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81.
《Journal l'Association canadienne des radiologistes》2019,70(2):186-192
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. 相似文献
82.
仪器对凝血酶原时间国际标准化比值的影响及校正 总被引:11,自引:0,他引:11
为了评价血凝仪对国际标准化比值的影响。模拟WHO标定凝血质的参比方法,用一种已 知国际敏感指标的凝血质对两种血凝仪的特异性ISI进行标定,并以INR形式报告PT结果。 相似文献
83.
目的:探讨MRI横断面定量测定指标对髌骨关节不稳的诊断价值。方法回顾性分析髌骨关节不稳患者32例(髌骨关节不稳组)和正常人42例(对照组)的MRI影像学资料。两组均采取仰卧位及双膝完全伸直进行MRI检查,扫描范围均为右侧全膝关节。 MRI图像的测量指标包括股骨滑车面对称性、股骨滑车深度、股骨外侧滑车倾斜度、髌骨倾斜角、髌骨外移度、股骨滑车与胫骨结节间的水平距离( TTTG)。结果两组股骨滑车面对称性、股骨滑车深度、股骨外侧滑车倾斜度、髌骨倾斜角、髌骨外移度结果比较,差异有统计学意义(P<0.05),但是两组TTTG结果比较,差异无统计学意义(P>0.05)。股骨滑车面对称性、股骨滑车深度、股骨外侧滑车倾斜度、髌骨倾斜角、髌骨外移度和TTTG的ROC曲线下面积分别为0.954、0.955、0.943、0.922、0.971、0.521;股骨滑车面对称性、股骨滑车深度、股骨外侧滑车倾斜度、髌骨倾斜角、髌骨外移度诊断界值分别为54%、15°、5 mm、16°、3 mm,敏感度为91.3%、85.2%、91.5%、83.1%、79.1%,特异度分别为91.4%、97.5%、88.4%、90.1%、100%。结论在行膝关节伸直位MRI检查时,股骨滑车面对称性、股骨滑车深度、股骨外侧滑车倾斜度、髌骨倾斜角、髌骨外移度对髌骨关节不稳的诊断价值较高。 相似文献
84.
三种乳腺癌化疗方案的药物经济学分析 总被引:1,自引:1,他引:0
目的 从药物经济学角度评价乳腺癌术后3种化疗方案的经济学效果,为临床合理用药提供参考。方法 90例乳腺癌术后患者分为3组(TAC、PEC、AC),采用药物经济学的成本-效果分析法对3种化疗方案进行临床病例的回顾性分析比较(T:多西他赛,A:多柔比星,C:环磷酰胺,P:紫杉醇脂质体,E:表柔比星)。结果 3组化疗方案的总体有效率分别为71.87%,73.07%,65.62%;治疗成本分别为11713.49元,18197.79元和7795.82元;成本-效果比分别为162.98,249.04,118.80。化疗不良反应方面,PEC组发生率高于TAC组及AC组,差异有显著性(P≤0.05)。结论 TAC为乳腺癌术后化疗较佳的治疗方案,值得推广。 相似文献
85.
目的:探讨桡骨茎突狭窄性腱鞘炎(STRS)患者选用高频超声诊断的价值。方法:选2019年2月-2020年2月接收50例STRS患者研究,均实施高频超声检查,以手术结果为金标准,分析其检出率、准确率、灵敏性、特异性及血流动力学表现。结果:高频超声检出率96.00%,与金标准相比无差异,统计值P>0.05。高频超声准确率96.00%、灵敏性96.14%、特异性95.61%,与金标准相比无差异,统计值P>0.05。高频超声检查发现9例(18.00%)未见血流信号,41例(82.00%)见血流信号,其中1级25例(50.00%)、2级14例(28.00%)、3级2例(4.00%)。结论:高频超声诊断STRS准确率、灵敏度较高,且具有无创、快捷、低廉等优势,可为作为诊断STRS方案。 相似文献
86.
《Diagnostic and interventional imaging》2020,101(6):391-399
PurposeTo identify the optimal acquisition time to best discriminate between benign and malignant breast lesions on contrast-enhanced cone beam CT (CE-CBCT) and evaluate the potential of CE-CBCT to differentiate between breast cancer subtypes.Material and methodA total of 98 women with a mean age of 49 ± 10 (SD) years (range: 29–77 years) with 100 BI-RADS 4 or 5 breast lesions were prospectively included. CE-CBCT images were obtained at 1- and 2-min after intravenous administration of iodinated contrast material. Contrast enhancement of breast lesions on CE-CBCT were evaluated and compared between different subtypes. Cut-off values for best discriminating between benign and malignant breast lesions with CE-CBCT were obtained from receiver operating characteristic curves.ResultsMalignant breast lesions showed greater enhancement than benign ones at 1-min (67.28 ± 39.79 [SD] HU vs. 42.27 ± 40.31 [SD] HU, respectively; P = 0.007) and 2-min (70.93 ± 38.05 [SD] HU vs. 48.94 ± 41.83 [SD] HU, respectively; P = 0.016) after intravenous administration of contrast material. At 1-min after intravenous administration of contrast material, an optimal cut-off value of 54.43 HU was found to best discriminate between malignant and benign breast lesions (AUC = 0.681; 95%CI: 0.558–0.805; P = 0.006) yielding 69.0% sensitivity (95%CI: 56.9–79.5%) and 69.2% specificity (95% CI: 48.2–85.7%). At 2-min, an optimal cut-off value of 72.65 HU was found to best discriminate between malignant and benign breast lesions (AUC = 0.654; 95%CI: 0.535–0.774; P = 0.020) yielding 50.7% sensitivity (95%CI: 38.6–62.8%) and 80.8% specificity (95%CI: 60.6–93.4%). CE-CBCT helped differentiate between immunohistochemical subtypes of breast lesions with lowest enhancement for triple negative lesions. No differences in enhancement were found among histopathological subtypes lesions at 1-min (P = 0.478) and 2-min (P = 0.625).ConclusionCE-CBCT helps discriminate between malignant and benign breast lesions, with best capabilities obtained at 1-min after intravenous administration of contrast material. For malignant lesions, quantitative analysis of enhancement on CE-CBCT helps differentiate between immunohistochemical subtypes. 相似文献
87.
《European urology》2020,77(4):403-417
ContextAccurate staging of high-risk localised, advanced, and metastatic prostate cancer is becoming increasingly more important in guiding local and systemic treatment. Gallium-68 prostate-specific membrane antigen (PSMA) positron emission tomography (PET) has increasingly been utilised globally to assess the local and metastatic burden of prostate cancer, typically in biochemically recurrent or advanced disease. Following our previous meta-analysis, a high-volume series has been reported highlighting the utility of 68Ga-PSMA PET in this setting.ObjectiveTo perform a systematic review and meta-analysis to update reported predictors of positive 68Ga-PSMA PET according to prior therapy and proportion of positivity in various anatomical locations with sensitivity and specificity profiles.Evidence acquisitionWe performed critical reviews of MEDLINE, EMBASE, ScienceDirect, Cochrane Libraries, and Web of Science databases in July 2018 according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement. Quality assessment was performed using Quality Assessment if Diagnostic Accuracy Studies-2 tool. Meta-analyses of proportions were performed using a random-effect model. Summary sensitivity and specificity values were obtained by fitting bivariate hierarchical regression models.Evidence synthesisA total of 37 articles including 4790 patients were analysed. For patients with biochemical recurrence, positive 68Ga-PSMA PET scans increased with higher pre-PET prostate-specific antigen (PSA) levels. For PSA categories 0–0.19, 0.2–0.49, 0.5–0.99, 1–1.99, and ≥2 ng/ml, the percentages of positive scans were 33%, 45%, 59%, 75%, and 95%, respectively. No significant differences in positivity were noted between Gleason sums ≤7 and ≥8. Significant differences in positivity after biochemical recurrence in the prostate bed were noted between radical prostatectomy (22%) and radiotherapy (52%) patients. On per-node analysis, high sensitivity (75%) and specificity (99%) were observed.ConclusionsGa-68-PSMA PET improves detection of metastases with biochemical recurrence, particularly at low pre-PET PSA levels of >0.2 ng/ml (33%) and 0.2–0.5 ng/ml (45%). Ga-68-PSMA-PET produces favourable sensitivity and specificity profiles on meta-analysis of pooled data. This analysis highlights different anatomic patterns of metastatic spread according to PSMA PET in the primary and biochemically recurrent settings.Patient summaryGallium-68 prostate-specific membrane antigen positron emission tomography is now an established imaging technique that has been developed in response to inadequacies in standard of care imaging modalities to improve the detection of metastatic disease in prostate cancer, particularly in the setting of disease recurrence. To date, this imaging modality in the setting of primary staging is controversial, given the paucity of data. In light of the growing body of evidence, we summarised the data to date to provide clinicians with an overview of this imaging modality. 相似文献
88.
PurposeTo compare the sensitivity for breast cancer (BC) and BC size estimation of preoperative contrast-enhanced magnetic resonance imaging (CEMRI) versus combined unenhanced magnetic resonance imaging (UMRI) and digital breast tomosynthesis (DBT).Patients and methodsWe retrospectively included 56 women who underwent DBT and preoperative 1.5 T CEMRI between January 2016–February 2017. Three readers with 2–10 years of experience in CEMRI and DBT, blinded to pathology, independently reviewed CEMRI (diffusion-weighted imaging [DWI], T2-weighted imaging, pre- and post-contrast T1-weighted imaging) and a combination of UMRI (DWI and pre-contrast T1-weighted imaging) and DBT. We calculated per-lesion sensitivity of CEMRI and UMRI + DBT, and the agreement between CEMRI, UMRI and DBT versus pathology in assessing cancer size (Bland-Altman analysis). Logistic regression was performed to assess features predictive of cancer missing.ResultsWe included 70 lesions (64% invasive BC, 36% ductal carcinoma in situ or invasive BC with in situ component). UMRI + DBT showed lower sensitivity (86–89%) than CEMRI (94–100%), with a significant difference for the most experienced reader only (p = 0.008). False-positives were fewer with UMRI + DBT (4–5) than with CEMRI (18–25), regardless of the reader (p = 0.001–0.005). For lesion size, UMRI showed closer limits of agreement with pathology than CEMRI or DBT. Cancer size ≤1 cm was the only independent predictor for cancer missing for both imaging strategies (Odds ratio 8.62 for CEMRI and 19.16 for UMRI + DBT).ConclusionsUMRI + DBT showed comparable sensitivity and less false-positives than CEMRI in the preoperative assessment of BC. UMRI was the most accurate tool to assess cancer size. 相似文献
89.
目的探讨慢性荨麻疹发病与血清中食物特异性IgG抗体的关系。方法应用酶联免疫吸附试验(ELISA)检测111例慢性荨麻疹患者(慢性荨麻疹组)血清中食物特异性IgG抗体水平,并与30例健康受试者(对照组)资料进行对比研究。结果111例慢性荨麻疹患者中,食物特异性IgG抗体阳性79例(阳性率为71.17%),与对照组阳性率(43.33%)比较,差异有统计学意义(X2=8.071,P〈0.01)。且慢性荨麻疹组以鸡蛋特异性IgG抗体阳性率最高(51.35%),其次是虾(43.24%)、牛奶(38.74%)、螃蟹(34.23%)、大豆(27.93%),慢性荨麻疹组鸡蛋、虾、螃蟹、鳕鱼、大豆特异性IgG抗体阳性率与对照组比较,差异有统计学意义(P〈0.05)。结论食物特异性IgG抗体与慢性荨麻疹发病具有相关性,血清食物特异性IgG水平检测对慢性荨麻疹的预防和治疗具有重要意义。 相似文献
90.
目的:探讨结核感染T细胞斑点试验在脊柱结核诊断中的临床应用价值。方法选取2012年4月~2013年1月本院骨科病区收治的疑似脊柱结核患者156例,分别采用结核感染T细胞斑点试验和结核菌素试验进行诊断,比较两者对脊柱结核诊断的临床意义(包括灵敏性、特异性、假阳性率和假阴性率指标的差别)。结果结核感染T细胞斑点试验的灵敏性和特异性明显高于结核菌素试验(P<0.05);同时,结核感染T细胞斑点试验的假阳性率和假阴性率明显低于结核菌素试验试验(P<0.05)。结论结核感染T细胞斑点试验在诊断脊柱结核中具有良好的敏感性和特异性,具有重要临床应用价值。 相似文献