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41.
High-sensitivity troponin assay brought new challenges as we detect elevated concentration in many other diseases, and it became difficult to distinguish the real cause of this elevation. In this notion, diagnosis of acute coronary syndrome (ACS) remains a challenge in emergency department (ED).We aim to examine different approaches for rule-in and rule-out of ACS using risk scores, copeptin, and coronary computed tomography angiography (CCTA).A prospective observational study was designed to evaluate chest pain patients. Consecutive adult patients admitted to the ED with a chief complaint of chest pain due to any cause were included.All patients were followed-up for 6 months after discharge for major adverse cardiovascular events and readmissions. Admission data, ED processes, and diagnoses were analyzed.One hundred forty-six patients were included, average age was 63 ± 13.4 years, and 95 (65.1%) were male. Global Registry of Acute Coronary Events (GRACE) and History, ECG, Age, Risk factors, Troponin (HEART) scores showed good prognostic abilities, but HEART combination with copeptin improves diagnoses of myocardial infarction (area under the curve [AUC] 0.764 vs AUC 0.864 P = .0008). Patients with elevated copeptin were older, had higher risk scores, and were more likely to be admitted to hospital and diagnosed with ACS in ED. For copeptin, AUC was 0.715 (95% confidence interval 0.629–0.803), and for combination with troponin, AUC of 0.770 (0.703–0.855) did not improve rule-in of myocardial infarction. High-sensitivity troponin I assay alongside prior stroke, history of carotid stenosis, dyslipidemia, use of diuretics, and electrocardiogram changes (left bundle branch block or ST depression) are good predictors of myocardial infarction (χ² = 52.29, AUC = 0.875 [0.813–0.937], P < .001). The regression analysis showed that combination of copeptin and CCTA without significant stenosis can be used for ACS rule-out (χ² = 26.36, P < .001, AUC = 0.772 [0.681–0.863], negative predictive value of 96.25%).For rule-in of ACS, practitioner should consider not only scores for risk stratification but carefully analyze medical history and nonspecific electrocardiogram changes and even with normal troponin results, we strongly suggest thorough evaluation in chest pain unit. For rule-out of ACS combination of copeptin and CCTA holds great potential.  相似文献   
42.
To tune and test the generalizability of a deep learning-based model for assessment of COVID-19 lung disease severity on chest radiographs (CXRs) from different patient populations.A published convolutional Siamese neural network-based model previously trained on hospitalized patients with COVID-19 was tuned using 250 outpatient CXRs. This model produces a quantitative measure of COVID-19 lung disease severity (pulmonary x-ray severity (PXS) score). The model was evaluated on CXRs from 4 test sets, including 3 from the United States (patients hospitalized at an academic medical center (N = 154), patients hospitalized at a community hospital (N = 113), and outpatients (N = 108)) and 1 from Brazil (patients at an academic medical center emergency department (N = 303)). Radiologists from both countries independently assigned reference standard CXR severity scores, which were correlated with the PXS scores as a measure of model performance (Pearson R). The Uniform Manifold Approximation and Projection (UMAP) technique was used to visualize the neural network results.Tuning the deep learning model with outpatient data showed high model performance in 2 United States hospitalized patient datasets (R = 0.88 and R = 0.90, compared to baseline R = 0.86). Model performance was similar, though slightly lower, when tested on the United States outpatient and Brazil emergency department datasets (R = 0.86 and R = 0.85, respectively). UMAP showed that the model learned disease severity information that generalized across test sets.A deep learning model that extracts a COVID-19 severity score on CXRs showed generalizable performance across multiple populations from 2 continents, including outpatients and hospitalized patients.  相似文献   
43.
A 45‐year‐old woman developed chest pain on the previous day. High‐attenuation mucus in the bronchus was found on the CT examination on admission, which led to a diagnosis of allergic bronchopulmonary mycosis. CT should be checked carefully for high‐attenuation mucus because this finding is highly specific for allergic bronchopulmonary mycosis.  相似文献   
44.
Chest tubes are routinely inserted after thoracic surgery procedures in different sizes and numbers. The aim of this study is to assess the efficacy of Smart Drain Coaxial drainage compared with two standard chest tubes in patients undergoing thoracotomy for pulmonary lobectomy. Ninety-eight patients (57 males and 41 females, mean age 68.3 ± 7.4 years) with lung cancer undergoing open pulmonary lobectomy were randomized in two groups: 50 received one upper 28-Fr and one lower 32-Fr standard chest tube (ST group) and 48 received one 28-Fr Smart Drain Coaxial tube (SDC group). Hospitalization, quantity of fluid output, air leaks, radiograph findings, pain control and costs were assessed. SDC group showed shorter hospitalization (7.3 vs. 6.1 days, p = 0.02), lower pain in postoperative day-1 (p = 0.02) and a lower use of analgesic drugs (p = 0.04). Pleural effusion drainage was lower in SDC group in the first postoperative day (median 400.0 ± 200.0 mL vs. 450.0 ± 193.8 mL, p = 0.04) and as a mean of first three PODs (median 325.0 ± 137.5 mL vs. 362.5 ± 96.7 mL, p = 0.01). No difference in terms of fluid retention, residual pleural space, subcutaneous emphysema and complications after chest tubes removal was found. In conclusion, Smart Drain Coaxial chest tube seems a feasible option after thoracotomy for pulmonary lobectomy. The SDC group showed a shorter hospitalization and decreased analgesic drugs use and, thus, a reduction of costs.  相似文献   
45.
中上段食管癌超胸顶吻合的应用   总被引:1,自引:0,他引:1  
彭康宁  张荣新  朱金海 《安徽医药》2011,15(9):1112-1114
目的 探讨超胸顶吻合法在中上段食管癌中应用的意义.方法 随机选择该科自2006年8月以来,手术切除中上段食管癌82例.共分为A、B组.A组48例,采用超胸顶吻合;B组34例,采用颈部吻合.结果 喉返神经损伤 A组0例,B组6例;两组手术时间分别为(3.0±0.3),(3.8±0.8) h,t=6.15,P<0.05,两...  相似文献   
46.
目的介绍隆乳术中乳房假体容积选择的一种简易、实用万法。 方法30例接受硅胶囊假体隆乳术的女性,分别随访记录身高、体重、腰围、臀围、假体容积、术前术后经乳头胸围及经乳房下皱襞胸围,并将经乳头胸围的增加量与上述变量进行多元相关回归分析。 结果隆乳术后经乳头胸围的增加量与假体容积及经乳房下皱襞胸围的大小关系密切,经乳头胸围的增加量=6.6832+0.0743×假体容积-0.2187×乳房下皱襞胸围。 结论隆乳术中假体的选择除了要考虑受术者的身高、体重等因素,更重要的是其胸廓和乳房的发育状况。根据经乳房下皱襞胸围大小和预期的术后经乳头胸围的增加量,可以推算所需假体的容积。  相似文献   
47.
目的X线胸片中肺野的准确分割是胸片图像自动分析的必要步骤。本文采用局部特征的密集匹配和标号融合进行胸片
肺野的自动分割。方法对于输入的待分割胸片,基于每个像素点提取密集SIFT描述子和图像块作为局部特征,采用密集匹配
直接在整个参考图像特征集合中快速搜索近邻;密集匹配分为受限的随机初始化、近邻场传播和受限的随机搜索三步,并数次
迭代后两步。利用匹配得到的近邻场,提取标号图像块并进行加权,权重为匹配的相似度,最后重组为肺野的概率图,经阈值化
处理即可得到肺野的分割。结果在公开的JSRT胸片图像数据集上进行测试,本文方法的Jaccard指标可达95.5%。结论利用
局部特征的密集匹配和标号融合能取得准确性高且稳定的胸片肺野分割效果,并且优于当前最好的胸片肺野分割方法。
  相似文献   
48.
刘彬  赵新  白玫 《医疗卫生装备》2011,32(5):96-97,101
目的:探讨迈瑞DigiEye760医用数字X射线摄影系统所采用的3种不同图像后处理方法对图像质量与辐射剂量优化的影响。方法:采用对比度阈值测试模块TO20和数字胸部X射线摄影QC体模Model 07-646,测试不同曝光条件及不同图像后处理模式下图像的阈值对比度细节探测力。结果:原始图像受曝光条件的影响较为明显,经过图像后处理和细节增强后,曝光条件对图像质量的影响减轻甚至消失。对于图像对比度细节探测力指数来说,Esa要好于原始图像,增强模式要好于Esa模式;随着曝光管电流的增大,强增强模式提高图像质量的效果逐渐减弱,当曝光管电流提高至200 mA时,强增强模式与弱增强模式具有相同的阈值对比度细节探测力。结论:图像后处理模式可以在较低曝光剂量条件下取得较好的图像阈值对比度细节探测力。只有选取适合的曝光条件,才能做到成像质量与辐射剂量的最大程度优化。  相似文献   
49.
目的:探讨正弦图确定迭代重建(SAFIRE)技术在降低胸部扫描剂量中的应用价值。方法选取2013年11月于我院作胸部CT检查的80例患者,将患者随机分成两组(对照组和低剂量组),每组各40人。对照组采用管电压130 kV和滤波反投影(FBP)重建技术,低剂量组采用管电压80 kV和SAFIRE(Strength 3级)技术。分别测量两组气管分杈层面降主动脉和同层背部肌肉的CT值及其标准差(SD)、信噪比(SNR)、对比噪声比(CNR);记录两组患者的CT剂量指数(CTDI)、剂量长度乘积(DLP),并估算有效剂量(ED)。由两名医师对图像质量采用5分制进行评估,并用Kappa检验评价医师评分结果的一致性。结果对照组的CTDI为(6.71±1.06)mGy,DLP为(237.75±45.76) mGy·cm,ED为(3.33±0.64) mSv;低剂量组的CTDI为(2.08±0.28) mGy, DLP为(78.53±11.35) mGy·cm,ED为(1.10±0.16) mSv;两组差异均有统计学意义(P<0.05)。对照组的SNR为(6.84±1.83),CNR为(2.25±1.05);低剂量组的SNR为(6.43±1.32),CNR为(1.99±1.41),两组差异均无统计学意义(P>0.05)且图像质量均能满足临床诊断要求,医师间的评估结果具有较好的一致性(Kappa=0.764)。结论胸部低剂量CT结合SAFIRE技术,可在不影响诊断效果的情况下,显著降低辐射剂量。  相似文献   
50.
目的 探讨胸痛特征诊断冠心病的准确性.方法 连续入组2012年6月至2016年6月经过冠状动脉造影(CAG)和冠状动脉血流储备分数(FFR)检查的住院患者240例,根据临床病史的描述将患者分成无胸痛组(55例),不典型胸痛组(79例),典型劳力心绞痛组(64例)和支架植入组(42例).将不同胸痛性质与CAG和FFR进行...  相似文献   
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