Tomography

体层摄影术
  • 文章类型: Journal Article
    Although kidney transplantation is the best therapeutic option for patients with chronic kidney disease, the immunosuppression required greatly increases susceptibility to infections that are responsible for high post-transplant mortality. Pulmonary tuberculosis (TB) represents a major cause of such infections, and its early diagnosis is therefore quite important. In view of that, we researched the manifestations of active pulmonary TB in kidney transplant recipients, through chest X-ray and computed tomography (CT), as well as determining the number of cases of active pulmonary TB occurring over a 3.5-year period at our institution. We identified four cases of active pulmonary TB in kidney transplant recipients. The CT scans provided information complementary to the chest X-ray findings in all four of those cases. We compared our CT findings with those reported in the literature. We analyzed our experience in conjunction with an extensive review of the literature that was nevertheless limited because few studies have been carried out in lowand middle-income countries, where the incidence of TB is higher.
    Apesar de o transplante renal ser a melhor opção terapêutica para pacientes com doença renal crônica, a imunodepressão decorrente desse tratamento eleva muito a suscetibilidade desses pacientes a infecções, responsáveis por altas taxas de mortalidade pós-operatórias. A tuberculose (TB) pulmonar é uma significativa causa dessas infecções, sendo muito importante o seu diagnóstico precoce. Assim, nós pesquisamos as manifestações da TB pulmonar ativa nessa população de transplantados renais por meio de radiografias simples e tomografia computadorizada (TC) do tórax, também para estabelecer o número de casos de TB pulmonar ativa em nossa instituição após levantamento de 3,5 anos. Encontramos quatro casos de TB pulmonar ativa em pacientes transplantados renais. A TC forneceu informações adicionais em relação às radiografias de tórax em 100% dos casos analisados. Comparamos os nossos achados de TC com os relatados na literatura. Somamos a experiência obtida com extensa revisão da literatura, ainda limitada nessa questão, com poucos estudos realizados em países em desenvolvimento onde a incidência de TB é maior.
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  • 文章类型: Journal Article
    一些研究已经评估了蝶鞍(ST)的正常性参数,这对于面对可能影响这种结构的不同颅面综合征很重要。因此,这项研究总结了关于ST在非综合征个体性别估计中的作用的科学证据.研究方案已注册(前瞻性国际注册系统审查#CRD42021256469),然后在六个数据库中进行电子搜索(PubMed,LILACS,WebofScience,Scopus,EMBASE,和LIVIVO)和灰色文学(谷歌学者和OpenGrey)。线性元分析(宽度,长度,高度,和直径)和体积测量,除了对偏见风险(RoB)和证据确定性的评估之外,被执行了。经过986篇文章的筛选,13人通过荟萃分析进行了评估(男性1307人,女性1231人)。在亚组分析中,女性的宽度值较低(横向X光片;-0.67mm;P=0.040),长度(计算机断层扫描;-0.23mm;P=0.020),与男性相比,直径(计算机断层扫描;-0.27mm;P<0.001)。身高差异无统计学意义(P=0.95),面积(P=0.72),和体积(P=0.21)。大多数研究显示适度的RoB,结果证据的确定性非常低。在这次审查中,在ST的长度和直径方面,性别之间存在显着差异;但是,必须考虑研究的异质性。
    来自不同地理区域的研究根据性别评估了ST的形态,并将这种解剖结构作为二态性的重要指标。Meta分析显示女性ST长度和直径较短。亚组分析发现,根据侧颅X光片,女性的ST宽度较低。亚组分析根据CT扫描发现女性的长度和直径较小。
    Several studies have evaluated the parameters of normality of the sella turcica (ST), which is important to face different craniofacial syndromes that may affect this structure. Therefore, this research summarized the scientific evidence on the role of ST in the sex estimation of non-syndromic individuals. The research protocol was registered (Prospective International Registry of Systematic Reviews # CRD42021256469), followed by an electronic search in six databases (PubMed, LILACS, Web of Science, Scopus, EMBASE, and LIVIVO) and gray literature (Google Scholar and OpenGrey). Meta-analysis of linear (width, length, height, and diameter) and volumetric measurements, in addition to an assessment of risk of bias (RoB) and certainty of evidence, were performed. After the screening of 986 articles, 13 were evaluated by meta-analysis (1 307 males and 1 231 females). In subgroup analysis, females had lower values for width (lateral radiograph; -0.67 mm; P = 0.040), length (computed tomography; -0.23 mm; P = 0.020), and diameter (computed tomography; -0.27 mm; P < 0.001) compared to males. There was no statistically significant difference regarding height (P = 0.95), area (P = 0.72), and volume (P = 0.21). Most studies exhibited moderate RoB, and the certainty of evidence of the outcomes was very low. In this review, significant differences were observed between the sexes for the length and diameter of the ST; however, the heterogeneity of the studies must be considered.
    UNASSIGNED: Studies from different geographic regions evaluated the morphology of ST according to sex and showed this anatomical structure as an important indicator of dimorphism.Meta-analysis showed shorter ST length and diameter in women.Subgroup analysis found lower ST width in women based on lateral skull radiographs.Subgroup analysis found smaller lengths and diameters in women based on CT scans.
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  • 文章类型: Journal Article
    随着人们对使用结构木材的兴趣迅速增长,需要使用无损检测(NDT)检查和评估这些结构。这篇综述文章总结了木材检测的无损检测方法。在概述了当前使用的最重要的NDT方法之后,详细介绍了探地雷达(GPR)和超声波检测(UST)。这两种技术可以在原位应用,并为定量评估和损伤检测产生有用的视觉表示。凭借其商业可用性和便携性,GPR可以帮助快速识别关键特征,如水分,空隙,和木结构中的金属连接器。UST,它能有效地检测深层裂缝,分层,以及与水分含量有关的超声波速度变化,补充GPR的能力。这两种技术的非破坏性保留了木材的结构完整性,在不损害完整性和耐久性的情况下进行全面评估。诸如合成孔径聚焦技术(SAFT)和全聚焦方法(TFM)之类的技术允许重建检查员可以容易地解释的图像以进行定量评估。新型传感器的发展,仪器,和分析技术继续改善GPR和UST在木材上的应用。然而,由于这种复杂材料的均匀各向异性,仍然存在挑战,以量化缺陷和表征夹杂物可靠和准确。通过整合考虑材料复杂属性的先进成像算法,将测量与模拟相结合,并采用机器学习技术,可以进一步推进GPR和UST成像以及木结构损伤检测的实施和应用。
    With the rapidly growing interest in using structural timber, a need exists to inspect and assess these structures using non-destructive testing (NDT). This review article summarizes NDT methods for wood inspection. After an overview of the most important NDT methods currently used, a detailed review of Ground Penetrating Radar (GPR) and Ultrasonic Testing (UST) is presented. These two techniques can be applied in situ and produce useful visual representations for quantitative assessments and damage detection. With its commercial availability and portability, GPR can help rapidly identify critical features such as moisture, voids, and metal connectors in wood structures. UST, which effectively detects deep cracks, delaminations, and variations in ultrasonic wave velocity related to moisture content, complements GPR\'s capabilities. The non-destructive nature of both techniques preserves the structural integrity of timber, enabling thorough assessments without compromising integrity and durability. Techniques such as the Synthetic Aperture Focusing Technique (SAFT) and Total Focusing Method (TFM) allow for reconstructing images that an inspector can readily interpret for quantitative assessment. The development of new sensors, instruments, and analysis techniques has continued to improve the application of GPR and UST on wood. However, due to the hon-homogeneous anisotropic properties of this complex material, challenges remain to quantify defects and characterize inclusions reliably and accurately. By integrating advanced imaging algorithms that consider the material\'s complex properties, combining measurements with simulations, and employing machine learning techniques, the implementation and application of GPR and UST imaging and damage detection for wood structures can be further advanced.
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  • 文章类型: Journal Article
    黄斑营养不良(MD)构成了导致明显视力损害的遗传性视网膜疾病的集合,主要是由于进行性黄斑萎缩。这些情况的特征在于黄斑中的双侧和相对对称的异常,这些异常显着损害了中枢视觉功能。眼底成像的最新进展,尤其是光学相干断层扫描(OCT),增强了我们对MD的理解和诊断能力。OCT能够在眼底检查中出现可见的黄斑病变之前,识别神经感觉视网膜紊乱模式以及对营养不良中的视网膜色素上皮(RPE)和感光细胞的损伤程度。它不仅可以帮助我们诊断视网膜和脉络膜病变,还可以指导我们监测疾病的进展,分期,以及对治疗的反应。在这次审查中,我们总结了OCT在一些最常见MD中的关键发现。
    Macular dystrophies (MDs) constitute a collection of hereditary retina disorders leading to notable visual impairment, primarily due to progressive macular atrophy. These conditions are distinguished by bilateral and relatively symmetrical abnormalities in the macula that significantly impair central visual function. Recent strides in fundus imaging, especially optical coherence tomography (OCT), have enhanced our comprehension and diagnostic capabilities for MD. OCT enables the identification of neurosensory retinal disorganization patterns and the extent of damage to retinal pigment epithelium (RPE) and photoreceptor cells in the dystrophies before visible macular pathology appears on fundus examinations. It not only helps us in diagnostic retinal and choroidal pathologies but also guides us in monitoring the progression of, staging of, and response to treatment. In this review, we summarize the key findings on OCT in some of the most common MD.
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  • 文章类型: Journal Article
    感染性心内膜炎(IE)以发热为特征,心脏杂音,和栓子。脾栓塞在左侧IE中常见。对2000年至2023年之间发表的有关脾栓塞(SE)的文献进行了系统回顾。电子数据库中的搜索策略确定了2000年1月1日至2023年10月4日之间发表的2751项研究,其中29项最终被包括在内。结果表明,主要用于检测栓塞的影像学检查是计算机断层扫描(CT),磁共振成像,正电子发射断层扫描(PET)/CT,单光子发射计算机断层扫描/CT,超声,和超声造影.最近的研究通常使用18F-FDGPET-CT。SE的比例为1.4%至71.7%。只有7项研究进行了系统的常规CT筛查腹内栓塞,SE的加权平均频率为22%(范围:8-34.8%)。18F-FDGPET-CT在7项研究中进行了系统的研究,脾摄取量的加权平均值为4.5%。关于脾栓塞的频率和处理,已发表的文献缺乏统一性。CT扫描是最常用的方法,直到最近,18F-FDGPET-CT扫描开始占主导地位。关于SE频率的更多数据是必要的,特别是关注它们对IE管理和预后的影响。
    Infective endocarditis (IE) is characterised by fever, heart murmurs, and emboli. Splenic emboli are frequent in left-sided IE. A systematic review of the literature published on splenic embolism (SE) between 2000 and 2023 was conducted. Search strategies in electronic databases identified 2751 studies published between 1 January 2000 and 4 October 2023, of which 29 were finally included. The results showed that the imaging tests predominantly used to detect embolisms were computed tomography (CT), magnetic resonance imaging, positron emission tomography (PET)/CT, single-photon emission computed tomography/CT, ultrasound, and contrast-enhanced ultrasound. More recent studies typically used 18F-FDG PET-CT. The proportion of SE ranged from 1.4% to 71.7%. Only seven studies performed systematic conventional CT screening for intra-abdominal emboli, and the weighted mean frequency of SE was 22% (range: 8-34.8%). 18F-FDG PET-CT was performed systematically in seven studies, and splenic uptake was found in a weighted mean of 4.5%. There was a lack of uniformity in the published literature regarding the frequency and management of splenic embolisation. CT scans were the most frequently used method, until recently, when 18F-FDG PET-CT scans began to predominate. More data are necessary regarding the frequency of SE, especially focusing on their impact on IE management and prognosis.
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  • 文章类型: Case Reports
    该技术报告说明了通过后路经椎弓根入路在身体和轴(C2椎骨)的腔内进行计算机断层扫描(CT)引导的骨活检的技术,并使用术前对比增强扫描来突出椎动脉的过程。该技术通过两个示例案例介绍:一名患有成骨细胞瘤和继发性动脉瘤性骨囊肿的儿科患者和一名患有黑色素瘤转移的成年患者。这种情况突出了CT引导的后外侧/经椎弓根入路在C2的身体和窝中进行安全有效的活检的潜力,即使在儿科患者中也是如此。
    This technical report illustrates the technique to perform computed tomography (CT)-guided bone biopsies in the body and dens of the axis (C2 vertebra) through a posterior transpedicular approach with the use of preoperative contrast-enhanced scans to highlight the course of the vertebral artery. The technique is presented through two exemplification cases: a pediatric patient with osteoblastoma and secondary aneurysmal bone cyst and one adult patient with melanoma metastasis. This case highlights the potential of the CT-guided posterolateral/transpedicular approach for performing safe and effective biopsies in the body and dens of C2, even in pediatric patients.
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  • 文章类型: Journal Article
    电阻抗断层扫描(EIT)是一种新颖的实时肺部成像技术,用于个性化通气调整,表明有希望的结果在动物和人类。本研究旨在评估其与传统方案相比改善通气和氧合的临床实用性。全面的电子数据库筛选工作一直持续到11月30日,2023年。随机对照试验,对照临床试验,比较队列研究,并评估EIT指导的PEEP滴定和成人ARDS患者的常规方法的结果,通气参数,包括P/F比。我们检索了五项对照队列研究和两项RCT,其中515例患者总体死亡率降低[RR=0.68;95%CI:0.49至0.95;I2=0%],动态依从性更好[MD=3.46;95%CI:1.59~5.34;I2=0%],PaO2/FiO2比值无显著差异[MD=6.5;95CI-13.86~26.76;I2=74%]。除PaO2/FiO2外,所需的信息大小以死亡率降低50%为基础,达到95%的功率。10%的改善依从性,因为所述结果的累积Z得分越过了α支出边界,并且没有下降到无用的内部楔形以下。EIT指导的个性化PEEP滴定是一种新颖的方式;需要进一步精心设计的研究来证实其实用性。
    Electrical Impedance Tomography (EIT) is a novel real-time lung imaging technology for personalized ventilation adjustments, indicating promising results in animals and humans. The present study aimed to assess its clinical utility for improved ventilation and oxygenation compared to traditional protocols. Comprehensive electronic database screening was done until 30th November, 2023. Randomized controlled trials, controlled clinical trials, comparative cohort studies, and assessments of EIT-guided PEEP titration and conventional methods in adult ARDS patients regarding outcome, ventilatory parameters, and P/F ratio were included. Our search retrieved five controlled cohort studies and two RCTs with 515 patients and overall reduced risk of mortality [RR = 0.68; 95% CI: 0.49 to 0.95; I2 = 0%], better dynamic compliance [MD = 3.46; 95% CI: 1.59 to 5.34; I2 = 0%] with no significant difference in PaO2/FiO2 ratio [MD = 6.5; 95%CI -13.86 to 26.76; I2 = 74%]. The required information size except PaO2/FiO2 was achieved for a power of 95% based on the 50% reduction in risk of mortality, 10% improved compliance as the cumulative Z-score of the said outcomes crossed the alpha spending boundary and did not dip below the inner wedge of futility. EIT-guided individualized PEEP titration is a novel modality; further well-designed studies are needed to substantiate its utility.
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  • 文章类型: Systematic Review
    目的:评估电阻抗断层扫描(EIT)在优化急性呼吸窘迫综合征(ARDS)患者呼气末正压(PEEP)以增强呼吸系统力学并预防呼吸机相关性肺损伤(VILI)中的功效。与传统方法相比。
    方法:我们进行了系统综述和荟萃分析,2012年1月至2023年5月的文学,来自Scopus,PubMed,MEDLINE(Ovid),科克伦,和LILACS,与传统方法相比,评估了EIT指导的PEEP策略在ARDS中的应用。13项研究(3项随机,使用随机效应模型对涉及623例ARDS患者的主要结局(呼吸力学和机械动力)和次要结局(PaO2/FiO2比,死亡率,住在重症监护病房(ICU),无呼吸机日)。
    结果:EIT引导的PEEP显着改善了肺顺应性(n=941例,平均差(MD)=4.33,95%置信区间(CI)[2.94,5.71]),降低的机械功率(n=148,MD=-1.99,95%CI[-3.51,-0.47]),与传统方法相比,驱动压力降低(n=903,MD=-1.20,95%CI[-2.33,-0.07])。敏感性分析显示,在随机临床试验中,EIT引导的PEEP对肺顺应性的积极作用与非随机研究汇总(MD)=2.43(95%CI-0.39至5.26),表明有改善的趋势。死亡率降低(259名患者,在三项研究中,相对危险度(RR)=0.64,95%CI[0.45,0.91])与依从性和驱动压力的适度改善相关.
    结论:EIT促进实时,个性化PEEP调整,改善呼吸系统力学。整合EIT作为机械通气的指导工具在预防呼吸机引起的肺损伤方面具有潜在的益处。大规模研究对于验证和优化EIT在ARDS管理中的临床应用至关重要。
    OBJECTIVE: Assessing efficacy of electrical impedance tomography (EIT) in optimizing positive end-expiratory pressure (PEEP) for acute respiratory distress syndrome (ARDS) patients to enhance respiratory system mechanics and prevent ventilator-induced lung injury (VILI), compared to traditional methods.
    METHODS: We carried out a systematic review and meta-analysis, spanning literature from January 2012 to May 2023, sourced from Scopus, PubMed, MEDLINE (Ovid), Cochrane, and LILACS, evaluated EIT-guided PEEP strategies in ARDS versus conventional methods. Thirteen studies (3 randomized, 10 non-randomized) involving 623 ARDS patients were analyzed using random-effects models for primary outcomes (respiratory mechanics and mechanical power) and secondary outcomes (PaO2/FiO2 ratio, mortality, stays in intensive care unit (ICU), ventilator-free days).
    RESULTS: EIT-guided PEEP significantly improved lung compliance (n = 941 cases, mean difference (MD) = 4.33, 95% confidence interval (CI) [2.94, 5.71]), reduced mechanical power (n = 148, MD = - 1.99, 95% CI [- 3.51, - 0.47]), and lowered driving pressure (n = 903, MD = - 1.20, 95% CI [- 2.33, - 0.07]) compared to traditional methods. Sensitivity analysis showed consistent positive effect of EIT-guided PEEP on lung compliance in randomized clinical trials vs. non-randomized studies pooled (MD) = 2.43 (95% CI - 0.39 to 5.26), indicating a trend towards improvement. A reduction in mortality rate (259 patients, relative risk (RR) = 0.64, 95% CI [0.45, 0.91]) was associated with modest improvements in compliance and driving pressure in three studies.
    CONCLUSIONS: EIT facilitates real-time, individualized PEEP adjustments, improving respiratory system mechanics. Integration of EIT as a guiding tool in mechanical ventilation holds potential benefits in preventing ventilator-induced lung injury. Larger-scale studies are essential to validate and optimize EIT\'s clinical utility in ARDS management.
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  • 文章类型: Journal Article
    目的:左心室机械不同步(LVMD)是冠心病的重要预后因素。越来越多的证据表明,从门控心肌SPECT的相位分析得出的LVMD参数可能允许对未来的心脏事件进行风险分层。我们对冠心病患者门控SPECT的LVMD预后价值进行了系统评价和荟萃分析。
    方法:PubMed,Embase,并在2022年8月25日之前搜索Cochrane文库,研究报告门控SPECT对全因死亡结局的LVMD的预后价值,心脏死亡,或冠状动脉疾病患者的主要不良心血管事件(MACE)。使用随机效应模型对危险比(HR)及其95%置信区间(CI)进行荟萃分析。
    结果:9项研究(26,750名患者)纳入了定性综合。在各种研究中使用的SPECTLVMD参数中,高相位标准偏差,相位带宽,和相位熵被广泛评估,据报道与全因死亡率高有关,心脏死亡,或MACE。对于定量综合中的五项研究(23,973名患者),预测MACE的LVMD合并HR为2.81(95%CI2.03-3.88).使用组合相位参数来定义LVMD的研究显示出比使用相位熵的研究更高的HR(p=0.0180)。
    结论:门控心肌SPECT的LVMD是冠状动脉疾病的重要预后因素。门控SPECT的相位分析可用于准确的风险分层,并可用于此类患者的临床决策。
    OBJECTIVE: Left ventricular mechanical dyssynchrony (LVMD) is an important prognostic factor in coronary artery disease. A growing body of evidence indicates that LVMD parameters derived from phase analysis of gated myocardial SPECT may allow risk stratification for future cardiac events. We performed a systematic review and meta-analysis on the prognostic value of LVMD on gated SPECT in patients with coronary artery disease.
    METHODS: PubMed, Embase, and the Cochrane library were searched until August 25, 2022, for studies reporting the prognostic value of LVMD on gated SPECT for outcomes of all-cause death, cardiac death, or major adverse cardiovascular event (MACE) in patients with coronary artery disease. Hazard ratios (HRs) and their 95% confidence intervals (CIs) were meta-analytically pooled using a random-effects model.
    RESULTS: Nine studies (26,750 patients) were included in a qualitative synthesis. Among the SPECT LVMD parameters used in various studies, high phase standard deviation, phase bandwidth, and phase entropy were widely evaluated and reported to be associated with high rates of all-cause death, cardiac death, or MACE. For five studies (23,973 patients) in the quantitative synthesis, the pooled HR of LVMD for predicting MACE was 2.81 (95% CI 2.03-3.88). Studies using combined phase parameters to define LVMD showed higher HRs than a study using phase entropy (p = 0.0180).
    CONCLUSIONS: LVMD from gated myocardial SPECT is a significant prognostic factor for coronary artery disease. Phase analysis of gated SPECT may be useful for accurate risk stratification and could be applied for clinical decision-making in such patients.
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  • 文章类型: Journal Article
    电阻抗断层成像(EIT)是一种新的无创机械通气监测方法,在床边,对危重病人有用。它允许肺部监测通气和灌注,获取提供肺功能信息的图像。它基于阻抗测量法的物理原理或人体传导电流的能力。各种研究表明,它在成人和儿科呼吸窘迫综合征中都很有用,肺炎和肺不张除了肺血栓栓塞和肺动脉高压还提供肺灌注信息,并且可能在围手术期医学中非常有用;特别是在儿科中,避免使用电离辐射进行重复的影像学检查。
    Electrical impedance tomography (EIT) is a new method of monitoring non-invasive mechanical ventilation, at the bedside and useful in critically ill patients. It allows lung monitoring of ventilation and perfusion, obtaining images that provide information on lung function. It is based on the physical principle of impedanciometry or the body\'s ability to conduct an electrical current. Various studies have shown its usefulness both in adults and in pediatrics in respiratory distress syndrome, pneumonia and atelectasis in addition to pulmonary thromboembolism and pulmonary hypertension by also providing information on pulmonary perfusion, and may be very useful in perioperative medicine; especially in pediatrics avoiding repetitive imaging tests with ionizing radiation.
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