3D image segmentation using combined shape-intensity prior models

Objective Statistical models for medical images have been developed to increase robustness in the segmentation process. In this project, a fully automatic approach to build a statistical shape-intensity model and combine this model with level set segmentation was designed, implemented and tested by applying the algorithm to clinical image data. Methods By using a hierarchical registration approach based on mutual information and demons registration, 3D statistical shape-intensity models were created by applying Principal Component Analysis. Using these models in combination with level set segmentation results in a fully automatic modeling and segmentation pipeline. Results Examples for shape-intensity models were synthesized and these models were used to automatically segment 3D MRI and CT images. Quantitative evaluation of the framework was performed by comparing automatic segmentation results to segmentation results of medical experts. Conclusion Evaluation tests in which this method was used for the automatic segmentation of femora and cardiac MRI endocardial surfaces are very promising. The implementation of an additional cost function term and the addition of information about the surroundings of an organ in the model are currently under development.     

情志护理对肝癌手术患者希望水平及生活质量的影响

目的 探讨情志护理对肝癌手术患者希望水平及生活质量的影响.方法 选取该院普通外科于2014年3月~2015年10月收治的100例肝癌手术患者为研究对象,根据随机数表法将其分为观察组与对照组,各50例.对照组患者予以常规护理,观察组采用情志护理干预.比较两组患者护理前后的希望水平、生活质量、抑郁程度、睡眠质量及满意度.结果 护理干预后两组希望水平评分均显著升高,且观察组高于对照组,差异有统计学意义(均P<0.05).护理后观察组躯体功能、认知功能、社会功能及情绪功能评分均显著高于对照组,差异有统计学意义(均P<0.05).护理后两组抑郁评分均显著降低,且观察组降低趋势显著高于对照组,差异有统计学意义(P<0.05).护理干预后,对照组满意率明显低于观察组,差异有统计学意义(P<0.05).结论 与常规普外科护理相比,情志护理应用效果更好,可明显提高肝癌手术患者的生活质量及睡眠质量,缓解患者的负面情绪,增加患者治疗疾病的信心,值得临床推广应用.     

A level crossing enhancement scheme for chest radiograph images

A new approach for contrast enhancement of chest radiograph image data is presented. Existing methods for image enhancement focus mainly on the properties of the image to be processed while excluding any consideration of the observer characteristics. In several applications, particularly in the medical imaging area, effective contrast enhancement for diagnostic purposes can be achieved by including certain basic human visual properties. In this paper we shall present a novel (recursive) algorithm that tailors the required amount of contrast enhancement based on a combination of the optimal phase representation and the theory of projection onto a convex set. Constraints of maximum bandwidth of the image data, appropriate knowledge of the amplitude value of the image data, heuristic limitations and level crossing measurements serve to impose additional information. So that, the enhanced image data may better converge to the good quality image.     

广东省部分核医学诊疗工作场所辐射水平及人员受照剂量分析

目的 了解广东省部分临床核医学诊疗工作场所的放射防护状况以及人员受照剂量水平,为寻找其放射性职业病危害的关键控制点提供数据支持。方法 以广东省14家三级甲等综合性医院为研究对象,根据国家相关标准,采用辐射监测方法,对临床核医学工作场所的周围剂量当量率、放射性污染水平及人员受照剂量进行测量和推算。结果 工作场所中¹⁸F合成室操作孔在防护罩打开状态下的周围剂量当量率最高,达到166 μSv/h;放射性药物分装、注射等操作环节手部的剂量率较高,其中在分装柜分装¹⁸F、¹³¹I和⁹⁹Tc^m时可分别高达3720、1220和468.2 μSv/h,在注射台（窗）注射¹⁸F和⁹⁹Tc^m时可分别高达537和882 μSv/h。广州G医院¹⁸F注射室的工作台面β表面污染水平为99.6 Bq/cm²,工作人员手掌部位为1.6 Bq/cm²,超过国家标准限值。核医学工作人员年有效剂量为0.08~5.18 mSv/a。在无防护措施的前提下,分装人员手部的年当量剂量最高,为0.02~390 mSv/a;注射人员次之,为0.57~85.62 mSv/a;而分装、注射时工作人员眼晶体、全身和下腹部的职业照射剂量较低。结论 核医学工作场所的放射防护现况良好;应重视放射工作人员自身防护,熟练操作技能以缩短作业时间,采取合理防护设（措）施以降低辐射剂量。