computer tomography

计算机断层扫描
  • 文章类型: Journal Article
    医学成像幻影(MIP)校准成像设备,培训医疗专业人员,可以帮助程序规划。传统MIP成本高且定制有限。增材制造允许可定制,患者特有的幻影。这项研究检查了可注射对比剂的CT衰减特性,有腔的3D打印体模,以优化组织模拟能力。MIP是由髂分叉附近复杂骨盆肿瘤的CT构建的。这些由三个腔室组成的结构的三维重建(主动脉,下腔静脉,肿瘤)带有造影剂注射端口的3D打印。所需的衰减为200HU(动脉I),150HU(静脉I),40HU(肿瘤I),150HU(动脉II),90HU(静脉II),和400HU(肿瘤II)。注射了Optiray350和水的溶液,然后在CT上扫描了体模.使用ROI测量衰减。六个阶段的平均衰减如下:肿瘤I的37.49HU,200.50HU用于静脉I,227.92HU用于动脉I,326.20HU用于肿瘤II,91.32HU用于静脉II,和132.08HU用于动脉II。尽管观察到的衰减和目标衰减之间的百分比差异很大,观察到的各相之间的相对HU差异与目标HU差异相似.观察到的衰减反映了所用对比溶液的相对浓度,与对比浓度表现出强正相关。造影剂可注射的肿瘤体模表现出有用的生理衰减值范围,即使在制造过程之后,也能够修改组织模仿3D打印的体模。
    Medical Imaging Phantoms (MIPs) calibrate imaging devices, train medical professionals, and can help procedural planning. Traditional MIPs are costly and limited in customization. Additive manufacturing allows for customizable, patient-specific phantoms. This study examines the CT attenuation characteristics of contrast-injectable, chambered 3D-printed phantoms to optimize tissue-mimicking capabilities. A MIP was constructed from a CT of a complex pelvic tumor near the iliac bifurcation. A 3D reconstruction of these structures composed of three chambers (aorta, inferior vena cava, tumor) with ports for contrast injection was 3D printed. Desired attenuations were 200 HU (arterial I), 150 HU (venous I), 40 HU (tumor I), 150 HU (arterial II), 90 HU (venous II), and 400 HU (tumor II). Solutions of Optiray 350 and water were injected, and the phantom was scanned on CT. Attenuations were measured using ROIs. Mean attenuation for the six phases was as follows: 37.49 HU for tumor I, 200.50 HU for venous I, 227.92 HU for arterial I, 326.20 HU for tumor II, 91.32 HU for venous II, and 132.08 HU for arterial II. Although the percent differences between observed and goal attenuation were high, the observed relative HU differences between phases were similar to goal HU differences. The observed attenuations reflected the relative concentrations of contrast solutions used, exhibiting a strong positive correlation with contrast concentration. The contrast-injectable tumor phantom exhibited a useful physiologic range of attenuation values, enabling the modification of tissue-mimicking 3D-printed phantoms even after the manufacturing process.
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  • 文章类型: Journal Article
    背景:几丁质酶-3样蛋白-1(CHI3L1)是哺乳动物几丁质酶样蛋白中的一员,血清CHI3L1水平升高与肝细胞癌(HCC)预后不良相关。本研究旨在探讨肝移植(LT)后肝癌患者血清CHI3L1水平与身体成分参数之间的关系。
    方法:这项回顾性研究纳入了200例肝癌LT术后患者。收集血样,通过酶联免疫吸附试验测量CHI3L1的血清浓度。计算机断层扫描(CT)用于估计骨骼肌和脂肪组织质量。进行Spearman等级相关检验以评估血清CHI3L1水平与这些身体成分参数之间的关联。采用Cox比例风险回归模型来确定独立的预后因素。使用Kaplan-Meier方法构建总生存期(OS)和无复发生存期(RFS)曲线,并通过对数秩检验进行比较。
    结果:根据骨骼肌辐射衰减(SMRA),共有71例患者(35.5%)被诊断为肌萎缩。非肌骨形成组5年OS率为66.9%,显著高于肌骨形成组的49.5%(p=0.025),而肌骨化病组(5年RFS:52.6%)或非肌骨化病组(5年RFS:42.0%)的RFS没有显着差异(p=0.068)。血清CHI3L1水平与SMRA呈显著负相关(r=-0.3,p<0.001)。有趣的是,在患有肌骨沉着症的患者中,Kaplan-Meier分析显示,血清CHI3L1水平升高与OS(p<0.001)和RFS(p=0.047)较差相关。然而,在没有肌肉骨化的患者中,Kaplan-Meier分析发现血清CHI3L1水平升高与OS(p=0.070)或RFS(p=0.104)无关。
    结论:CHI3L1升高与SMRA呈负相关,并预测中国人群肝癌肝移植后预后较差,尤其是那些伴有肌骨形成的患者。监测血清CHI3L1可预测预后,有效指导个体化营养干预。
    BACKGROUND: Chitinase-3 like-protein-1 (CHI3L1) is a member of the mammalian chitinase-like proteins and elevated serum CHI3L1 level has been proved to be associated with poor prognosis in hepatocellular carcinoma (HCC). This study aimed to investigate the relationship between serum CHI3L1 levels and body composition parameters in patients with HCC after liver transplantation (LT).
    METHODS: This retrospective study enrolled 200 patients after LT for HCC. Blood samples were collected and serum concentrations of CHI3L1 were measured by enzyme-linked immunosorbent assay. Computer tomography (CT) were used to estimate skeletal muscle and adipose tissue mass. Spearman\'s rank correlation test was performed to assess associations between serum CHI3L1 levels and these body composition parameters. A Cox proportional-hazards regression model was performed to identify independent prognostic factors. Overall survival (OS) and recurrence-free survival (RFS) curves were constructed using the Kaplan-Meier method and compared by the log-rank test.
    RESULTS: Total 71 patients (35.5%) were diagnosed with myosteatosis according to skeletal muscle radiation attenuation (SMRA). The 5-year OS rates were 66.9% in non-myosteatosis group, significantly higher than 49.5% in myosteatosis group (p = 0.025), while the RFS of myosteatosis group (5-year RFS: 52.6%) or non-myosteatosis group (5-year RFS: 42.0%) shown no significant difference (p = 0.068). The serum CHI3L1 level were significantly negative correlated with SMRA (r = -0.3, p < 0.001). Interestingly, in patients with myosteatosis, Kaplan-Meier analysis revealed that elevated serum CHI3L1 levels were associated with worse OS (p < 0.001) and RFS (p = 0.047). However, in patients without myosteatosis, Kaplan-Meier analysis found elevated serum CHI3L1 levels were not associated with OS (p = 0.070) or RFS (p = 0.104).
    CONCLUSIONS: Elevated CHI3L1 was negatively correlated with SMRA, and predicted poorer prognosis in Chinese population after LT for HCC, especially in those patients with concomitant myosteatosis. Monitoring serum CHI3L1 can predict prognosis and effectively guide individual nutrition intervention.
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  • 文章类型: Journal Article
    暂无摘要。
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  • 文章类型: Journal Article
    比较断层合成表现与X线摄影术的区别,以区分可疑轴性脊柱关节炎(SpA)患者的骶髂关节正常或退行性变化。
    射线照相术,对疑似SpA的连续患者在同一天进行了骶髂关节的断层合成和CT检查(29例患者)。检查是回顾性独立阅读的,被两名放射科医生(一名初级和一名高级,和初级学生两次)。使用kappa系数评估观察者之间和观察者之间的一致性。每种成像灵敏度的有效剂量,评估了特异性和准确性,并与作为金标准的CT进行了比较.
    CT检测到15/58个关节伴有骶髂关节炎。成像灵敏度,特异性和准确性为60%,84%和44%,分别,射线照相和87%,断层合成分别为91%和77%。断层合成的平均有效剂量显着低于CT(少5倍),而显着高于放射线照相术(多8倍)。
    对于疑似SpA的患者,断层合成优于X线摄影,辐射暴露比CT少5倍。
    UNASSIGNED: To compare tomosynthesis performance to radiography for the differentiation of sacroiliitis versus normal or degenerative changes in sacroiliac joints in patients with suspected axial spondyloarthritis (SpA).
    UNASSIGNED: Radiography, tomosynthesis and CT of sacroiliac joints (29 patients) were performed on the same day in consecutive patients with suspected SpA. The examinations were retrospectively read independently, blinded by two radiologists (one junior and one senior, and twice by one junior). Interobserver and intraobserver agreement was evaluated using the kappa coefficient. Effective doses for each imaging sensitivity, specificity and accuracy were assessed and compared with CT as gold standard.
    UNASSIGNED: CT detected 15/58 joints with sacroiliitis. The imaging sensitivity, specificity and accuracy were 60%, 84% and 44%, respectively, for radiography and 87%, 91% and 77% for tomosynthesis. The mean effective dose for tomosynthesis was significantly lower than that of CT (5-fold less) and significantly higher than that of radiography (8-fold more).
    UNASSIGNED: Tomosynthesis is superior to radiography for sacroiliitis detection in patients with suspected SpA, with 5-fold less radiation exposure than CT.
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  • 文章类型: Journal Article
    反刍动物的脑脓肿通常由原发感染灶引起,导致受影响动物的预后不良。这凸显了对不同反刍动物物种的脑脓肿进行全面研究的必要性。我们回顾性调查了流行病学的医疗记录,临床,神经影像学,解剖学病理学,和六只反刍动物的细菌学发现(三只山羊,两头母牛,和一只羊)被诊断患有脑脓肿。所有研究的动物都是雌性。冷漠(50%)强迫性行走(33%),面部敏感度下降(33%),压头(33%),缉获量(33%),半乳质精神状态(33%),斜视(33%),单侧失明(33%),和盘旋(33%)是最常见的神经系统症状。白细胞增多和中性粒细胞增多是血液学评估的主要发现。脑脊液(CSF)分析显示主要是高蛋白质和细胞增多症。在三种情况下,使用计算机断层扫描或磁共振成像,能够识别典型的脓肿病变,随后在验尸中得到证实。在大多数情况下,脓肿样品和/或CSF的微生物培养物显示细菌共感染。先进的影像学检查,结合CSF分析,可以帮助诊断,尽管确认通常依赖于死后评估和病原体的隔离。这项研究有助于临床病理方面,神经影像,和家养反刍动物脑脓肿的细菌学诊断。
    Brain abscesses in ruminants often arise from primary infection foci, leading to an unfavorable prognosis for affected animals. This highlights the need for comprehensive studies on brain abscesses across different ruminant species. We retrospectively investigated medical records of epidemiological, clinical, neuroimaging, anatomopathological, and bacteriological findings in six ruminants (three goats, two cows, and one sheep) diagnosed with brain abscesses. All animals studied were female. Apathy (50%), compulsive walking (33%), decreased facial sensitivity (33%), head pressing (33%), seizures (33%), semicomatous mental status (33%), strabismus (33%), unilateral blindness (33%), and circling (33%) represented the most common neurologic signs. Leukocytosis and neutrophilia were the main findings in the hematological evaluation. Cerebrospinal fluid (CSF) analysis revealed predominant hyperproteinorrachia and pleocytosis. In three cases, computed tomography or magnetic resonance imaging were used, enabling the identification of typical abscess lesions, which were subsequently confirmed during postmortem examination. Microbiological culture of the abscess samples and/or CSF revealed bacterial coinfections in most cases. Advanced imaging examinations, combined with CSF analysis, can aid in diagnosis, although confirmation typically relies on postmortem evaluation and isolation of the causative agent. This study contributes to clinicopathological aspects, neuroimages, and bacteriological diagnosis of brain abscesses in domestic ruminants.
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  • 文章类型: Journal Article
    背景:孤立性肺结节的诊断一直是临床研究的难点和重点。尤其是肉芽肿结节(GNs)与分叶和针状征象,容易误诊为恶性肿瘤。因此,在这项研究中,我们利用CT深度学习(DL)模型来区分具有分叶和针状征象的GNs与实性肺腺癌(LADCs),提高术前诊断的准确性。
    方法:对来自3家医疗机构的420例经病理证实的GNs和LADCs患者进行回顾性研究。识别并标记非增强CT(NECT)和静脉对比增强CT(VECT)中的感兴趣区域,并构建了自我监督标签。来自机构1的病例被随机分为训练集(TS)和内部验证集(IVS),来自机构2和3的病例被视为外部验证集(EVS)。使用自监督迁移学习进行训练和验证,并将结果与放射科医生的诊断结果进行比较。
    结果:DL模型在区分GNs和LADC方面取得了良好的性能,IVS中的曲线下面积(AUC)值为0.917、0.876和0.896,NECT中的EVS为0.889、0.879和0.881,VECT,静脉造影增强CT(NEVECT)图像未增强,分别。放射科医生1、2、3和4的AUC为,分别,(IVS)中的0.739、0.783、0.883和0.901,以及EVS中的0.760、0.760、0.841和0.844。
    结论:CTDL模型对术前从实体LADC中分化出具有分叶和毛刺征象的GNs具有重要价值,其预测性能高于放射科医师。
    BACKGROUND: The diagnosis of solitary pulmonary nodules has always been a difficult and important point in clinical research, especially granulomatous nodules (GNs) with lobulation and spiculation signs, which are easily misdiagnosed as malignant tumors. Therefore, in this study, we utilised a CT deep learning (DL) model to distinguish GNs with lobulation and spiculation signs from solid lung adenocarcinomas (LADCs), to improve the diagnostic accuracy of preoperative diagnosis.
    METHODS: 420 patients with pathologically confirmed GNs and LADCs from three medical institutions were retrospectively enrolled. The regions of interest in non-enhanced CT (NECT) and venous contrast-enhanced CT (VECT) were identified and labeled, and self-supervised labels were constructed. Cases from institution 1 were randomly divided into a training set (TS) and an internal validation set (IVS), and cases from institutions 2 and 3 were treated as an external validation set (EVS). Training and validation were performed using self-supervised transfer learning, and the results were compared with the radiologists\' diagnoses.
    RESULTS: The DL model achieved good performance in distinguishing GNs and LADCs, with area under curve (AUC) values of 0.917, 0.876, and 0.896 in the IVS and 0.889, 0.879, and 0.881 in the EVS for NECT, VECT, and non-enhanced with venous contrast-enhanced CT (NEVECT) images, respectively. The AUCs of radiologists 1, 2, 3, and 4 were, respectively, 0.739, 0.783, 0.883, and 0.901 in the (IVS) and 0.760, 0.760, 0.841, and 0.844 in the EVS.
    CONCLUSIONS: A CT DL model showed great value for preoperative differentiation of GNs with lobulation and spiculation signs from solid LADCs, and its predictive performance was higher than that of radiologists.
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  • 文章类型: Journal Article
    确定评估食管鳞状细胞癌(ESCC)预后最敏感的影像学检查方法。
    30例食管鳞状细胞癌(ESCC)患者参加了研究并接受了放化疗(CRT)。根据生存状态将其分为两组:生存组和非生存组。诊断测试用于确定评估预后的最有效的影像学检查方法。
    1.两组之间在指定时间点的食管造影或计算机断层扫描(CT)上显示的肿瘤长度或CT上显示的最大食管壁厚度没有显着差异。2.在第6周治疗结束时,生存组扩散加权成像(DWI)的肿瘤长度明显低于非生存组(P=0.001)。ROC曲线下面积为0.840(P=0.002),诊断效率中等准确。3.生存组的表观扩散系数(ADC)值在治疗第4周和第6周显著高于非生存组(均P<0.001)。曲线下面积分别为0.866和0.970,P值分别为0.001和<0.001,诊断准确率较好。Cox回归分析显示治疗第6周末的ADC是独立的危险因素。
    与食管造影和CT相比,DW-MRI在预测ESCC预后方面具有一定优势。
    UNASSIGNED: To identify the most sensitive imaging examination method to evaluate the prognosis of esophageal squamous cell carcinoma (ESCC).
    UNASSIGNED: Thirty patients with esophageal squamous cell carcinoma (ESCC) participated in the study and underwent chemoradiotherapy (CRT). They were divided into two groups based on their survival status: the survival group and non-survival group. The diagnostic tests were utilized to determine the most effective imaging examination method for assessing the prognosis.
    UNASSIGNED: 1. There were no significant differences in tumor length shown on esophagography or computed tomography (CT) or the maximal esophageal wall thickness shown on CT at the specified time points between the two groups. 2. The tumor length on diffusion-weighted imaging (DWI) in the survival group was significantly lower than in the non-survival group at the end of the sixth week of treatment (P=0.001). The area under the ROC curve was 0.840 (P=0.002), and the diagnostic efficiency was moderately accurate. 3. The apparent diffusion coefficient (ADC) values of the survival group were significantly higher than those in the non-survival group at the end of the fourth week and sixth week of treatment (both P<0.001). Areas under the curve were 0.866 and 0.970, with P values of 0.001 and <0.001 and good diagnostic accuracy. Cox regression analyses indicated the ADC at the end of the sixth week of treatment was an independent risk factor.
    UNASSIGNED: Compared with esophagography and CT, DW-MRI has certain advantages in predicting the prognosis of ESCC.
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  • 文章类型: Case Reports
    Omental梗塞是急性腹痛的罕见原因,通常是良性的和自我限制的。梗死的意义在于它可以模仿其他腹部病变,包括阑尾炎,胆囊炎,胰腺炎,或反流病。诊断性腹腔镜检查提供了大网膜梗塞的明确诊断,但它是侵入性的,由于资源有限。当需要非侵入性诊断方法时,腹部和骨盆的计算机断层扫描被认为是诊断网膜梗塞的金标准。此外,超声也可以用于儿童。目前,对影像学证实的网膜梗死患者的诊断和治疗尚无共识.外科医生和放射科医生必须将自发性梗塞网膜视为急性腹痛的罕见原因,因为患者可以通过保守或手术方法获得良好的结果。然而,只有在不可能有替代病理的稳定患者中,才应考虑保守治疗.
    Omental infarction is a rare cause of acute abdominal pain, often benign and self-limiting. The significance of infarction lies in the fact that it can mimic other abdominal pathologies including appendicitis, cholecystitis, pancreatitis, or reflux disease. Diagnostic laparoscopy provides the definitive diagnosis of omental infarction, but it is invasive and limited due to resources. Computed tomography of the abdomen and pelvis has been considered the gold standard to diagnosing omental infarction when a non-invasive diagnostic approach is required. Additionally, ultrasound can also be used alternatively for children. Currently, there is no consensus in the diagnosis and management of patients with imaging-proven omental infarction. Spontaneous infarcted omentum must be considered by surgeons and radiologists as a rare cause of acute abdominal pain as patients can experience good outcomes with either conservative or operative approach. However, conservative management must only be considered in stable patients where alternative pathology is unlikely.
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  • 文章类型: Journal Article
    这份简短的报告旨在展示光子计数技术以及标准的颅骨成像协议在患者的颅骨计算机断层扫描中可视化分流阀的实用性。回顾性调查了具有颅骨协议的光子计数CT扫描,并遇到了四种类型的分流阀:proGAV2.0®,M.blue®,CodmanCertas®,和proSA®。将这些扫描与相同患者在不同时间点从非光子计数扫描仪获得的扫描进行比较。对这些发现的分析表明,光子计数技术可用于清晰,精确地可视化分流阀,而无需任何额外的辐射或特殊的重建模式。与其他CT探测器相比,提供了出色的空间分辨率,从而突出了光子计数的增强实用性。该技术有助于更准确地表征分流阀,并且可以支持细微异常的检测和分流阀的精确评估。
    This brief report aimed to show the utility of photon-counting technology alongside standard cranial imaging protocols for visualizing shunt valves in a patient\'s cranial computed tomography scan. Photon-counting CT scans with cranial protocols were retrospectively surveyed and four types of shunt valves were encountered: proGAV 2.0®, M.blue®, Codman Certas®, and proSA®. These scans were compared with those obtained from non-photon-counting scanners at different time points for the same patients. The analysis of these findings demonstrated the usefulness of photon-counting technology for the clear and precise visualization of shunt valves without any additional radiation or special reconstruction patterns. The enhanced utility of photon-counting is highlighted by providing superior spatial resolution compared to other CT detectors. This technology facilitates a more accurate characterization of shunt valves and may support the detection of subtle abnormalities and a precise assessment of shunt valves.
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  • 文章类型: Journal Article
    这项研究提供了光子计数探测器(PCCT)和能量集成探测器(EID)之间的颅骨计算机断层扫描(CT)成像质量和辐射剂量的客观比较。我们回顾性分析了76例患者的158例CT扫描,在同一个体上使用两种检测器类型以确保一致的比较。我们的分析集中在计算机断层扫描剂量指数和剂量长度乘积以及脑灰质和白质的对比度噪声比和信噪比上。我们利用标准化的成像协议和一致的患者定位来最小化变量。PCCT显示出更高的图像质量和更低的辐射剂量的潜力,正如这项研究所强调的那样,从而在减少辐射暴露的情况下实现诊断清晰度,强调其在病人护理中的重要性,特别是对于需要多次扫描的患者。结果表明,虽然这两个系统都是有效的,PCCT在神经放射学评估中提供了增强的成像和患者安全性。
    This study provides an objective comparison of cranial computed tomography (CT) imaging quality and radiation dose between photon counting detectors (PCCTs) and energy-integrated detectors (EIDs). We retrospectively analyzed 158 CT scans from 76 patients, employing both detector types on the same individuals to ensure a consistent comparison. Our analysis focused on the Computed Tomography Dose Index and the Dose-Length Product together with the contrast-to-noise ratio and the signal-to-noise ratio for brain gray and white matter. We utilized standardized imaging protocols and consistent patient positioning to minimize variables. PCCT showed a potential for higher image quality and lower radiation doses, as highlighted by this study, thus achieving diagnostic clarity with reduced radiation exposure, underlining its significance in patient care, particularly for patients requiring multiple scans. The results demonstrated that while both systems were effective, PCCT offered enhanced imaging and patient safety in neuroradiological evaluations.
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