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《Radiography》2022,28(4):964-972
IntroductionThe British Institute of Radiology (BIR) and American Association of Physicists in Medicine (AAPM) have recommended that gonad shielding is no longer used during pelvic X-ray examinations. The BIR guidance states that shielding may still be considered for use on males, but should not be used on females. This paper aimed to evaluate if this decision was supported by evidence from practice, by comparing the accuracy of gonad shield placement in paediatric males and females.MethodsA systematic review of databases including EMBASE, MEDLINE and PubMed was performed in February 2021. Studies were considered eligible if they provided data on the use of gonad shielding during pelvic X-ray examinations on male and female patients under the age of 18. Nine studies met the inclusion criteria and data extraction was performed. Quality appraisal was undertaken, and a meta-analysis of shielding accuracy was performed on seven studies.ResultsThe results from the meta-analysis (2187 total radiographs) demonstrated that female patients were significantly more likely (OR 1.38, 95% CI 0.88–1.87) than males to have gonad shields placed inaccurately (p value < 0.001).ConclusionGonad shield placement on paediatric female patients is significantly less accurate than on males, and so the results support the AAPM and BIR guidance to stop the practice for females. Shield application may also be frequently inaccurate for males, but the review does not provide clear evidence for or against continuing the practice for males.Implications for practiceDiscontinuing the use of gonad shields in paediatric pelvic radiography on female patients is supported. Any continued use on male patients, or for reasons such as psychological reassurance, should be subject to enhanced training and audit to ensure benefits outweigh any risks.  相似文献   
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目的探讨采用基于"人工智能(AI)的骨龄辅助评价系统(上海初云医疗科技有限公司与四川大学华西第二医院合作开发)"(以下简称为AI系统)对完全性生长激素缺乏症(CGHD)患儿诊断及骨龄评价准确性。 方法选择2014年7月至2019年11月,于四川大学华西第二医院确诊的66例来自四川地区CGHD患儿为研究对象,纳入研究组。选择同期于病例收集医院儿童保健科进行骨龄测定的67例来自四川地区身高达标儿童作为对照,纳入对照组。对每例受试儿进行左手腕关节正位X射线摄片骨龄测定,由2位医师采用《TW2骨龄评分法中国未成年人南方标准》(以下简称为TW2CHN)》与《TW3骨龄评分法标准》(以下简称为TW3),盲法评价受试儿TW2CHN-桡、尺、掌指骨(RUS)与TW2CHN-腕骨(carpal)、TW2CHN-20、TW3-RUS及TW3-carpal骨龄(以下简称为5种传统骨龄),以及以同性别、年龄身高达标儿童5种传统骨龄为标准,计算受试儿5种传统骨龄百分位数。同时,采用AI系统分别对每例受试儿采取TW2CHN与TW3法,评价其AI-TW2CHN-RUS、AI-TW2CHN-carpal、AI-TW2CHN-20、AI-TW3-RUS及AI-TW3-carpal骨龄(以下简称为5种AI骨龄)及其相应百分位数。以上述5种传统骨龄+5种AI骨龄(以下简称为10种骨龄)相应的P50、P25、P10、P3值(统称为Pn值)作为诊断CGHD患儿临界值,分别计算其诊断CGHD患儿的敏感度、特异度、约登(Youden)指数、准确率、阳性似然比、阴性似然比、阳性预测值、阴性预测值。采用Kappa值评价2组受试儿5种传统骨龄百分位数与对应的5种AI骨龄百分位数评价结果的一致性,以及2位医师对2组受试儿TW2CHN-RUS骨龄百分位数评价结果一致性。绘制上述10种骨龄百分位数诊断CGHD患儿的受试者工作特征(ROC)曲线,并计算曲线下面积(AUC)。采用配对t检验,对2组受试儿TW2CHN骨龄与TW3骨龄进行比较。本研究遵循的程序符合2013年新修订的《世界医学协会赫尔辛基宣言》要求。2组受试儿年龄、性别构成比等一般临床资料比较,差异均无统计学意义(P>0.05)。 结果①采用10种骨龄的Pn值分别作为诊断CGHD临界值,对133例受试儿CGHD诊断结果显示,除了TW3-RUS骨龄中,以骨龄≤P10作为诊断CGHD患儿临界值时的诊断准确率最高(85.0%),TW2CHN-RUS、TW2CHN-carpal、TW2CHN-20、TW3-carpal、AI-TW2CHN-RUS、AI-TW2CHN-carpal、AI-TW2CHN-20、AI-TW3-carpal、AI-TW3-RUS骨龄中,均为以骨龄≤P25作为临界值时,对CGHD的诊断准确率最高,分别为81.9%、75.2%、88.0%、78.2%、75.2%、73.6%、81.2%、72.9%、78.9%。②一致性检验结果显示,2组受试儿TW2CHN-RUS与AI-TW2CHN-RUS、TW2CHN-carpal与AI-TW2CHN-carpal、TW2CHN-20与AI-TW2CHN-20、TW3-RUS与AI-TW3-RUS、TW3-carpal与AI-TW3-carpal骨龄百分位数评价结果均为中等一致性,Kappa值分别为0.445、0.578、0.570、0.446、0.430(均为P<0.001)。③对2位医师对2组受试儿TW2CHN-RUS骨龄百分位数评价结果进行一致性检验显示,其Kappa值为0.790(P<0.001),一致性较高。④绘制10种骨龄百分位数评价结果诊断CGHD的ROC曲线分析结果显示,TW2CHN-RUS、TW2CHN-carpal、TW2CHN-20、TW3-carpal、TW3-RUS、AI-TW2CHN-RUS、AI-TW2CHN-carpal、AI-TW2CHN-20、AI-TW3-carpal、AI-TW3-RUS骨龄百分位数诊断CGHD患儿的AUC分别为0.932、0.859、0.915、0.895、0.844、0.823、0.805、0.866、0.860、0.764(均为P<0.001)。⑤133例受试儿的TW3-RUS、TW3-carpal、AI-TW3-RUS、AI-TW3-carpal骨龄,均分别显著低于TW2CHN-RUS、TW2CHN-carpal、AI-TW2CHN-RUS、AI-TW2CHN-carpal骨龄,并且差异均有统计学意义(t=21.746、25.287、16.498、9.290,P<0.001)。 结论TW2CHN法、TW3法对CGHD患儿骨龄评价及诊断均有临床价值,TW2CHN-RUS骨龄对于CGDH患儿诊断效能高。四川地区儿童TW3骨龄较TW2CHN骨龄低,TW3法可能不完全适用于四川地区儿童骨龄评价。AI系统对于四川地区CGHD患儿骨龄评价结果与传统骨龄评价结果具有中等一致性,可为临床医师评价受试儿骨龄提供帮助。  相似文献   
4.
目的 评价CT引导下经皮二次穿刺活检用于明确诊断肺部病变的可行性及安全性。方法 回顾性分析40例接受2次肺穿刺活检患者的临床、影像学及随访资料,根据最终诊断结果,比较2次活检的诊断准确率,分析并发症及初次活检误诊的危险因素。结果 40例中,17例初次活检诊断结果与最终诊断一致(确诊组)、23例诊断不一致(误诊组),诊断准确率为42.50%(17/40),并发症发生率为27.50%(11/40);39例二次活检诊断结果与最终诊断一致,诊断准确率为97.50%(39/40),并发症发生率为25.00%(10/40)。二次活检诊断准确率明显提高,并发症发生率与初次活检差异无统计学意义(P>0.05)。组间病灶性质和气胸发生率差异均有统计学意义(P均<0.05)。结论 CT引导下经皮二次穿刺活检用于明确诊断肺部病变安全、可行。  相似文献   
5.
《Dental materials》2022,38(6):924-934
ObjectivesTo study the oxide layer stability of certified dental implants of system "P", made based on TiO2 alloy with carbon coating. To perform a comparative statistical analysis of the obtained data with the available data for the dental implants of systems "A" and "B".MethodsX-ray microtomography and X-ray fluorescence analysis were used to study soft tissue biopsy specimens. Supernatants were studied by dynamic light scattering and transmission electron microscopy when simulating free emission of nanoscale metal oxide particles from the surface of dental implants as well as when simulating physical loading. A comparative analysis of three parameters of nanoscale particles was performed by statistical data analysis. The surface of the "P" system dental implant with surface treatment was analyzed by scanning electron microscopy.ResultsBoth free emission of nanoscale oxide layer particles and yield of nano- and microscale particles during simulation of physical load were confirmed. Statistically significant differences were noted in a comparative analysis of the size and frequency of occurrence of these particles in the supernatants obtained from the surfaces of three dental implant systems. The elemental composition of the particles and the composition and structure of the "P" system dental implants themselves were analyzed.SignificanceThe developed method of dynamic light scattering can be used to compare the stability of the oxide layer of standardized medical products manufactured on the basis of the TiO2 alloy.  相似文献   
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《中国现代医生》2020,58(9):144-146+封三
目的探讨MSCT在对比剂外渗的急性腹部创伤性动脉损伤诊断中的应用价值。方法回顾性分析本院2016年1月~2018年12月收治的44例急性创伤性腹部动脉损伤患者及58例腹部非创伤性动脉病变患者影像资料,分析急性腹部创伤性和非创伤性动脉病变所致对比剂外渗的相关性。结果 44例创伤性腹部损伤患者通过MSCT及图像后处理技术共检出59支动脉损伤,其中对比剂外渗34支、非对比剂外渗共25支;58例急性腹部非创伤组共检出58支动脉病变,其中8支存在对比剂外渗。对比剂外渗征象创伤组出现率明显高于非创伤性组(χ~2=24.42,P0.05)。结论与非创伤组相比,急性腹部创伤性动脉损伤对比剂外渗征象较为常见,MSCT可以较好地显示创伤性对比剂外渗的直接及间接征象。  相似文献   
8.
Chondrosarcoma is the second most common form of bone cancer and is characterized by its ability to produce an extracellular matrix of the cartilage. High-grade chondrosarcoma is highly aggressive and can metastasize to other parts of the body. Chondrosarcoma is resistant to both conventional chemotherapy and radiotherapy; hence, the current main treatment is still surgical resection. Doxorubicin (Dox) has been shown to significantly improve patient survival compared with untreated chondrosarcoma. However, for patients with metastasis, surgical resection alone can hardly treat them. In addition, drug resistance is one of the leading causes of death in patients with chondrosarcoma. Secreted proteins can mediate cell-cell interactions in the cancer microenvironment, which may be associated with the development of drug resistance. In the present study, chondrosarcoma cells were treated with Dox, the conditioned medium was then collected and changes in secreted proteins were analyzed using the antibody array. Results showed that the Dox-treated group had the highest secretion of basic fibroblast growth factor (bFGF), indicating the effect of bFGF on Dox sensitivity in chondrosarcoma. Furthermore, lentiviral-mediated knockdown and treatment of exogenous recombinant protein were employed to further investigate the effect of bFGF on Dox resistance. Results demonstrated that bFGF can promote the expression of X-ray repair cross-complementing protein 5 (XRCC5), leading to Dox resistance. Secreted bFGF is likely to be detected in serum, in addition to being a biomarker for predicting Dox resistance, the combination of Dox and bFGF/XRCC5 blockers may be a new therapeutic strategy to improve the efficacy of Dox in future.  相似文献   
9.

Purpose

Anorexia nervosa (AN) is a chronic and life-threatening eating disorder that can have a considerable negative impact on the growing skeleton. We hypothesized that the long-term impact on bone health may persist even after normalization of body weight.

Methods

41 females (mean age 21.2 ± 2.9 years) with a history of adolescent-onset AN attended a follow-up bone health assessment at 5 years (T5, n?=?28) or 10 years (T10, n?=?13) after their first AN-related hospital admission. Assessment included dual-energy x-ray absorptiometry measurements of the total body, lumbar spine, and proximal femur, peripheral quantitative computed tomography at the radius and tibia, anthropometric measurements, serum biochemistry, fracture history, and a patient questionnaire.

Results

A recovery in body weight and BMI was seen for both the T5 and T10 cohorts (BMI at intake 16.6, BMI at T5-T10 21.2-21.3). Dual-energy x-ray absorptiometry body composition indicated a recovery of fat mass and lean tissue mass. Total BMD was unaffected, but reductions were seen at the femoral neck and arms. Peripheral quantitative computed tomography showed reduced trabecular and cortical bone in the radius, and cortical thinning in the tibia. AN patients showed a statistically significant reduction in measures of radiographic bone health at follow up, although not to a degree that necessitated clinical intervention. Serum insulin-like growth factor 1 was also positively correlated with total BMD and BMC measures. While fracture risk was not increased, a subset of participants (8%) showed multiple (>4) fractures.

Conclusion

A longitudinal study of adolescent AN showed persisting negative effects on bone health.  相似文献   
10.
ObjectiveTo evaluate the cost-effectiveness of a number of follow-up guidelines and variants for subsolid pulmonary nodules.MethodsWe used a simulation model informed by data from the literature and the National Lung Screening Trial to simulate patients with ground-glass nodules (GGNs) detected at baseline computed tomography undergoing follow-up. The nodules were allowed to grow and develop solid components over time. We tested the guidelines generated by varying follow-up recommendations for low-risk nodules, that is, pure GGNs or those stable over time. For each guideline, we computed average US costs and quality-adjusted life-years (QALYs) gained per patient and identified the incremental cost-effectiveness ratios of those on the efficient frontier. In addition, we compared the costs and effects of the most recently released version of the Lung Computed Tomography Screening Reporting and Data System (Lung-RADS), version 1.1, with those of the previous version, 1.0. Finally, we performed sensitivity analyses of our results by varying several relevant parameters.ResultsRelative to the no follow-up scenario, the follow-up guideline system that was cost-effective at a willingness-to-pay of $100,000/QALY and had the greatest QALY assigned low-risk nodules a 2-year follow-up interval and stopped follow-up after 2 years for GGNs and after 5 years for part-solid nodules; this strategy yielded an incremental cost-effectiveness ratio of $99,970. Lung-RADS version 1.1 was found to be less costly but no less effective than Lung-RADS version 1.0. These findings were essentially stable under a range of sensitivity analyses.ConclusionsCeasing follow-up for low-risk subsolid nodules after 2 to 5 years of stability is more cost-effective than perpetual follow-up. Lung-RADS version 1.1 was cheaper but similarly effective to version 1.0.  相似文献   
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