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Introduction and ObjectivesThe 2019 ESC guidelines on chronic coronary syndromes updated the method for estimating the pre-test probability (PTP) of obstructive coronary artery disease (CAD). We aimed to compare the performance of the new PTP method against the 2013 prediction model in patients with stable chest pain undergoing coronary computed tomography angiography (CCTA) for suspected CAD.MethodsWe conducted a single-center cross-sectional study enrolling 320 consecutive patients undergoing CCTA for suspected CAD. Obstructive CAD was defined as any ≥50% luminal stenosis on CCTA. Whenever invasive coronary angiography was subsequently performed, patients were reclassified accordingly. The two PTP prediction models were assessed for calibration, discrimination and the ability to change the downstream diagnostic pathway.ResultsThe observed prevalence of obstructive CAD was 16.3% (n=52). The 2013 prediction model significantly overestimated the likelihood of obstructive CAD (relative overestimation of 130%, p=0.005), while the updated 2019 method showed good calibration (relative underestimation of 6.5%, p=0.712). The two approaches showed similar discriminative power, with C-statistics of 0.73 (95% CI: 0.66-0.80) and 0.74 (95% CI: 0.66-0.81) for the 2013 and 2019 methods, respectively (p=0.933). Reclassification of PTP using the new method resulted in a net reclassification improvement of 0.10 (p=0.001).ConclusionsThe updated 2019 prediction model provides a more accurate estimation of pre-test probabilities of obstructive CAD than the previous model. Adoption of this new score may improve disease prediction and influence the selection of non-invasive testing.  相似文献   
43.
【摘要】目的 探讨二维斑点追踪显像技术(2D-STI)评估新生儿窒息合并心肌损害后左心室整体及局部心肌的纵向收缩功能在早期诊断窒息新生儿心肌损害中的临床价值。方法 选择2019年07月至2020年12月期间在右江民族医学院附属医院新生儿科住院的足月窒息新生儿61例,经临床确诊合并心肌损害,根据Apgar评分分为轻度组31例和重度组30例,选择同期住院出生的正常足月新生儿30例作为对照组。检测受检者的血清肌酸激酶同工酶(CK-MB)、肌钙蛋白(cTnT)、左室舒张期前后径(LVDId)、左室射血分数(LVEF)、左室短轴缩短率(LVFS)、辛普森法左室射血分数(Simpson EF)、左室三腔心整体应变(GLS-LAX)、左室四腔心整体应变(GLS-A4C)、左室两腔心整体应变(GLS-A2C)、左室整体应变(GLS-AVG),分析GLS-AVG和CK-MB、cTnT三者的相关性。结果 三组间CK-MB和cTnT比较差异有统计学意义(P<0.05)。三组间性别、体重、胎龄均无统计学差异(P>0.05)。三组间LVDId、LVEF、LVFS、Simpson EF比较差异无统计学意义(P>0.05)。GLS-AVG与CK-MB呈负性相关(r=-0.515,P=0.000),GLS-AVG与cTnT呈负性相关(r=-0.912,P=0.000)。结论 GLS-AVG与CK-MB、cTnT具有相关性,GLS-AVG可作为窒息新生儿心肌损害早期诊断指标。  相似文献   
44.
《Radiography》2022,28(2):353-359
Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff.  相似文献   
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This study explores the feasibility of using diffusion kurtosis imaging (DKI) in the pelvic floor region and assesses the water diffusivity of the pubovisceral muscle. Twenty-seven healthy young nulliparous females underwent DKI at 3.0 T that included 15 gradient directions and three b values (0, 750, and 1500 s/mm2). The diffusion tensor and diffusion kurtosis metrics values of the pubovisceral muscle were measured after image processing. Two independent sample t-tests, a paired-samples t-test, and a nonparametric hypothesis test were performed as appropriate to compare the differences among different metrics. Twenty-six subjects (mean ± standard deviation age, 25 ± 2 years) were successfully analyzed by measuring the diffusion tensor and diffusion kurtosis metrics of the bilateral pubovisceral muscles. The metrics included mean kurtosis, axial kurtosis, radial kurtosis, fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. We found no statistically significant differences for these measurement values between the left and right pubovisceral muscles (p = 0.271–0.931). However, radial kurtosis was greater than axial kurtosis in both pubovisceral muscles (p < 0.001) and axial diffusivity was lower than radial diffusivity in both pubovisceral muscles (p < 0.001). We deem the application of DKI technology to the pelvic floor region to be feasible.  相似文献   
47.
The purpose of this review is to describe the current state of the art in clinical imaging for NICU patients, divided into major areas that correspond to likely phenotypes of neonatal respiratory disease: airway abnormalities, parenchymal disease, and pulmonary vascular disease. All common imaging modalities (ultrasound, X-ray, CT, and MRI) are discussed, with an emphasis on modalities that are most relevant to the individual underlying aspects of disease. Some promising aspects of dynamic and functional imaging are included, where there may be future clinical applicability.  相似文献   
48.
BackgroundThe epidemiology and clinical characteristics of spinal epidural lipomatosis (SEL) have been well-reported in the literature. However, few studies investigated the concomitant spinal pathologies that were present in patients with SEL. Therefore, we aimed to summarize the clinical and radiological characteristics of patients with SEL diagnosed on spinal imaging.MethodsPatients who were diagnosed with SEL on magnetic resonance imaging from January 2018 to October 2020 at our institution were included in the study. Clinical data was collected using a standardized data collection form. SEL was graded using a modified version of the Borré grading system. Factors associated with moderate or severe SEL were determined using multiple logistic regression.ResultsA total of 90 patients were included in the analysis. The mean (±SD) age was 59.3 (±17.1) years, and 62 patients (68.9%) were male. 61 patients (67.8%) had moderate or severe SEL. Most patients were overweight or obese (57 patients, 63.3%). The most common presenting symptoms was back pain (57 patients, 63.3%). SEL was diagnosed incidentally in 42 patients (46.7%). The lumbar spine was the most common site of SEL (35 patients, 38.9%). The most common concomitant spinal pathologies were disc bulge (83 patients, 92.2%) and flavum hypertrophy (60 patients, 66.7%). Moderate or severe SEL was associated with WHO Obesity Class, back pain or radicular leg pain at first presentation, and SEL that was worst at the lumbar or lumbosacral spinal level.ConclusionsModerate or severe SEL were independently associated with WHO Obesity Class, back pain, radicular leg pain, and SEL that was worst at the lumbar or lumbosacral spinal level. Future studies should prospectively evaluate whether weight loss therapy is warranted in patients with SEL.  相似文献   
49.
IntroductionPremature children birth and survival is becoming more frequent due to the improvement in obstetric and neonatal care. This makes it increasingly common to find patients with history of preterm birth in ophthalmology clinics, both in pediatric and adult ages. Premature birth can lead to ocular structural changes, being possible to affect the ganglion cell complex (GCC), among other structures, which can be studied using optical coherence tomography.Materials and methodsTo carry out a bibliographic review of the studies that analyze GCC in patients with a history of prematurity compared with patients born at term.ResultsSeveral studies that analyze GCC in patients with a history of prematurity are referenced and their results are studied.ConclusionsIn our clinical practice, knowing the history of prematurity is fundamental in the assessment of GCC measured by optical coherence tomography, since this layer is different in the patients with a history of prematurity compared to patients born at term.  相似文献   
50.
ObjectiveThe objective of this study was to investigate the association between morphological variation and postsurgical pulmonary vein (PV) stenosis (PPVS) in patients with cardiac total anomalous pulmonary venous connection (TAPVC).MethodsThis single-center, retrospective study included 168 pediatric patients who underwent surgical repair of cardiac TAPVC from 2013 to 2019 (connection to the coronary sinus [CS], n = 136; connection directly to the right atrium [RA], n = 32). Three-dimensional computed tomography modeling and geometric analysis were performed to investigate the morphological features; their relevance to the PPVS was examined.ResultsThe connection type had no association with PPVS (CS type: 18% vs right atrial type: 19%; P = .89) but there was a higher incidence of PPVS in patients with a single PV orifice than > 1 orifice (P < .001). Confluence-to-total PV area ratio (hazard ratio, 4.78, 95% CI, 1.86-12.32; P = .001) and length of drainage route (hazard ratio, 1.22; 95% CI, 1.14-1.31; P < .001) had a 4- and 1-fold increase in the risk for PPVS in the CS type after adjustment for age and preoperative pulmonary venous obstruction. In the right atrial type, those with anomalous PV return to the RA roof were more likely to develop PPVS than to the posterior wall of the RA (P < .001).ConclusionsThe number of inter-junction PV orifice correlated with PPVS development in cardiac TAPVC. The confluence-to-total PV ratio, length of drainage route, and anomalous PV return to the RA roof are important predictors for PPVS. Morphological subcategorization in this clinical setting can potentially assist in surgical decision-making.  相似文献   
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