基于TwIST-TV正则化算法的肺萎陷电阻抗成像仿真研究

肺部电阻抗成像(EIT)通过配置于人体体表一组阵列电极,利用边界测量信息重建胸腔内部二维断面电导率分布,具有非侵入、无辐射等特点,可用于临床监护.针对EIT逆问题求解的欠定性和病态性,提出一种基于总变差正则化(TV)的两步迭代(TwIST)算法.该算法利用迭代引入TV去噪算子,达到解的双重正则化效果.通过仿真构建不同程度肺痿陷EIT模型,利用该算法进行呼吸状态差分图像再构;同时基于图像提出肺通气总量指数作为客观评价指标.结果表明,与传统Tikhonov正则化算法相比,该算法可达到较好的图像重建质量和鲁棒性,其相应肺通气量指数也更接近于仿真肺痿陷模型变化.从而验证了该算法用于临床肺痿陷EIT通气量监测的可行性.     

一个临床应用的实时电阻抗断层成像系统的设计与初步结果

一个临床应用的实时电阻抗断层成像系统的设计与初步结果１引言电阻抗断层显像（ＥＩＴ）是通过对导电区域表面电阻抗进行测量形成的二维电阻抗分布的图像。阻抗测量是通过贴附于人体的一组电极，并采用一系列的二电极、四电极测量方法进行的，接着使用一种图像重建的算法...     

基于斜位电流注入的磁共振电阻抗成像谐函数Bz重建算法及实验研究

针对斜位电流注入的磁共振电阻抗成像,提出基于斜位电流注入的谐函数Bz电导率重建算法,并建立相应的二维电导率重建方案。在构建磁共振电阻抗成像实验系统的基础上,分别进行电导率分布图像的仿真和测量磁通密度的实验。仿真结果表明,所提出的重建算法能够获得电导率分布的图像,并且硬件系统能够获得对成像物体注入电流时的磁共振图像数据,进一步可以得到成像体内的磁通密度。     

血管造影图像序列中冠状动脉的三维运动估计

提出了由两个角度的单面血管造影图像序列估计冠状动脉骨架树三维运动的算法。首先对冠状动脉造影图像序列进行二维预处理和二维运动估计。然后根据冠脉造影系统的透视投影模型得到两幅不同角度的造影图像之间的几何变换关系，以及空间点三维坐标的计算方法。最后，在对整个图像序列进行分析的过程中，将三维运动估计与重建结合起来，得到各骨架点的三维运动向量。采用临床得到的冠状动脉造影图像序列对算法进行了验证，并分析了误差源。     

二维超声与四维超声联合应用于产前胎儿筛查的临床研究

目的探讨二维超声与四维超声联合诊断胎儿畸形的临床效果,并分析其应用价值。方法随机选取2014年1月至2015年1月到我院进行产检的2099例孕妇,对其进行二维超声检查以及联合应用四维超声检查,以及对其分娩、随访结果进行对比分析。结果在产前胎儿畸形筛查中,联合应用二维超声与四维超声检出准确率(93.3%)要明显高于二维超声单独检出准确率(75.6%),特别对于胎儿体表畸形的检出准确率更为明显。结论二维超声具有图像清晰、检查简便、经济安全等优点,四维超声是二维超声的有益补充,能够提供动态诊断信息,联合应用二维超声与四维超声技术,能够明显提高诊断产前胎儿畸形的准确率,有效降低漏诊,具有较高的临床推广价值。     

基于三维模型的断层图像结构定位的初步研究

目的:研究利用初步建立的三维模型确定二维断层图像感兴趣结构像素坐标的方法.方法:通过Photoshop图像处理软件绘制断面图像,使用可视化工具包VTK的移动立方体表面重建算法,在VC++6.0的编译环境下对其进行三维重建以及立体显示.用自行开发的坐标转换处理程序对三维模型上提取的坐标值进行处理,计算断层图像相应结构的像素坐标.结果:建立了一个表面带有S型凹槽的三维模型,通过计算三维模型上凹槽结构的一系列坐标,得到二维断层图像上相应结构的像素坐标点.结论:本研究以VTK重建的三维模型为基础,提出了一种利用已建成的三维模型来指导二维断层图像结构定位的方法,为人体复杂结构的分割与修正以及某些在二维断层图像上无法识别的结构的定位提供了一种新的手段.     

一种基于图像处理的人眼全自动角膜曲率计研究

提出一种以光学系统成像原理的自动角膜曲率计设计方案,并研制完成实验样机,对样机的检测原理、系统工作原理进行说明.该研究方法是将红外园环照到眼睛角膜,经角膜反射成像在CCD上,首先局部进行边缘检测,求取全局阈值算法进行二值化图像,然后检测出二值化边缘轮廓,最后再用最小二乘拟合的方法,计算测量角膜的曲率参数.用标准角膜模拟眼和人眼进行测试,测量精度达到±0.02 mm,测量时间小于1 s.实验结果表明,该方法可行,可以用于医院等角膜曲率参数测量的场合.     

基于二维X线图像骨组织三维重建的研究进展

医学图像的三维重建是当前国内外图像处理技术研究的热点,基于二维X线图像的三维重建这一新的重建方法在骨科疾病诊疗中的实际应用,不仅能够减少患者的检查费用,检查辐射剂量,更克服了传统的三维重建方式对检查体位的限制。本文结合近年来关于应用二维X线图像进行骨组织三维重建的文献报道,对这一重建方法的重建思路变化以及重建依据的分类进行总结,着重介绍了其在长管状骨、髋膝关节以及脊柱侧凸畸形等方面的应用情况,在对困扰其实际应用的旋转角度限制、图像分割识别等问题进行分析后,认为其必将在人体各组织器官的三维重建中得到应用。     

Freehand三维超声体数据重建的最新研究进展

Freehand三维超声成像系统因其扫描方式自由、能提供更大的成像视角和更高的图像分辨率等优点,比较符合医生习惯和手术室环境,成为近年来超声影像引导介入手术的主要研究方向。Freehand三维超声从一系列不规则的二维B超图像入手,重构器脏结构的三维体数据,并进行三维渲染显示。体数据重建是Freehand三维超声成像系统的关键技术,对提高重建图像质量有着重要的作用。对Freehand三维超声体数据的重建算法进行归纳和分类,比较分析其中的典型算法,最后对Freehand三维超声体数据重建算法的研究状况和未来的发展方向进行展望。     

CT快速二维反投影算法

CT图像重建过程中，标准的二维反投影运算计算量为D(N^3)。本研究提出一种快速二维反投影算法，其计算量仅为D(N^2log2^N)。该快速算法可以并行实现，处理器阵列规模为D(N^2)时，计算量为D(log2^x)。本研究还分析得到快速算法的误差上界，并提出一种改进的快速二维反投影算法以获得更高的计算精度。最后，对算法进行了仿真实验。理论分析及仿真实验结果都表明，本研究的二维反投影算法在CT图像重建过程中有着更高的计算效率，并且具有良好的计算精度。     

基于正交匹配追踪及加速近端梯度的人体三维重建

为提高人体三维结构的重建精度,针对重建过程中字典中原子的最佳选择和结构矩阵的优化问题,结合稀疏表示和低秩约束,提出一种正交匹配追踪追踪及加速近端梯度(OMP-APG)算法,以此为医学领域提供丰富的信息,以辅助医生快速精确地制定出治疗方案。首先,对特征点观测矩阵进行奇异值分解(SVD)分解,利用列文伯格-马夸尔特(LM)算法得到唯一确定的相机旋转矩阵;其次,利用稀疏表示中“最大化逼近”思想,通过正交匹配追踪算法对轨迹基系数进行求解,结合预定义的轨迹基求解出人体三维结构矩阵;最后,根据结构矩阵是一个低秩矩阵,将其秩优化问题转化为核范数最小化问题,利用加速近端梯度算法对人体结构矩阵进一步优化处理。将该算法与稀疏逼近算法进行比较,对伸懒腰、瑜伽、拾物、喝水和跳舞等5组不同的人体运动模型进行三维重建,通过其三维重建效果图和三维重建误差的结果显示,其重建精度更高且稳定性更好。在该算法下喝水运动的重建效果最佳,其1 102帧图像序列41个特征点的重建误差为0.030 3,而在稀疏算法下的重建误差为0.017 8。因此,该算法可以有效地提高人体三维结构的重建精度,为医学领域辅助治疗提供相应的技术支持。     

三维扫描技术精确控制大鼠烫伤面积动物模型的建立

目的 建立一种可精确控制烫伤面积的大鼠模型.方法 40只大鼠被随机分为5组,每组8只,根据接触94℃热水时间不同分别为6 s组、8 s组、10 s组、12 s组、14 s组,以热水接触作为致伤原因,持续时间控制烫伤深度.比较各组创面烫伤深度和愈合时间,并经病理证实.另取9只大鼠作为3D扫描组,接触94℃热水12 s,烫伤24 h后应用3D流动式双目三维扫描技术,扫描计算大鼠体表面积及烫伤部位占体表总面积的百分比,并与实体解剖测量结果进行比较.结果 12 s组烫伤创面深度可达（34.2±2.9）mm,且无毛囊及汗腺附件存在.创面愈合时间为（24.4±2.2）d,病理证实烫伤深度为深Ⅱ度～Ⅲ度;流动式双目三维扫描技术确认的烫伤面积与实体解剖测量所得结果差异无统计学意义（P〉0.05）.结论 以热水接触为致伤原因,配合三维扫描技术测量烫伤面积精确可信,该模型可以控制烫伤深度、精确烫伤面积,是研究烧（创）伤修复机制及评价创面用药的良好动物模型.     

Differences in second-intention wound healing of distal aspect of the limb between Caspian miniature horses and donkeys: macroscopical aspects

In this study, second-intention healing of limb wounds was studied in donkeys and Caspian miniature horses. Full-thickness, rectangular (2?×?3?cm) skin wounds were created on the lateral aspect of left metacarpi of four donkeys and four Caspian horses. Wound healing process was compared between limb wounds of donkeys and Caspian horses by clinical and geometrical assessments, over a 4-week period. At days?0, 3, 7, 10, 14, 17, 21, 24, and 28, digital photographs were taken of all wounds. The area of epithelialization and granulation tissue was measured for each wound using sigma scan software. Percentages of wound contraction, epithelialization, and healing were calculated for each wound. The clinical and geometrical evaluation revealed that there were significant differences in second-intention wound healing patterns between donkeys and Caspian horses. The donkeys limb wound healed much faster and in better condition than the limb wound of the Caspian horses. Based on results of this study, it can be concluded that although Caspian miniature horses and donkeys have same body size, it seems that due to genetic differences, considerable heterogeneity was observed in second-intention wound healing between them.     

Meek皮肤移植修复烧伤创面效果与临床应用价值的Meta分析

背景：近年来关于应用Meek植皮修复烧伤创面有较多临床报道,但就其与传统植皮法相比是否更具优势仍存在争议,且临床研究报道多为小样本对照研究,缺乏说服力。 目的：对Meek植皮修复烧伤创面的疗效及临床应用价值进行系统评价。 方法：计算机检索Cochrane协作网数据库(2009年第12期)、PubMed(1990/2010-12)、Ovid数据库(1966/2011-03),中国生物医学文献数据库(CBM,1979/2010)、万方数据库(1982/2011)和清华同方数据库(CNKI,1979/2010),收集有关Meek植皮法修复烧伤创面的临床对照实验(CCT)。评价纳入研究的方法学质量并进行资料提取后,采用RevMan 5.1软件进行Meta分析。 结果与结论：共纳入10个临床对照实验,包括198例大面积烧伤患者。相比于对照组,Meek植皮组创面愈合时间、皮片融合时间、手术操作时间、手术操作人数和1%总烧伤面积的治疗费用均明显减少,提示Meek植皮与传统植皮方法相比能明显促进烧伤创面的愈合,并且能减少医疗花费,简化手术操作,具有明显的临床应用价值。     

Physical plasma therapy accelerates wound re-epithelialisation and enhances extracellular matrix formation in cutaneous skin grafts

Skin grafting is a surgical method of cutaneous reconstruction, which provides volumetric replacement in wounds unable to heal by primary intention. Clinically, full-thickness skin grafts (FTSGs) are placed in aesthetically sensitive and mechanically demanding areas such as the hands, face, and neck. Complete or partial graft failure is the primary complication associated with this surgical procedure. Strategies aimed at improving the rate of skin graft integration will reduce the incidence of graft failure. Cold atmospheric plasma (CAP) is an emerging technology offering innovative clinical applications. The aim of this study was to test the therapeutic potential of CAP to improve wound healing and skin graft integration into the recipient site. In vitro models that mimic wound healing were used to investigate the ability of CAP to enhance cellular migration, a key factor in cutaneous tissue repair. We demonstrated that CAP enhanced the migration of epidermal keratinocytes and dermal fibroblasts. This increased cellular migration was possibly induced by the low dose of reactive oxygen and nitrogen species produced by CAP. Using a mouse model of burn wound reconstructed with a full-thickness skin graft, we showed that wounds treated with CAP healed faster than did control wounds. Immunohistochemical wound analysis showed that CAP treatment enhanced the expression of the dermal–epidermal junction components, which are vital for successful skin graft integration. CAP treatment was characterised by increased levels of Tgfbr1 mRNA and collagen I protein in vivo, suggesting enhanced wound maturity and extracellular matrix deposition. Mechanistically, we show that CAP induced the activation of the canonical SMAD-dependent TGF- β 1 pathway in primary human dermal fibroblasts, which may explain the increased collagen I synthesis in vitro. These studies revealed that CAP improved wound repair and skin graft integration via mechanisms involving extracellular matrix formation. CAP offers a novel approach for treating cutaneous wounds and skin grafts. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

改良DuFourmental皮瓣在面部皮肤软组织缺损修复中的应用及疗效

目的探讨改良DuFourmental皮瓣在面部皮肤软组织缺损修复整形术中的应用及效果评价。方法回顾分析22例面部皮肤软组织缺损患者临床资料,缺损直径1～8 cm,均采用DuFourmental皮瓣设计原理并结合面部美容术切口隐蔽的原则加以改良,选择靠近隐蔽区域制作皮瓣,将制作的皮瓣转移至缺损区缝合修复面部创面。结果采用改良的DuFourmental皮瓣封闭创面平整,组织张力小,皮瓣成活良好,部分切口隐蔽效果好。恢复1年后面部瘢痕及切口均不明显,局部外形美观。结论改良DuFourmental皮瓣是修复面部皮肤软组织缺损的一种有效的整形手段,能够保证对面部缺损修复后的美容效果。     

皮肤持续牵张技术联合负压封闭引流技术治疗深度创面的临床观察

目的探讨皮肤持续牵张技术联合负压封闭引流(VSD)技术治疗深度创面的临床疗效。 方法选取2015年5月至2018年5月山西白求恩医院急救医学科收治的不同部位深度创面患者20例,其中外伤10例,压疮7例,感染创面3例。根据创面情况实施清创术后应用皮肤持续牵张联合VSD治疗,观察并记录患者伤口愈合时间,使用温哥华瘢痕量表评估创面愈合质量。 结果20例患者经皮肤持续牵张与VSD治疗后,创面均愈合良好,无愈合不良或不愈合。创面大小为2 cm×2 cm～3 cm×4 cm的5例患者创面平均愈合时间为20 d,创面大小为5 cm×5 cm～8 cm×10 cm的8例患者创面平均愈合时间为22 d,创面大小为10 cm×15 cm～15 cm×20 cm的7例患者创面平均愈合时间为30 d。创面愈合后3个月随访所有患者温哥华瘢痕量表评分平均为3.8分。 结论应用皮肤持续牵张技术与VSD技术联合治疗深度创面不仅可以获得满意的临床效果,而且具有操作简单、创伤小等优点,值得推广。     

The effect of skin grafts on the ratio of collagen types in human post-burn wound tissues

Pepsin digests of human post-burn wound tissues grafted with autologous fresh skin showed a significantly lower ratio, 0.37 +/- 0.04 (mean +/- S.D.), of type III to type I collagen determined by interrupted gel electrophoresis than the ratio, 0.55 +/- 0.13, measured in ungrafted wound tissues (p less than 0.001). In wounds grafted with frozen skin there was no significant difference from ungrafted wounds, but a significantly higher ratio, 0.46 +/- 0.08, than that in wounds grafted with fresh skin (p less than 0.001). These results were consistent with the histological features of the wound tissues.     

Management of sports-induced skin wounds

Skin wounds are common in sports but are rarely documented by the certified athletic trainer. The literature is unclear about wound types, and none of the articles reviewed reported frequencies. The purpose of this paper is to discuss the frequency of common athletic skin wounds and their specific management. Management of skin wounds can sometimes be problematic. Hydrogen peroxide has been used on wounds since 1947, yet some researchers report that hydrogen peroxide and iodophor solution can delay or interfere with wound healing, or cause damage to the wounded area if use is intense and prolonged. Occlusive dressings have been reported to have considerable advantage in maintaining a moist wound bed and in decreasing healing time. Infection rates beneath occlusive dressings, however, are similar to those associated with other types of dressings. Complications to wounds, with or without the use of occlusive dressings, such as keloids and seborrheic dermatitis, occur in low frequencies. Due to a lack of specific information about sports-induced skin wounds and their management, we recommend that standardized documentation for common wounds be developed along with further study of techniques for management.     

Regenerative hypertrophy of the skin in rats

Summary The measurement of the area of the skin located between two wounds on the back of rats and delimited by India ink marks, has demonstrated that with time it increased considerably, in 4 months time constituting 175% of the initial area. Observation of India ink marks made at a definite distance around the wounds demonstrated that the infliction of the wound intensified the growth of the areas of the skin adjacent to the wound. The initial thickness of the growing skin was preserved, and the number of the hair follicle groups was somewhat reduced. The data obtained demonstrated the development of restorative processes of the regenerative hypertrophy type in the skin surrounding the wound.(Presented by Active Member AMN SSSR V. N. Chernigovskii) Translated from Byulleten' eksperimental'noi biologii i meditsiny Vol. 49, No. 1, pp. 99–103, January, 1960