X-Ray computed tomography

X 线计算机断层扫描
  • 文章类型: Journal Article
    使用X射线计算机断层扫描和性能测量研究了未掺杂和Na掺杂的SnSe样品的热循环对微观结构和热电性能的影响。据观察,热循环会导致明显的裂纹发展,这会降低电导率和晶格热导率,但不会影响热功率。在重复热处理之后,ZT值急剧降低。重要的是考虑循环期间的密度变化以获得热导率的精确值。甚至在热循环之前,火花等离子体烧结(SPS)样品具有显著数量的微裂纹。SPS颗粒中裂纹的取向及其对微观结构的影响受到富含Na杂质的影响。没有杂质的SnSe和Sn0.995Na0.005Se样品出现裂纹,并表现出平行于颗粒表面的晶粒生长,也是2DSnSe层的平面。含有杂质的Sn0.97Na0.03Se样品产生与颗粒表面正交的裂纹。Sn0.97Na0.03Se中的这种裂纹取向抑制了晶粒生长。所有样品在热循环后表现出机械不稳定。
    Effects of thermal cycling on the microstructure and thermoelectric properties are studied for the undoped and Na-doped SnSe samples using X-ray computed tomography and property measurements. It is observed that thermal cycling causes significant cracks to develop, which decrease both the electrical and lattice thermal conductivities but do not affect the thermopower. The zT values are drastically reduced after the repeated heat treatment. It is important to account for density changes during cycling to obtain accurate values of the thermal conductivity. Even before thermal cycling, the spark-plasma sintered (SPS) samples have a significant number of microcracks. The orientation of cracks within the SPS pellets and their effect on the microstructure are influenced by the presence of a Na-rich impurity. The SnSe and Sn0.995Na0.005Se samples without the impurity develop cracks and exhibit grain growth parallel to the pellet surface, which is also the plane of the 2D SnSe layers. The Sn0.97Na0.03Se sample containing the impurity develops cracks that are orthogonal to the pellet surface. Such an orientation of cracks in Sn0.97Na0.03Se inhibits grain growth. All samples appear mechanically unstable after thermal cycling.
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  • 文章类型: Journal Article
    微计算机断层扫描(µCT)系统用于检查各种物体的内部结构,如材料样本,制造零件,和自然物体。在体素数据中解决精细细节或执行准确的几何测量关键取决于μCT系统几何结构的精确校准。本文介绍了一种使用校准体模投影的µCT系统校准方法,其中体模的坐标最初是未知的。该方法涉及检测和跟踪钢球轴承以及使用非线性最小二乘优化调整未知系统几何参数。测试多个几何模型以验证它们对自校准方法的适用性。使用以不同放大倍数捕获的校准体模来测试实现。结果表明,系统能够确定几何模型参数,而检测器上的剩余误差在0.27px和0.18px之间。校准后仍然存在的系统误差,以及由于系统不稳定而改变参数,正在调查。这项工作的源代码已发布,以便进行进一步的研究。
    Micro-Computed Tomography (µCT) systems are used for examining the internal structures of various objects, such as material samples, manufactured parts, and natural objects. Resolving fine details or performing accurate geometric measurements in the voxel data critically depends on the precise calibration of the µCT systems geometry. This paper presents a calibration method for µCT systems using projections of a calibration phantom, where the coordinates of the phantom are initially unknown. The approach involves detecting and tracking steel ball bearings and adjusting the unknown system geometry parameters using non-linear least squares optimization. Multiple geometric models are tested to verify their suitability for a self-calibration approach. The implementation is tested using a calibration phantom captured at different magnifications. The results demonstrate the system\'s capability to determine the geometry model parameters with a remaining error on the detector between 0.27 px and 0.18 px. Systematic errors that remain after calibration, as well as changing parameters due to system instabilities, are investigated. The source code of this work is published to enable further research.
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  • 文章类型: Journal Article
    本文介绍了自密实混凝土(SCC)分层浇筑技术对板层构件层间粘结承载力的影响。对尺寸为750×750×150mm的平板单元进行了研究,从混凝土交付的单点浇筑。这项研究的目的是分析混凝土顶层的高度对层间粘结强度的影响。这项研究利用了50、75和100毫米的顶层高度,which,根据作者的经验,是制作板元素时最常见的情况。通过研究从混凝土板上切下的立方试样的劈裂抗拉强度来确定层间粘结。采用计算机断层扫描(CT)对混凝土层之间的接触区进行成像。通过对CT影像及强度检测结果的分析,结果表明,层间粘结受顶层高度及其与铸造点的自由扩散距离的影响。随着顶层高度的降低和与混合物供应点的距离的增加,观察到层间粘合强度的降低。所获得的关系是线性的并且具有明显的负斜率。结论是,SCC多层铸造的有效建议和标准过于笼统。因此,我们建议详细说明减少冷关节风险的建议,这降低了层间接头的粘结强度。
    This paper presents a study on the influence of the layered casting technology of self-compacting concrete (SCC) on the load-bearing capacity of interlayer bond in slab elements. The research was conducted on slab elements with dimensions of 750 × 750 × 150 mm, concreted from a single point of concrete delivery. The aim of this study was to analyse the influence of the height of the concreting top layer on the bond strength between the layers. The study utilised top layer heights of 50, 75, and 100 mm, which, according to the authors\' experience, are the most common cases when making slab elements. The interlayer bond was determined by investigating the splitting tensile strength of cubic specimens cut from the concrete slabs. Computed tomography (CT) was employed to image the contact zone between the concrete layers. Based on the analysis of the CT imaging and the results of the strength tests, it was shown that the interlayer bond is influenced by both the height of the top layer and its free-spread distance from the casting point. A reduction in the interlayer bond strength was observed with decreasing the height of the top layer and increasing distance from the mixture supply point. The relationships obtained were linear and had a clearly negative slope. It was concluded that the valid recommendations and standards for the multilayer casting of SCC are too general. Therefore, we propose to detail the recommendations to reduce the risk of cold joints, which diminish the bond strength of the interlayer joints.
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  • 文章类型: Journal Article
    电纺纤维素吸附剂是作为常规填充床色谱法的类似物应用于各种生物过程分离的新兴材料。电纺吸附剂已被证明是有效的快速循环介质,实现蛋白质和病毒载体的高通量分离,而不影响选择性和回收率。然而,目前缺乏有关操作和控制具有功能和性能的电纺吸附剂结构的知识,以满足新兴的分离需求,多样化的生物制品。在这项研究中,通过调整其制造条件制备了一系列电纺纤维素吸附剂。通过改变静电纺丝聚合物溶液产生纤维直径范围(400至600nm)。此外,通过改变静电纺丝片材上的层压压力来实现孔隙率范围(0.4至0.7v/v)。用不同程度的季胺配体密度将吸附剂官能化以产生18个原型阴离子交换剂。通过BET氮吸附表面积对其形貌进行表征,X线计算机断层扫描,毛细管流量测量和扫描电子显微镜测量。吸附剂的物理特性用于适应的半经验模型中,并与测得的渗透率数据进行比较。原型的渗透率范围为10-2至10-4mDarcy。测量的数据显示对建模数据的良好粘附性,在获得湿吸附剂特性而不是干燥材料方面可能有所改善。最后,表征了电纺吸附剂对不同大小(直径为3.5nm和8.9nm)的模型蛋白和质粒DNA的结合能力。蛋白质和质粒DNA的静态结合能力在5mg/ml至25mg/ml的范围内,并且基于BET表面积显示与单层覆盖率的偏差<20%。因此,结论是,电纺吸附剂最有可能以最小的空间位阻在表面上吸附蛋白质和质粒DNA的单层。
    Electrospun cellulose adsorbents are an emergent class of materials applied to a variety of bioprocess separations as an analogue to conventional packed bed chromatography. Electrospun adsorbents have proven to be effective as rapid cycling media, enabling high throughput separation of proteins and viral vectors without compromising selectivity and recovery. However, there is a current lack of knowledge in relation to the manipulation and control of electrospun adsorbent structure with function and performance to cater to the separation needs of emerging, diverse biological products. In this study, a series of electrospun cellulose adsorbents were fabricated by adjusting their manufacturing conditions. A range of fiber diameters (400 to 600 nm) was created by changing the electrospinning polymer solution. Additionally, a range of porosities (0.4 to 0.7 v/v) was achieved by varying the laminating pressures on the electrospun sheets. The adsorbents were functionalized with different degrees of quaternary amine ligand density to create 18 prototype anion exchangers. Their morphology was characterized by BET nitrogen adsorption surface area, X-ray computed tomography, capillary flow porometry and scanning electron microscopy measurements. The physical characteristics of the adsorbents were used in an adapted semi-empirical model and compared to measured permeability data. Permeabilities of prototypes ranged from 10-2 to 10-4 mDarcy. The measured data showed good adherence to modelled data with possible improvements in acquiring wet adsorbent characteristics instead of dried material. Finally, the electrospun adsorbents were characterized for their binding capacity of model proteins of different sizes (diameters of 3.5 nm and 8.9 nm) and plasmid DNA. Static binding capacities ranged from 5 mg/ml to 25 mg/ml for the proteins and plasmid DNA and showed <20 % deviation from monolayer coverage based on BET surface area. Therefore, it was concluded that the electrospun adsorbents most likely adsorb monolayers of proteins and plasmid DNA on the surface with minimal steric hindrance.
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  • 文章类型: Journal Article
    恶性胸腔积液(MPE)是一个常见的临床问题,需要通过侵入性检查获得细胞学和/或组织学确认以建立明确的诊断。影像组学正在迅速发展,可以提供一种非侵入性工具来识别MPE。
    我们旨在开发一种基于从未增强的胸部计算机断层扫描(CT)图像中提取的影像组学特征的模型,并研究其在预测MPE中的价值。
    这项回顾性研究纳入了2016年1月至2020年6月的胸腔积液患者。人工气胸后所有患者均行胸部CT扫描和内科胸腔镜检查。将病例分为训练队列和测试队列,分别进行建模和验证。应用Mann-WhitneyU检验和最小绝对收缩和选择算子(LASSO)来确定最佳特征。我们建立了基于支持向量机(SVM)的影像组学模型,并使用ROC和校准曲线分析评估了其性能。
    纳入了29例MPE患者和52例非MPE患者。从每个样本中定量提取了944个放射学特征,并在选择后减少到14个特征进行建模。在培训和测试队列中,影像组学模型的AUC分别为0.96(95%CI:0.912-0.999)和0.86(95%CI:0.657〜1.000),分别。模型的校准曲线在预测和实际数据之间具有良好的一致性。
    基于未增强胸部CT的影像组学模型对预测MPE具有良好的性能,可能为医生在临床决策中提供强大的工具。
    UNASSIGNED: Malignant pleural effusion (MPE) is a common clinical problem that requires cytological and/or histological confirmation obtained by invasive examination to establish a definitive diagnosis. Radiomics is rapidly evolving and can provide a non-invasive tool to identify MPE.
    UNASSIGNED: We aimed to develop a model based on radiomic features extracted from unenhanced chest computed tomography (CT) images and investigate its value in predicting MPE.
    UNASSIGNED: This retrospective study included patients with pleural effusions between January 2016 and June 2020. All patients underwent a chest CT scanning and medical thoracoscopy after artificial pneumothorax. Cases were divided into a training cohort and a test cohort for modelling and verifying respectively. The Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) were applied to determine the optimal features. We built a radiomics model based on support vector machines (SVM) and evaluated its performance using ROC and calibration curve analysis.
    UNASSIGNED: Twenty-nine patients with MPE and fifty-two patients with non-MPE were enrolled. A total of 944 radiomic features were quantitatively extracted from each sample and reduced to 14 features for modeling after selection. The AUC of the radiomics model was 0.96 (95% CI: 0.912-0.999) and 0.86 (95% CI: 0.657~1.000) in the training and test cohorts, respectively. The calibration curves for model were in good agreement between predicted and actual data.
    UNASSIGNED: The radiomics model based on unenhanced chest CT has good performance for predicting MPE and may provide a powerful tool for doctors in clinical decision-making.
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  • 文章类型: Journal Article
    目的:使用来自不使用造影剂的双能CT(DECT)的定量数据,创建用于区分良性和恶性肝脏病变的预测模型(PM)。
    方法:这项回顾性研究包括接受DECT的肝脏病变患者,包括非对比增强扫描。良性病变包括肝血管瘤,而恶性病变包括肝细胞癌,转移性肝癌,和肝内胆管细胞癌。将患者分为推导组和验证组。在派生组中,两个放射科医生使用单变量和多变量逻辑回归计算了十个多参数数据以生成PM。在验证组中,另外两名放射科医生测量了参数以评估PMs的诊断性能。
    结果:该研究包括121名连续患者(平均年龄67.4±13.8岁,80男性),衍生组97(良性25例,恶性72例),验证组24例(良性7例,恶性17例)。过采样将良性病变样本增加到75,等于恶性组的PM。所有参数在单变量分析中都有统计学意义(所有p<0.05),导致在多变量分析中创建了五个PM。两个观察者的五个PM的曲线下面积如下:PM1(斜率K,血)=0.76,0.74;PM2(斜率K,脂肪)=0.55,0.51;PM3(有效Z差,血)=0.75,0.72;PM4(斜率K,血,脂肪)=0.82,0.78;和PM5(斜率K,有效-Z差,血)=0.90,0.87。PM5产生了最好的诊断性能。
    结论:多参数非对比增强DECT是区分肝脏病变的一种非常有效的方法。
    结论:使用非对比增强DECT对于区分良性和恶性肝脏病变非常有用。这种方法使医生能够计划更好的治疗策略,缓解与对比过敏相关的担忧,造影剂肾病,辐射暴露,以及过高的医疗费用。
    结论:用非增强CT区分良性和恶性肝脏病变是可取的。这个模型,结合坡度K,有效Z,和血液定量,区分良性和恶性肝脏病变。非对比增强DECT有好处,特别是对碘过敏的患者,肾功能衰竭,或者哮喘.
    OBJECTIVE: To create prediction models (PMs) for distinguishing between benign and malignant liver lesions using quantitative data from dual-energy CT (DECT) without contrast agents.
    METHODS: This retrospective study included patients with liver lesions who underwent DECT, including non-contrast-enhanced scans. Benign lesions included hepatic hemangioma, whereas malignant lesions included hepatocellular carcinoma, metastatic liver cancer, and intrahepatic cholangiocellular carcinoma. Patients were divided into derivation and validation groups. In the derivation group, two radiologists calculated ten multiparametric data using univariate and multivariate logistic regression to generate PMs. In the validation group, two additional radiologists measured the parameters to assess the diagnostic performance of PMs.
    RESULTS: The study included 121 consecutive patients (mean age 67.4 ± 13.8 years, 80 males), with 97 in the derivation group (25 benign and 72 malignant) and 24 in the validation group (7 benign and 17 malignant). Oversampling increased the benign lesion sample to 75, equalizing the malignant group for building PMs. All parameters were statistically significant in univariate analysis (all p < 0.05), leading to the creation of five PMs in multivariate analysis. The area under the curve for the five PMs of two observers was as follows: PM1 (slope K, blood) = 0.76, 0.74; PM2 (slope K, fat) = 0.55, 0.51; PM3 (effective-Z difference, blood) = 0.75, 0.72; PM4 (slope K, blood, fat) = 0.82, 0.78; and PM5 (slope K, effective-Z difference, blood) = 0.90, 0.87. PM5 yielded the best diagnostic performance.
    CONCLUSIONS: Multiparametric non-contrast-enhanced DECT is a highly effective method for distinguishing between liver lesions.
    CONCLUSIONS: The utilization of non-contrast-enhanced DECT is extremely useful for distinguishing between benign and malignant liver lesions. This approach enables physicians to plan better treatment strategies, alleviating concerns associated with contrast allergy, contrast-induced nephropathy, radiation exposure, and excessive medical expenses.
    CONCLUSIONS: Distinguishing benign from malignant liver lesions with non-contrast-enhanced CT would be desirable. This model, incorporating slope K, effective Z, and blood quantification, distinguished benign from malignant liver lesions. Non-contrast-enhanced DECT has benefits, particularly in patients with an iodine allergy, renal failure, or asthma.
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  • 文章类型: Journal Article
    目的:评估头颅对比增强(CE)CT的静脉碘化对比剂(ICM)使用与辐射剂量之间的关系,胸部,和腹部骨盆(AP)在国际上,多中心设置。
    方法:我们的国际(n=16个国家),多中心(n=43个站点),横断面(ConRad)研究分为两部分。第1部分:关于CT和ICM制造商/品牌和各自协议相关信息的Redcap调查。第2部分:3,258名患者(18-96岁;M:F1654:1604)接受常规头部CECT(n=456)的信息,胸部(n=528),AP(n=599),头颅CT血管造影(n=539),肺栓塞(n=599),在五大洲的43个地点进行了肝脏CT检查(n=537)。记录了以下信息:医院名称,患者年龄,性别,体重指数[BMI],临床适应症,扫描参数(扫描阶段数,kV),IV-对比信息(浓度,volume,流量,和延迟),和剂量指数(CTDIvol和DLP)。
    结果:大多数常规胸部(58.4%)和AP(68.7%)的CECT检查均以2-4个扫描阶段进行,扫描延迟固定(胸部71.4%;AP79.8%,ICM给药后肝脏CECT50.7%)。大多数站点在不同的患者和扫描阶段没有改变kV;大多数CECT方案在120-140kV下进行(83%,1979/2685)。非对比(CTDIvol24[16-30]mGy;DLP633[414-702]mGy·cm)和对比后阶段(22[19-27]mGy;648[392-694]mGy·cm)的辐射剂量之间没有显着差异(p=0.142)。对于胸部和APCECT使用推注跟踪的部位具有比具有固定扫描延迟的部位更低的CTDIvol(p<0.001)。BMI与CTDIvol之间无相关性(r2≤-0.1至0.1,p=0.931)。
    结论:我们的研究表明,在不同的CT方案中,ICM注射方案和辐射剂量的差异高达10倍。该研究强调需要优化CT扫描和对比方案,以减少患者不必要的对比和辐射暴露。
    结论:CT方案中ICM介质和辐射剂量的广泛可变性和缺乏标准化,这表明需要对对比剂使用和扫描因素进行教育和优化,以优化CECT的图像质量。
    结论:缺乏主要考虑患者大小的以患者为中心的CT方案优化。在整个CT协议中,ICM体积与CT辐射剂量之间缺乏相关性。对于相同的CT方案,地点的碘负荷有十倍的变化表明缺乏标准化。
    OBJECTIVE: To assess the relationship between intravenous iodinated contrast media (ICM) administration usage and radiation doses for contrast-enhanced (CE) CT of head, chest, and abdomen-pelvis (AP) in international, multicenter settings.
    METHODS: Our international (n = 16 countries), multicenter (n = 43 sites), and cross-sectional (ConRad) study had two parts. Part 1: Redcap survey with questions on information related to CT and ICM manufacturer/brand and respective protocols. Part 2: Information on 3,258 patients (18-96 years; M:F 1654:1604) who underwent CECT for a routine head (n = 456), chest (n = 528), AP (n = 599), head CT angiography (n = 539), pulmonary embolism (n = 599), and liver CT examinations (n = 537) at 43 sites across five continents. The following information was recorded: hospital name, patient age, gender, body mass index [BMI], clinical indications, scan parameters (number of scan phases, kV), IV-contrast information (concentration, volume, flow rate, and delay), and dose indices (CTDIvol and DLP).
    RESULTS: Most routine chest (58.4%) and AP (68.7%) CECT exams were performed with 2-4 scan phases with fixed scan delay (chest 71.4%; AP 79.8%, liver CECT 50.7%) following ICM administration. Most sites did not change kV across different patients and scan phases; most CECT protocols were performed at 120-140 kV (83%, 1979/2685). There were no significant differences between radiation doses for non-contrast (CTDIvol 24 [16-30] mGy; DLP 633 [414-702] mGy·cm) and post-contrast phases (22 [19-27] mGy; 648 [392-694] mGy·cm) (p = 0.142). Sites that used bolus tracking for chest and AP CECT had lower CTDIvol than sites with fixed scan delays (p < 0.001). There was no correlation between BMI and CTDIvol (r2 ≤ - 0.1 to 0.1, p = 0.931).
    CONCLUSIONS: Our study demonstrates up to ten-fold variability in ICM injection protocols and radiation doses across different CT protocols. The study emphasizes the need for optimizing CT scanning and contrast protocols to reduce unnecessary contrast and radiation exposure to patients.
    CONCLUSIONS: The wide variability and lack of standardization of ICM media and radiation doses in CT protocols suggest the need for education and optimization of contrast usage and scan factors for optimizing image quality in CECT.
    CONCLUSIONS: There is a lack of patient-centric CT protocol optimization taking into consideration mainly patients\' size. There is a lack of correlation between ICM volume and CT radiation dose across CT protocol. A ten-fold variation in iodine-load for the same CT protocol in sites suggests a lack of standardization.
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  • 文章类型: Journal Article
    目标:计算机视觉(CV)模仿人类视觉,使计算机能够自动将最近检查的放射图像与大型图像数据库进行比较,以进行唯一识别,在涉及未知患者或死者的紧急情况下至关重要。本研究旨在使用单个CT切片将基于CV的个人识别方法从正交图(OPG)扩展到计算机断层扫描(CT)检查。
    方法:该研究分析了722名患者的819次头颅计算机断层扫描(CCT)检查,专注于来自六个解剖区域的单个CT切片,以探索它们在69例手术中基于CV的个人识别的潜力。CV自动识别和描述图像中的有趣特征,可以在参考图像中识别,然后指定为匹配点。在这项研究中,匹配点的数量被用作识别的指标.
    结果:在六个不同地区,在700多个可能的身份中,识别率从41/69(59%)到69/69(100%)不等。来自同一个人的图像比较获得了更高的匹配点,平均6.32±0.52%(100%代表最大可能匹配点),而不同个体的图像平均为0.94±0.15%。在牙齿中找到可靠的匹配点,上颌骨,颈椎,头骨,和鼻旁窦,上颌窦和筛细胞由于其丰富的匹配点而特别适合鉴定。
    结论:基于单个CT切片可以实现对个体的明确识别,上颌窦CT切片的识别率最高。然而,金属制品,尤其是牙齿修复术,和各种头部位置可以阻碍识别。
    结论:放射学拥有许多CV数据库的参考图像,在紧急检查或涉及未知死者的情况下,促进基于CV的自动个人身份识别。这通过允许访问病史来增强患者护理和与亲属的沟通。
    结论:放射学或法医学领域的未知个体构成了挑战,通过自动基于CV的识别方法解决。突出显示上颌窦的单个CT切片对于个人识别特别有效。放射学通过利用其广泛的图像数据库在自动个人识别中起着关键作用。
    OBJECTIVE: Computer vision (CV) mimics human vision, enabling computers to automatically compare radiological images from recent examinations with a large image database for unique identification, crucial in emergency scenarios involving unknown patients or deceased individuals. This study aims to extend a CV-based personal identification method from orthopantomograms (OPGs) to computed tomography (CT) examinations using single CT slices.
    METHODS: The study analyzed 819 cranial computed tomography (CCT) examinations from 722 individuals, focusing on single CT slices from six anatomical regions to explore their potential for CV-based personal identification in 69 procedures. CV automatically identifies and describes interesting features in images, which can be recognized in a reference image and then designated as matching points. In this study, the number of matching points was used as an indicator for identification.
    RESULTS: Across six different regions, identification rates ranged from 41/69 (59%) to 69/69 (100%) across over 700 possible identities. Comparison of images from the same individual achieved higher matching points, averaging 6.32 ± 0.52% (100% represents the maximum possible matching points), while images of different individuals averaged 0.94 ± 0.15%. Reliable matching points are found in the teeth, maxilla, cervical spine, skull bones, and paranasal sinuses, with the maxillary sinuses and ethmoidal cells being particularly suitable for identification due to their abundant matching points.
    CONCLUSIONS: Unambiguous identification of individuals based on a single CT slice is achievable, with maxillary sinus CT slices showing the highest identification rates. However, metal artifacts, especially from dental prosthetics, and various head positions can hinder identification.
    CONCLUSIONS: Radiology possesses a multitude of reference images for a CV database, facilitating automated CV-based personal identification in emergency examinations or cases involving unknown deceased individuals. This enhances patient care and communication with relatives by granting access to medical history.
    CONCLUSIONS: Unknown individuals in radiology or forensics pose challenges, addressed through automatic CV-based identification methods. A single CT slice highlighting the maxillary sinuses is particularly effective for personal identification. Radiology plays a pivotal role in automated personal identification by leveraging its extensive image database.
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  • 文章类型: Journal Article
    目的:建立基于常规CT征象和肿瘤微环境免疫类型(TIMT)的模型,以预测非小细胞肺癌(NSCLC)术后辅助化疗的持续临床获益(DCB)。
    方法:205例非小细胞肺癌患者术前接受CT检查,分为两组:DCB(无进展生存期(PFS)≥18个月)和非DCB(NDCB,PFS<18个月)。对PD-L1和CD8+肿瘤浸润淋巴细胞(TIL)的密度百分位数进行定量以估计TIMT。收集临床特征和常规CT征象。采用多变量逻辑回归来选择最有区别的参数,构建一个预测模型,并将模型可视化为列线图。接收器工作特性(ROC)曲线,校正曲线,和决策曲线分析(DCA)用于评估预测性能和临床效用。
    结果:118例DCB和87例NDCBNSCLC患者接受术后辅助化疗。DCB组和NDCB组之间的TIMT差异有统计学意义(P<0.05)。临床特征(神经元特异性烯醇化酶,鳞状细胞癌抗原,Ki-76和cM期)和常规CT征象(棘突,泡沫般的透明度,胸膜回缩,最大直径,和静脉相的CT值)在四个TIMT组之间存在差异(P<0.05)。此外,DCB组和NDCB组的临床特征(淋巴细胞计数[LYMPH]和cM分期)和常规CT征象(气泡样透明和胸腔积液)存在差异(P<0.05)。多变量分析表明,TIMT,cM阶段,LYMPH,和胸腔积液与DCB独立相关,并用于构建列线图。联合模型的曲线下面积(AUC)为0.70(95CI:0.64-0.76),敏感性和特异性分别为0.73和0.60。
    结论:常规CT征象和TIMT为预测NSCLC术后辅助化疗患者的临床结局提供了一种有希望的方法。
    OBJECTIVE: To develop a model based on conventional CT signs and the tumor microenvironment immune types (TIMT) to predict the durable clinical benefits (DCB) of postoperative adjuvant chemotherapy in non-small cell lung cancer (NSCLC).
    METHODS: A total of 205 patients with NSCLC underwent preoperative CT and were divided into two groups: DCB (progression-free survival (PFS) ≥ 18 months) and non-DCB (NDCB, PFS <18 months). The density percentiles of PD-L1 and CD8 + tumor-infiltrating lymphocytes (TIL) were quantified to estimate the TIMT. Clinical characteristics and conventional CT signs were collected. Multivariate logistic regression was employed to select the most discriminating parameters, construct a predictive model, and visualize the model as a nomogram. Receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were used to evaluate prediction performance and clinical utility.
    RESULTS: Precisely 118 patients with DCB and 87 with NDCB in NSCLC received postoperative adjuvant chemotherapy. TIMT was statistically different between the DCB and NDCB groups (P < 0.05). Clinical characteristics (neuron-specific enolase, squamous cell carcinoma antigen, Ki-76, and cM stage) and conventional CT signs (spiculation, bubble-like lucency, pleural retraction, maximum diameter, and CT value of the venous phase) varied between the four TIMT groups (P < 0.05). Furthermore, clinical characteristics (lymphocyte count [LYMPH] and cM stage) and conventional CT signs (bubble-like lucency and Pleural effusion) differed between the DCB and NDCB groups (P < 0.05). Multivariate analysis revealed that TIMT, cM stage, LYMPH, and pleural effusion were independently associated with DCB and were used to construct a nomogram. The area under the curve (AUC) of the combined model was 0.70 (95%CI: 0.64-0.76), with sensitivity and specificity of 0.73 and 0.60, respectively.
    CONCLUSIONS: Conventional CT signs and the TIMT offer a promising approach to predicting clinical outcomes for patients treated with postoperative adjuvant chemotherapy in NSCLC.
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  • 文章类型: Journal Article
    目的:本研究的目的是研究单侧和双侧冠状颅前突(FOA)手术后颅骨生长的纵向变化。
    方法:这项回顾性研究分析了术前(T0)头围(HC)和CT数据,术后即刻(T1),40例患者(23例女性,17名男性),在1987年至2018年之间使用开放方法或牵引成骨(DO)进行了FOA。平均随访期为90.62个月。HC的z分数,基于CT的颅内容积,前后径(APD),双顶直径(BPD),和颅骨高度(CH)使用性别和年龄特异性标准进行计算。进行Logistic回归分析。
    结果:虽然HC的z分数,颅内容积,BPD保持在正常范围内,APD的z评分在-2和-1之间波动,CH的z评分>2,表明从T0到T2与常模相比显著升高.手术年龄显著影响HC的z评分,BPD,和CH在T2(所有p<0.05)。手术时机的延迟与从T1到T2的BPD和CHz评分增加相关(分别为p=0.007和0.019)。FOA的DO导致T2时HCz评分升高,从T0到T1APD增加,然后从T1到T2APD复发。
    结论:这些研究结果表明,延迟手术时机可能支持更好的颅骨生长,如长期随访中HC增加所示。然而,延迟的时机也与异常升高的CH恶化有关。尽管立即APD扩张和长期HC随着DO增加,潜在的复发值得谨慎。虽然建议故意过度校正APD,仔细考虑手术时机和计划至关重要。
    OBJECTIVE: The objective of this study was to investigate the longitudinal changes in cranial growth following fronto-orbital advancement (FOA) surgery in patients with unilateral and bilateral coronal craniosynostosis.
    METHODS: This retrospective review analyzed head circumference (HC) and CT data during preoperative (T0), immediate postoperative (T1), and final follow-up (T2) visits in 40 patients (23 female, 17 male) who underwent FOA using either the open approach or distraction osteogenesis (DO) between 1987 and 2018. The mean follow-up period was 90.62 months. The z-scores of HC, CT-based intracranial volume, anteroposterior diameter (APD), biparietal diameter (BPD), and cranial height (CH) were calculated using sex- and age-specific standards. Logistic regression analysis was performed.
    RESULTS: While the z-scores of HC, intracranial volume, and BPD remained within the normal range, the z-scores of APD fluctuated between -2 and -1, and the z-scores of CH were > 2, indicating a substantial elevation compared with norms from T0 to T2. Age at surgery significantly influenced the z-scores of HC, BPD, and CH at T2 (all p < 0.05). Delayed surgical timing was correlated with increased BPD and CH z-scores from T1 to T2 (p = 0.007 and 0.019, respectively). The DO for FOA resulted in elevated HC z-scores at T2 and increased APD from T0 to T1, followed by a significant APD relapse from T1 to T2.
    CONCLUSIONS: These findings suggest that delayed surgical timing may support better cranial growth, as indicated by increased HC at long-term follow-up. However, delayed timing is also associated with worsening abnormally elevated CH. Despite the immediate APD expansion and long-term HC increase with DO, potential relapse warrants caution. While intentional overcorrection of APD is recommended, careful consideration of surgical timing and planning is essential.
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