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1.

Background

Purulent bacterial pericarditis is a rare and potentially fatal disease. The course may be fulminant, and the presentation may pose a diagnostic challenge.

Case report

An otherwise healthy 75-year-old male was brought to the emergency department in a state of general deterioration, confusion, and shock. Bedside ultrasound showed a significant pericardial effusion. His condition quickly deteriorated and the resuscitation included emergent bedside pericardiocentesis. The drainage was purulent and later cultures grew out Streptococcus pneumoniae.

Why should an emergency physician be aware of this?

Purulent pericarditis is extremely rare but should be considered in the patient with a fulminant infectious process (particularly pneumonia) and signs of pericardial effusion. Treatment should include appropriate antibiotics and early drainage.  相似文献   
2.
Dynamic contrast-enhanced ultrasound (DCE-US) has been proposed as a powerful tool for cancer diagnosis by estimation of perfusion and dispersion parameters reflecting angiogenic vascular changes. This work was aimed at identifying which vascular features are reflected by the estimated perfusion and dispersion parameters through comparison with acoustic angiography (AA). AA is a high-resolution technique that allows quantification of vascular morphology. Three-dimensional AA and 2-D DCE-US bolus acquisitions were used to monitor the growth of fibrosarcoma tumors in nine rats. AA-derived vascular properties were analyzed along with DCE-US perfusion and dispersion to investigate the differences between tumor and control and their evolution in time. AA-derived microvascular density and DCE-US perfusion exhibited good agreement, confirmed by their spatial distributions. No vascular feature was correlated with dispersion. Yet, dispersion provided better cancer classification than perfusion. We therefore hypothesize that dispersion characterizes vessels that are smaller than those visible with AA.  相似文献   
3.
In the work described here, our aim was to determine, in an elderly population, changes in muscle thickness (MT), cross-sectional area (CSA) and echo intensity (EI) of the quadriceps muscles at four time points (0, 5, 10 and 15 min; i.e., T0, T5, T10 and T15, respectively) after changing from a standing to supine position. Twenty-one elderly participants (14 men: 68.1 ± 4.6 y; 8 women: 66.8 ± 4.1 y) were evaluated at four time points. Rectus femoris CSA (RFCSA), MT and EI of the quadriceps femoris (QF) muscles were assessed. EI significantly increased from T0 to T5, T10 and T15 (p < 0.001), whereas no differences were observed between T5 and T15 in the rectus femoris (RFEI), vastus intermedius (VIEI) and quadriceps femoris (QFEI). No differences were observed between any time points in the RFCSA and MT of QF muscles. In summary, these results suggest that periods >5 min are not necessary to obtain consistent MT and EI measurements of quadriceps femoris muscles in the elderly population.  相似文献   
4.

Background

In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.

Objectives

The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.

Methods

This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.

Results

A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.

Conclusions

In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation.  相似文献   
5.
ObjectivesTo compare fetal anterior abdominal wall thickness (AAWT) between women with and without GDM during third trimester and to determine accuracy of AAWT to predict large for gestational age (LGA) infants.Materials and methodsA total of 250 pregnant women, including 125 women with GDM and 125 women without GDM, were enrolled. Tansabdominal ultrasonographic examinations were performed at 28–30, 32–34 and 36–38 weeks. In addition to standard fetal biometries, AAWT was measured. Patient characteristics and ultrasonographic measurements were compared between groups. Sensitivity and specificity of AAWT for identifying LGA were evaluated.ResultsWhile standard fetal biometries were comparable, mean fetal AAWT in GDM women were significantly higher than those without GDM at 28–30 weeks (2.8 ± 0.8 vs. 2.6 ± 0.6, p = 0.006) and 32–34 weeks (4.0 ± 0.9 vs. 3.5 ± 0.8, p = 0.042). LGA infants had significantly higher fetal AAWT at each time point only in GDM women. Using cut off values of AAWT of ≥2.0, 3.0, and 4.0 mm at 28–30, 32–34, and 36–38 weeks, sensitivity for LGA diagnosis in GDM women were 94.4%, 93.9%, and 89.3%, respectively. The use of abdominal circumference (AC) at >90th percentile showed lower sensitivity but higher specificity, regardless of GDM status. Combination of both measurements increased sensitivity to approximately 90% or higher in every time point, especially among GDM women.ConclusionSignificant increase in fetal AAWT was observed in GDM women at 28–30 and 32–34 weeks. Fetal AAWT significantly increased among LGA infants and had higher sensitivity than AC in identifying LGA during third trimester. In GDM women at 28–30 weeks, AAWT ≥2.0 mm and AC >90th percentile had 97.2% sensitivity for LGA diagnosis.  相似文献   
6.
The primary aim of this study was to evaluate the accuracy of sonographic estimation of fetal weight when performed at due date by first-line sonographers. This was a prospective study including 500 singleton pregnancies. Ultrasound examinations were performed by residents on delivery day. Estimated fetal weights (EFWs) were calculated and compared with the corresponding birth weights. The median absolute difference between EFW and birth weight was 200 g (100–330). This difference was within ±10% in 75.2% of the cases. The median absolute percentage error was 5.53% (2.70%–10.03%). Linear regression analysis revealed a good correlation between EFW and birth weight (r = 0.79, p < 0.0001). According to Bland–Altman analysis, bias was −85.06 g (95% limits of agreement: −663.33 to 494.21). In conclusion, EFWs calculated by residents were as accurate as those calculated by experienced sonographers. Nevertheless, predictive performance remains limited, with a low sensitivity in the diagnosis of macrosomia.  相似文献   
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9.
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease.  相似文献   
10.
经皮肺动脉瓣植入术(PPVI)在我国作为一种新兴的技术,开展相对较晚,但随着我国医疗水平的不断提高以及临床对于右心室流出道梗阻的先天性心脏病患者术后出现重度肺动脉瓣反流的不断重视,PPVI在我国得到了飞速发展。近十几年来,欧美国家已在临床成熟应用PPVI,相对于传统外科手术而言其具有微创、可重复性、术后疗效好等优点。现对PPVI在肺动脉瓣反流患者中的临床应用进行叙述。  相似文献   
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