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IntroductionDating the exact or estimated time of trauma is an important issue facing forensic medicine. Several clinical and radiological methods were used to achieve this purpose. In the recent study, we aimed to track the changes in the signal intensity of the extra-axial brain hematoma using magnetic resonance imaging (MRI) conventional sequences as well as diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC).Materials and methodsConsidering inclusion and exclusion criteria, all patients with blunt head trauma were involved. After proper management., stabilization, and resuscitation, the participants were assessed using conventional sequences of MRI and DWI twenty-four hours, forty-eight hours, and three weeks after the injury. Temporal changes of signal intensity were compared by Wilcoxon ranged test.ResultsSixteen patients sustaining blunt head trauma were included in this study. The study showed that during the time, diffusion restriction could be seen in an extraaxial hematoma. At the first 24 hours, the signal of hematoma was void in 87.5% of DWI and 100% of ADC. On the second day, they were hypo-signal in 75% of DWI and 100% 0f ADCs, and after three weeks, 100% of cases were hyper-signal in DWI and hypo-signal ADCs.ConclusionThis preliminary study has shown that the DWI can be used to detect and track the extra-axial hematoma. The signal intensity was void during the first twentyfour hours, although it became hypo-signal after 48 hours. Of note, the diffusion restriction is noted after three weeks.  相似文献   
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Goal: There is limited research on intracerebral hemorrhage in young urban populations. There is reduced access to healthcare and a high prevalence of multiple comorbidities in this vulnerable population. We studied the etiologies and outcomes of spontaneous intracerebral hemorrhage in an urban North Philadelphia cohort aged 50 years old and younger. Materials and methods: A retrospective chart review of subjects 50 years old and younger who presented with spontaneous intracerebral hemorrhage at Temple University Hospital was conducted. A novel scoring system was used to classify the cause of each intracerebral hemorrhage. This system was used to assign a degree of likelihood that hypertension, amyloid angiopathy, tumor, oral anticoagulants, vascular malformations, infrequent causes, or cryptogenic etiologies were present. Aneurysmal subarachnoid hemorrhage was excluded. The prevalence of each risk factor and outcomes were analyzed. Findings: Of the 110 patients in the study, the most common etiology was hypertension (82.7%). There was no statistically significant difference in mortality between patients with multiple possible etiologies for their hemorrhage. Vascular malformations and cavernomas were rare (5.5%). Conclusions: Hypertension was the most common cause of intracerebral hemorrhage in a young urban population. The presence of multiple possible etiologies does not correlate with a worse prognosis of mortality. There is a need for further research into hemorrhagic stroke in young populations.  相似文献   
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Background and purpose

It is not conclusive that magnetic resonance (MR)-based carotid atherosclerotic plaque assessment identifies high-risk features associated with cerebrovascular events. We aimed to systematically summarize the association of MR imaging (MRI)-determined intraplaque hemorrhage (IPH), lipid-rich necrotic core (LRNC), and thinning/rupture of the fibrous cap (TRFC) with subsequent ischemic events.

Materials and methods

We performed a comprehensive literature search evaluating the association of MRI-based carotid plaque composition with ischemic outcomes. We included cohort studies examining IPH, LRNC, or TRFC with mean follow-up of  6 months and an outcome measure of ipsilateral ischemic events. A meta-analysis was done according to the Cochrane guideline.

Results

We identified 13 studies including 1.150 patients and 1.208 analyzed carotid arteries, with mean follow-up of 21.1 months. The hazard ratios (HR) for IPH, LRNC, and TRFC as predictors of subsequent ischemic events were 4.41 (95% CI: 2.87, 6.79), 3.00 (95% CI: 1.51, 5.95), and 5.94 (95% CI: 2.66, 13.28), respectively. The predictive value of carotid plaque MRI for ischemic events was acceptable, with sensitivity of 0.80 (95% CI: 0.66, 0.90) and specificity of 0.63 (95% CI: 0.57, 0.68). However, it was limited to confirm or exclude future ischemic events in clinical context, with positive likelihood ratio (LR) of 2.2 (95% CI: 1.9, 2.5) and negative LR of 0.31 (95% CI: 0.18, 0.55). No statistically significant heterogeneity or publication bias was observed.

Conclusion

The presence of IPH, LRNC, and TRFC determined by MRI is associated with increased risk of future ischemic events, but its predictive value is moderate and should not be used for confirmation or exclusion of future ischemic events in clinical context.  相似文献   
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Interstitial lung disease (ILD) in children (chILD) is a heterogeneous group of rare respiratory disorders that are mostly chronic and associated with high morbidity and mortality. The pathogenesis of the various chILD is complex and the diseases share common features of inflammatory and fibrotic changes of the lung parenchyma that impair gas exchanges. The etiologies of chILD are numerous. In this review, we chose to classify them as ILD related to exposure/environment insults, ILD related to systemic and immunological diseases, ILD related to primary lung parenchyma dysfunctions and ILD specific to infancy. A growing part of the etiologic spectrum of chILD is being attributed to molecular defects. Currently, the main genetic mutations associated with chILD are identified in the surfactant genes SFTPA1, SFTPA2, SFTPB, SFTPC, ABCA3 and NKX2-1. Other genetic contributors include mutations in MARS, CSF2RA and CSF2RB in pulmonary alveolar proteinosis, and mutations in TMEM173 and COPA in specific auto-inflammatory forms of chILD. However, only few genotype-phenotype correlations could be identified so far. Herein, information is provided about the clinical presentation and the diagnosis approach of chILD. Despite improvements in patient management, the therapeutic strategies are still relying mostly on corticosteroids although specific therapies are emerging. Larger longitudinal cohorts of patients are being gathered through ongoing international collaborations to improve disease knowledge and targeted therapies. Thus, it is expected that children with ILD will be able to reach the adulthood transition in a better condition.  相似文献   
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目的介绍改进后的体视学法测量颅内血肿体积,并验证其准确性。方法在92例颅内出血的CT图像上,同时运用体视法、CT定量法测量颅内血肿体积,以CT定量法的结果为标准验证体视法的准确性。结果按血肿体积大小分为5组,各组CT定量法、体视学法所测得体积采用配对样本的t检验分析P值皆大于0.05,即CT定量法、体视学法所测血肿体积无统计学差异。结论体视学法测量颅内血肿准确可靠,在CT工作站对颅内血肿病例行胶片打印排版时,在图像上加上合适的网格,可方便临床医生快速运用体视法准确测量颅内血肿体积。  相似文献   
8.
Direct-acting oral anticoagulants (DOACs) have emerged as safer, easier-to-manage alternatives to traditional vitamin K antagonists and are used increasingly because they require no monitoring, have a wider therapeutic window, and react less with other drugs. However, there is little consensus on optimal perioperative management when these drugs are used in dermatologic surgery. This article describes the characteristics of DOACs and reviews current evidence on their use in this setting.  相似文献   
9.
BackgroundPrior studies examining bleeding with uterine evacuation have focused on high-volume centers performing over 1100 procedures annually. The aim of this study was to examine associations between blood loss and patient and procedural characteristics in a center performing fewer than 50 procedures annually.MethodsThis retrospective cohort study, with institutional review board approval, utilized procedural codes to identify patients undergoing uterine evacuation procedures between 14 weeks’ and 24 weeks’ gestational age across a 50-month period. The primary outcome was estimated blood loss; secondary outcomes were hemorrhage, transfusion and hospital re-admission. Associations between blood loss and other variables were examined using linear regression models.ResultsCharts of 161 women met inclusion criteria. Median estimated blood loss was 400 mL (IQR 300 mL) with 37% of patients having blood loss of ≥500 mL. In univariate analyses, increased blood loss was associated with later gestational age (P <0.001) and pregnancy termination (P <0.001). In a multiple linear regression model, both remained significant. Each one-week increase in gestational age was associated with a 7.1% mean increase in estimated blood loss (95% CI 2.47% to 11.9%; P=0.003). Patients whose uterine evacuation was indicated for pregnancy termination had an 80.6% increase in blood loss compared with those with pre-operative fetal demise (95% CI 37.5% to 137.2%; P <0.001). Rates of peri-operative transfusion and re-admission for bleeding were <4%.ConclusionWhile blood loss may be greater in low volume centers, our transfusion and re-admission rates were low following second trimester uterine evacuation.  相似文献   
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目的:探讨糖尿病对脑梗死出血转化及各分型发生率的影响,为临床制定诊疗方案及预后评估提供有价值的资料。方法回顾性分析运城市中心医院及平陆县人民医院神经内科2011年1月—2015年6月间收治的495例临床资料完整的脑梗死住院患者,根据是否有糖尿病将所入选患者分为糖尿病组及非糖尿病组,通过查阅患者影像及临床资料,观察2组住院期间脑梗死出血转化发生率及不同分型出血转化发生率情况。结果糖尿病组153例中发生出血转化76例(49.7%),其中脑实质血肿型21例(13.8%);非糖尿病组342例中发生出血转化113例(33.0%),其中脑实质血肿型17例(5.0%),2组比较差异具有统计学意义(P<0.01)。结论糖尿病能增加脑梗死出血转化的发生,并能增加更具临床意义的脑实质血肿型出血转化的发生。  相似文献   
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