM与DCIS患者临床病理及X线表现的差异性,应用单因素和多因素二元logistic回归分析探讨与DCISM相关的危险因素。结果626例患者中,DCISM患者171例,DCIS患者455例。单因素回归分析表明,肿瘤直径≥2.7cm、高核级别、粉刺性坏死、淋巴结阳性、Ki67高表达、雌激素受体及孕激素受体阴性是DCISM的预测因子(P<0.05)。多因素回归分析显示,肿瘤直径≥2.7cm(OR 2.229,95%CI 1.505~3.301,P<0.001)、高核级别(OR 1.711,95%CI 1.018~2.875,P=0.043)、淋巴结阳性(OR 4.140,95%CI 1.342~12.773,P=0.013)是DCISM的独立预测因子(P<0.05)。乳腺X线摄影中,DCIS与DCISM患者的病变类型、有无钙化及钙化分布差异具有统计学意义(χ2分别为17.42、9.65、9.10,P<0.05),17.6%(80/455)的DCIS患者表现为隐匿性病变,49.1%(84/171)的DCISM表现为钙化伴肿块、非对称致密、结构扭曲。团簇状钙化多见于DCIS(41.5%,120/289),而区域性钙化在DCISM中更普遍(35.9%,47/131)。结论乳腺X线摄影表现为钙化性病变及区域性钙化在DCISM中更常见。肿瘤直径≥2.7cm、高核级别、淋巴结阳性是DCISM的独立预测因子。  相似文献   
27.
ObjectivesThe aim of this paper is to illustrate the current status of imaging in high breast density as we enter a new decade of advancing medicine and technology to diagnose breast lesions.Key findingsEarly detection of breast cancer has become the chief focus of research from governments to individuals. However, with varying breast densities across the globe, the explosion of breast density information related to imaging, phenotypes, diet, computer aided diagnosis and artificial intelligence has witnessed a dramatic shift in new screening recommendations in mammography, physical examination, screening younger women and women with comorbid conditions, screening women at high risk, and new screening technologies. Breast density is well known to be a risk factor in patients with suspected/known breast neoplasia. Extensive research in the field of qualitative and quantitative analysis on different tissue characteristics of the breast has rapidly become the chief focus of breast imaging. A summary of the available guidelines and modalities of breast imaging, as well as new emerging techniques under study that can potentially provide an augmentation or even a replacement of those currently available.ConclusionDespite all the advances in technology and all the research directed towards breast cancer, detection of breast cancer in dense breasts remains a dilemma.Implications for practiceIt is of utmost importance to develop highly sensitive screening modalities for early detection of breast cancer.  相似文献   
28.
目的 探讨目测法及目测与半定量法结合分析乳腺专用伽玛显像(BSGI)图像对乳腺癌的诊断价值.方法 选取106例乳腺肿块拟行手术的患者,术前10 d内行BSGI,分别采用目测法(结果分为1~5级)和目测与半定量法结合分析图像.选出目测法分级≥3级的患者,选取其乳房头尾(CC)位与内外侧斜(MLO)位中病灶与邻近正常乳腺组织放射性计数比值(L/N)中的较大值作为BSGI图像分析的半定量指标.与术后病理进行对照,通过ROC曲线计算目测法诊断乳腺癌的灵敏度和特异性、目测与半定量法结合指标L/N的界值;两者结合采用序列试验方法计算其诊断乳腺癌的灵敏度和特异性.采用两样本t检验分析数据.结果 经手术及病理证实,106例乳腺肿块患者中良性疾病34例(49个良性病灶),乳腺癌72例(73个恶性病灶及4个良性病灶).目测法分级取3.5作为界值时,ROC AUC为0.901(95% CI:0.838~ 0.965)最大,此时BSGI诊断乳腺癌的灵敏度和特异性分别为94.4% (68/72)和73.5% (25/34).对目测法分级≥3级的85例进行半定量分析:取L/N 1.92作为界值,其ROC AUC为0.870(95% CI:0.756~ 0.984)最大;恶性组L/N为3.29± 1.30,明显高于良性组(2.02±0.65;t=5.63,P<0.05).目测与半定量法结合诊断乳腺癌的灵敏度和特异性分别为91.7% (66/72)和88.2% (30/34).结论 目测与半定量法结合分析BSGI图像,有助于提高乳腺癌诊断的特异性,具有增益价值.  相似文献   
29.
目的与非三阴性乳腺癌(non-TNBC)比较,探讨三阴性乳腺癌(TNBC)的乳腺X线特征。方法根据ER、PR、HER2表达情况,将737个乳腺癌肿块分成TNBC组(n=112)和non-TNBC组(n=625),回顾性分析两组患者的X线图像及临床病理资料。结果 TNBC肿瘤组织学分级高,腋窝淋巴结转移率高于non-TNBC组(P0.05)。在钼靶X线中,TNBC主要表现肿块(69.7%),很少表现为肿块伴钙化(16.5%)、局限性非对称致密(4.6%)、单纯钙化(2.8%)和结构扭曲(6.4%);肿块形状多为圆形(30.9%)或椭圆形(38.3%),很少表现为不规则形(11.7%);肿块边缘多为清晰边缘(30.9%),毛刺肿块少见(19.1%)。non-TNBC通常表现为肿块伴钙化(43.5%),钙化多见(58.8%);肿块形态主要为分叶形(40.4%)和不规则形(28.9%),毛刺征多见(43.6%)。结论 TNBC有其独特的影像表现,更倾向于良性肿瘤的特点,了解其X线特征有助于提高TNBC的诊断水平。  相似文献   
30.

Objective

This study investigated predictive factors of women's participation in organized mammography screening (OrgMS) and/or opportunistic mammography screening (OppMS) when the two screening modes coexist.

Methods

Questionnaires were sent to 6,000 women aged 51–74 years old invited to attend an OrgMS session between 2010 and 2011 in France. Data collected concerned the women's healthcare behaviour and their socioeconomic characteristics. Women without a personal or family history of breast cancer that could explain their participation in OppMS were retained in the generalized logits analysis.

Results

The data of 1,202 women were analysed. Of these, 555 (46.2%) had attended OrgMS only, 105 (8.7%) OppMS only and 542 (45.1%) had performed both OrgMS and OppMS. Multivariable analyses showed that women who had regular gynaecological check-ups were more likely to perform OppMS only or both OrgMS and OppMS, OR 95% CI were 2.1 [1.1–3.9], 1.9 [1.4–2.6], respectively. Being employed also increased participation in OppMS only [OR: 2.1 (1.2–3.7)] or both OrgMS and OppMS [OR: 1.5 (1.1–2.05)].

Conclusion and practice implications

In countries where OrgMS and OppMS coexist, strategies involving gynaecologists, referring doctors or company doctors and the organization of healthcare services to promote adequate screening round may help to reduce the overuse of mammography.  相似文献   
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