基于X射线相位衬度成像技术的兔眼球血管重建

目的 利用X射线相位衬度成像技术构建兔眼血管网的三维可视化模型,观测兔眼虹膜血管的形态学特征。结果 用硫酸钡对新西兰白兔眼球血管进行造影,利用X射线相位衬度成像技术采集离体兔眼样本的高精度投影图像。图像经由滤波反投影法重建出断层图像,利用Amira 5.2.2软件进行三维重建。方法 高精度投影图像中眼球主干血管清晰连贯,能够观测到部分细小血管的分布及走向,可分辨的最小血管直径约为10 μm;CT扫描图像三维重建后得到兔眼血管网的三维模型,精确到虹膜动脉大环4级分支结构,最小血管直径可达40 μm。结论 利用X射线相位衬度成像技术可以比较清楚地观察到兔眼血管,并且能够在一定程度上构建出血管网的三维可视化模型,为眼球内血管血流动力学分析提供依据,对青光眼的临床研究具有参考价值。     

X射线相位衬度成像的研究进展

在临床医学和材料科学等领域,基于吸收衬度的X射线成像技术是一种非常重要的诊断工具.然而,对于生物医学软组织、聚合物或纤维材料等,由于它们对X射线的弱吸收,这种传统X射线成像技术的应用受到了限制.相位衬度成像是目前X射线成像领域的最新前沿技术和研究热点之一,它能检测对X射线弱吸收的轻元素物质,空间分辨率可达微米甚至亚微米量级,与传统X射线吸收成像技术相比具有独特的优势,并且在医学、生物学、材料科学等领域上获得了成功.介绍了X射线相位衬度成像的原理、成像特点和应用情况.     

裸鼠胃癌模型的相位衬度微血管成像

目的肿瘤血管生成与肿瘤的发生、发展等各个环节密切相关,并显著影响肿瘤的生物学行为和预后。本研究的目的在于使用相位衬度成像技术三维地、全面地观察肿瘤微血管形态。方法使用原位接种肿瘤组织块方法,建立裸鼠胃癌原位模型。实验样本分为正常组和肿瘤组。对得到的相位衬度图像进行增强、血管分割、三维重建,并且计算三维微血管密度参数。结果相位衬度成像可显示胃癌组织的微血管形态。对照组微血管密度低于胃癌组的肿瘤表面区域(P0.001),证明肿瘤微血管更加丰富。结论相位衬度成像可以更全面地显示肿瘤微血管的生成情况,有助于对胃癌的恶性程度、转移潜力等进行评估,并对治疗方案的选择、判断预后和评估抗肿瘤血管药物疗效具有重要意义。     

同步辐射在医学成像中的应用综述

同步辐射(synchrotron radiation,SR)作为一种具有优良特性的新型光源已引起大家的广泛关注,几乎成为多学科公用的一个先进的、不可替代的综合科技平台,尤其在医学成像方面,更是表现出强劲的生命力.本文拟从同步辐射血管造影、支气管成像、断层显像、相位衬度显像等多面阐述同步辐射在医学成像中的应用.     

基于同轴相衬成像方法的人体膝关节软骨可视化

目的同轴相位衬度成像对软组织具有高衬度和高分辨率的特性。利用该成像技术,通过纹理特征参数提取进行定量分析,可为骨性关节炎的早期诊断提供可行性的依据。方法研究样本来自人工关节置换手术患者的膝关节软骨。样本分为正常组与早期骨性关节炎(osteoarthritis,OA)组,每组18例膝关节软骨组织。利用同轴相衬成像(in-line phase contrast imaging,IL-PCI)技术,观察两组软骨组织的纹理差异,并运用行程长度矩阵与分形维数方法提取纹理特征参数长行程加重(long run emphasis,LRE)、短行程加重(short run emphasis,SRE)、程分数(run percentage,RP)、灰度级的非均匀性(gray level non-uniformity,GLN)、行程长度的非均匀性(run length non-uniformity,RLN)以及分形维数。通过独立样本t检验方法比较上述参数,量化分析正常与病变软骨组织纹理差异。结果利用IL-PCI技术可以清晰观察到正常与早期OA软骨中微结构的变化。通过纹理参数提取比较两组的软骨纹理特征,结果表明正常组的LRE明显高于早期OA组(P<0.01),而早期OA组的GLN、RLN远高于正常组(P<0.01),正常组的分形维数小于早期OA组(P<0.01)。结论同轴相衬技术可为骨性关节炎的早期诊断提供定量分析手段。     

基于MITK的医学影像三维可视化研究

利用MITK在VC6.0环境下编程实现对多组医学图像数据的三维可视化,通过对实际数据和不同算法的面绘制、体绘制、分割和配准等多方面的研究,考察了MITK在医学图像处理和三维可视化领域的实用性.结果 表明MITK编程实现较容易,成像速度快,效果好,针对医学影像处理有其独特的优势.MITK作为一种医学图像处理和三维可视化的工具,功能十分强大,完全可以与现有的同类软件包相媲美.     

同步辐射光源相衬成像技术在形态学研究中的应用

目的探讨同步辐射相位衬度成像在形态学研究中的应用前景。方法以北京同步辐射装置（BSRF）4W1A束线提供的硬X线,采用衍射增强成像（DEI）和类同轴成像法对经10％福尔马林固定的正常猪、大鼠、小鼠的肝、肾、肺、骨等组织进行成像,并与成像样品的相邻组织及成像后原位组织切片的光镜染色结果进行对比分析。结果衍射增强成像显示大鼠肝脏血管的逐级分支,走行方向清楚,最细可分辨直径为30μm的血管;猪肝脏中央静脉、肝小叶分界隐约可见;大鼠肾脏皮、髓质分界清楚,弓形动脉、静脉及髓质区集合管、乳头管结构清晰可见,最细可分辨直径为30μm的管道结构;小鼠肺支气管树分支清楚,重叠肺泡隐约可见。类同轴成像大鼠股骨头关节软骨及骨小梁结构清楚。结论利用同步辐射相位衬度成像方法,样品无需制片处理即可观察到光镜及其他影像学技术尚不能直接观察到的脉管系统模式结构及其与周围组织的结构关系,此外还可以观察到常规X线成像方法无法观察到的软骨影像,比较适合形态学研究。     

肺癌肺内肿瘤三维适形放疗正常肺组织定义的研究

目的:分析肺癌肺内肿瘤三维适形放疗中各种正常肺体积定义,探讨合理的正常肺体积定义方法。方法:肺癌肺内病变患者CT定位,扫描范围包括全肺,将数据传输到治疗计划系统(TPS),勾画肿瘤靶区(GTV)、临床靶区(CTV)、计划靶区(PTV)。将PTV外所有具备正常肺功能的肺组织定义为正常肺组织,设计制定计划一(P1);将GTV外所有具备正常肺功能的肺组织定义为正常肺组织,设计制定计划二(P2);将全肺组织定义为正常肺组织,设计制定计划三(P3)。P1、P2、P3的射野数、射野方向、权重,剂量分布等相同。利用剂量体积直方图(DVH),分析比较三个计划的V20、V30、Dmean等值。结果:P3的V20、V30、Dmean等比P2的稍大,均数没有显性差异(P﹥0.05);P1的V20、V30、Dmean等比P2的小,均数均有差异(P﹤0.05)。结论:P1掩盖了肺体积的损伤,尤其是肿瘤体积大时更为突出,容易产生严重肺损伤。P2反映了客观情况,可以引起医生高度警惕,避免严重肺损伤发生,建议将GTV外所有具备正常肺功能的肺组织定义为正常肺组织。     

三维可视化技术在复杂骨与软组织肿瘤手术中的临床应用

目的:探讨三维可视化技术在复杂骨与软组织肿瘤外科手术治疗中的临床应用价值。方法:回顾性研究。纳入2019年4—12月中国科学技术大学附属第一医院(西区)骨科11例复杂骨与软组织肿瘤患者的临床资料,其中男5例、女6例,年龄16～67(52.6±15.9)岁。11例患者术前均行CT常规二维扫描及三维可视化技术重建,于重建模...     

基于散斑衬比算法的高频超声血流成像技术研究

目的 探讨激光散斑衬比算法在高频超声血流成像技术中的应用。 方法 将激光散斑衬比算法拓展到高频超声血流成像领域,利用经典的激光散斑时间衬比算法对高频超声结构图像进行处理,静态组织信号得到抑制,动态血流信号信息得到加强,获得高频超声血流图像。对微血流仿体进行仿真实验,验证算法的有效性。进行人体皮肤组织活体实验,验证算法的可应用性,对不同帧数的超声结构图像进行激光散斑衬比算法处理,对比分析超声血流图像质量。 结果 微血流仿体仿真实验结果表明,管内血流信息清晰可见。人体皮肤组织活体实验结果表明,静态皮肤组织信号得到明显抑制,动态血流信号得到加强,获得清晰高频超声血流图像。通过对不同帧数超声结构图象得到的血流图像分析,图像处理帧数设为10帧时具有最佳的图像显示效果。 结论 激光散斑衬比算法可以应用于高频超声血流成像,具有良好的应用前景。     

High-resolution visualization of airspace structures in intact mice via synchrotron phase-contrast X-ray imaging (PCXI)

Anatomical visualization of airspace-containing organs in intact small animals has been limited by the resolution and contrast available from current imaging methods such as X-ray, micro-computed tomography and magnetic resonance imaging. Determining structural relationships and detailed anatomy has therefore relied on suitable fixation, sectioning and histological processing. More complex and informative analyses such as orthogonal views of an organ and three-dimensional structure visualizations have required different animals and image sets, laboriously processed to gather this complementary structural information. Precise three-dimensional anatomical views have always been difficult to achieve in small animals. Here we report the ability of phase-contrast synchrotron X-ray imaging to provide detailed two- and three-dimensional visualization of airspace organ structures in intact animals. Using sub-micrometre square pixel charge-coupled device array detectors, the structure and anatomy of hard and soft tissues, and of airspaces, is readily available using phase-contrast synchrotron X-ray imaging. Moreover, software-controlled volume-reconstructions of tomographic images not only provide unsurpassed image clarity and detail, but also selectable anatomical views that cannot be obtained with established histological techniques. The morphology and structure of nasal and lung airways and the middle ear are illustrated in intact mice, using two- and three-dimensional representations. The utility of phase-contrast synchrotron X-ray imaging for non-invasively localizing objects implanted within airspaces, and the detection of gas bubbles transiting live airways, are other novel features of this visualization methodology. The coupling of phase-contrast synchrotron X-ray imaging technology with software-based reconstruction techniques holds promise for novel and high-resolution non-invasive examination of airspace anatomy in small animal models.     

Multi-generational analysis and visualization of the vascular tree in 3D micro-CT images

Micro-CT scanners can generate large high-resolution three-dimensional (3D) digital images of small-animal organs, such as rat hearts. Such images enable studies of basic physiologic questions on coronary branching geometry and fluid transport. Performing such an analysis requires three steps: (1) extract the arterial tree from the image; (2) compute quantitative geometric data from the extracted tree; and (3) perform a numerical analysis of the computed data. Because a typical coronary arterial tree consists of hundreds of branches and many generations, it is impractical to perform such an integrated study manually. An automatic method exists for performing step (1), extracting the tree, but little effort has been made on the other two steps. We propose an environment for performing a complete study. Quantitative measures for arterial-lumen cross-sectional area, inter-branch segment length, branch surface area and others at the generation, inter-branch, and intra-branch levels are computed. A human user can then work with the quantitative data in an interactive visualization system. The system provides various forms of viewing and permits interactive tree editing for "on the fly" correction of the quantitative data. We illustrate the methodology for 3D micro-CT rat heart images.     

3-D visualization and animation technologies in anatomical imaging

This paper explores a 3‐D computer artist’s approach to the creation of three‐dimensional computer‐generated imagery (CGI) derived from clinical scan data. Interpretation of scientific imagery, such as magnetic resonance imaging (MRI), is restricted to the eye of the trained medical practitioner in a clinical or scientific context. In the research work described here, MRI data are visualized and interpreted by a 3‐D computer artist using the tools of the digital animator to navigate image complexity and widen interaction. In this process, the artefact moves across disciplines; it is no longer tethered to its diagnostic origins. It becomes an object that has visual attributes such as light, texture and composition, and a visual aesthetic of its own. The introduction of these visual attributes provides a platform for improved accessibility by a lay audience. The paper argues that this more artisan approach to clinical data visualization has a potential real‐world application as a communicative tool for clinicians and patients during consultation.     

3D可视化联合3D打印在肝癌大部分肝切除术中的应用

目的:探讨基于3D重建系统软件的肝体积评估和3D可视化、3D打印辅助肝癌大部分肝切除术的应用价值。方法:将符合要求的肝癌行大部分肝切除术患者46例,随机分为观察组和对照组,每组23例。观察组（3D组）患者采用3D可视化技术和3D打印模型进行围手术期规划和指导,主要基于肝体积评估等术前规划和3D可视化分析、3D打印指导肝切除术手术;对照组（CT组）患者采用传统CT资料进行肝体积评估等术前规划、CT二维影像资料指导肝切除术。观察指标:虚拟切除肝体积、实际切除肝体积、残肝体积、标准残肝体积比、手术时间、术中出血量、术后并发症、患者满意度等。结果:3D组与CT组虚拟切除肝体积与实际切除肝体积、虚拟（术前）残肝体积与实际（术后）残肝体积比较,差异均无统计学意义（P>0.05）,相关性分析显示虚拟切除肝体积与实际切除肝体积呈正相关性（3D组r=0.990, P<0.001;CT组r=0.943, P<0.001）。3D组与CT组虚拟残肝体积比、实际残肝体积比比较,差异均无统计学意义（P>0.05）,且相关性分析显示呈正相关性（3D组r=0.931, P<0.001;CT组r=0.902, P<0.001)。3D组术中出血量少于CT组（P<0.05）,3D组患者满意度优于CT组（P<0.05）。两组患者手术时间、术后并发症等比较,差异无统计学意义（P>0.05）。结论:3D重建系统软件和CT软件在评估肝癌大部分肝切除术的肝体积均可行、准确,具有很好的临床应用价值,有助于肝切除术的安全实施。3D可视化联合3D打印在围手术规划可减少手术出血,提高患者满意度,在临床应用中具有潜在优势。     

3D visualization as a communicative aid in pharmaceutical advice-giving over distance

Background

Medication misuse results in considerable problems for both patient and society. It is a complex problem with many contributing factors, including timely access to product information.

Objective

To investigate the value of 3-dimensional (3D) visualization paired with video conferencing as a tool for pharmaceutical advice over distance in terms of accessibility and ease of use for the advice seeker.

Methods

We created a Web-based communication service called AssistancePlus that allows an advisor to demonstrate the physical handling of a complex pharmaceutical product to an advice seeker with the aid of 3D visualization and audio/video conferencing. AssistancePlus was tested in 2 separate user studies performed in a usability lab, under realistic settings and emulating a real usage situation. In the first study, 10 pharmacy students were assisted by 2 advisors from the Swedish National Co-operation of Pharmacies’ call centre on the use of an asthma inhaler. The student-advisor interview sessions were filmed on video to qualitatively explore their experience of giving and receiving advice with the aid of 3D visualization. In the second study, 3 advisors from the same call centre instructed 23 participants recruited from the general public on the use of 2 products: (1) an insulin injection pen, and (2) a growth hormone injection syringe. First, participants received advice on one product in an audio-recorded telephone call and for the other product in a video-recorded AssistancePlus session (product order balanced). In conjunction with the AssistancePlus session, participants answered a questionnaire regarding accessibility, perceived expressiveness, and general usefulness of 3D visualization for advice-giving over distance compared with the telephone and were given a short interview focusing on their experience of the 3D features.

Results

In both studies, participants found the AssistancePlus service helpful in providing clear and exact instructions. In the second study, directly comparing AssistancePlus and the telephone, AssistancePlus was judged positively for ease of communication (P = .001), personal contact (P = .001), explanatory power (P < .001), and efficiency (P < .001). Participants in both studies said that they would welcome this type of service as an alternative to the telephone and to face-to-face interaction when a physical meeting is not possible or not convenient. However, although AssistancePlus was considered as easy to use as the telephone, they would choose AssistancePlus over the telephone only when the complexity of the question demanded the higher level of expressiveness it offers. For simpler questions, a simpler service was preferred.

Conclusions

3D visualization paired with video conferencing can be useful for advice-giving over distance, specifically for issues that require a higher level of communicative expressiveness than the telephone can offer. 3D-supported advice-giving can increase the range of issues that can be handled over distance and thus improve access to product information.     

Synchrotron phase-contrast imaging applied to the anatomical study of the hand and its vascularization

Microscopic anatomical study of the hand requires difficult or destructive dissection techniques for each anatomical structure. Synchrotron phase-contrast imaging (sPCI) allows us to study precisely, at a microscopic resolution and in a nondestructive approach, the soft tissues and bone structures within a single 3D image. Therefore, we aimed to assess the capacity of sPCI to study the arterial anatomy of the hand and digits in human cadavers for anatomical purposes. A non-injected hand from an embalmed body was imaged using sPCI at 21-µm pixel size. The vascularization and innervation of the hands were virtually reconstructed at 84-µm resolution, and the medial neurovascular bundle of the third digit at 21 µm. The thinner-most distal structures were observed and reported. The diameter and thickness of the vascular and neural structures were defined on 2D computed tomographic axial projections, and using a granulometry method coupled to the 3D reconstructions. The vascularization of the hand was visible from the radial and ulnar arteries to the distal digital transverse anastomoses. The thinnest structure observed was the anastomotic arterial network around the proper palmar digital nerve. The latter emerged from the proper palmar digital artery and vascularized the nerve around its whole length and circumference. The perineural arterioles individualizable at this resolution had a diameter of 66–309 µm. In conclusion, sPCI allows both the arterial and neural anatomy of the hand to be studied at the same time, as well as the anatomical interactions between both networks. It facilitates the study of structures that have different sizes, diameters, thickness, and histological origin with great precision, in a noninvasive way, and using a single technique.     

数字化原位子宫动脉血管3D可视化模型的构建及意义

目的探讨构建女性原位子宫动脉血管3D可视化模型和研究子宫动脉血管的结构特征。方法采用聚乙烯醇-氧化铈血管造影术进行2例女尸盆腔动脉血管灌注,X线平位摄影、64排螺旋CT扫描后采集数据,导入计算机Mimics10.01重建软件进行子宫动脉血管3D可视化模型构建,观察子宫动脉血管的形态及血供分布情况。结果①构建的子宫动脉血管三维模型图像清晰,管道饱满,立体空间感强,均能清晰地显示子宫动脉的4级以上血管,各级分支血管的形态、走行、分布及各血管间的吻合显影清晰,效果满意。2例子宫及附件无实质性病变,为正常子宫。②清晰显示子宫动脉血管网的构建特点:子宫动脉自主干依次发出膀胱支、输尿管支、上行支、下行支等分支动脉;上行支较粗呈弓状沿子宫体侧缘迂曲上行,至宫角处分为宫底支、输卵管支和卵巢支,主要向子宫体和子宫附件供血;下行支较细分布于宫颈及阴道上段,但分布于阴道的血管较少;子宫动脉通过其卵巢支与卵巢动脉相交通;同时子宫动脉的供血还存有着明显的同侧倾向,双侧子宫动脉在子宫的中轴线处有少量细小的交通支。结论采用聚乙烯醇-氧化铈血管造影术盆腔动脉血管灌注可构建理想的子宫动脉血管网3D可视化模型,为系统研究人子宫动脉血管网的形态结构和血供分布提供了血管解剖学基础。     

胰十二指肠区动脉血管3D可视化模型的构建及意义

目的探讨构建胰十二指肠区动脉血管3D可视化模型和研究胰十二指肠区动脉血管的结构特征。方法采用128排螺旋CT对5例新鲜肝标本进行扫描,并进行三维重建。记录螺旋CT影像下胰十二指肠区血管的空间位置关系。结果构建的胰十二指肠区动脉血管三维模型图像清晰,管道饱满,立体空间感强,均能清晰地显示胰十二指肠区动脉的4级以上血管,各级分支血管的形态、走行、分布及各血管间的吻合显影清晰,效果满意。清晰显示胰十二指肠区动脉血管网的构建特点。结论采用聚乙烯醇-氧化铈血管造影术胰十二指肠区动脉血管灌注可构建理想的胰十二指肠区动脉血管网3D可视化模型,为系统研究人胰十二指肠区动脉血管网的形态结构和血供分布提供了血管解剖学基础。     

System for the analysis and visualization of large 3D anatomical trees

Modern micro-CT and multi-detector helical CT scanners can produce high-resolution 3D digital images of various anatomical trees. The large size and complexity of these trees make it essentially impossible to define them interactively. Automatic approaches have been proposed for a few specific problems, but none of these approaches guarantee extracting geometrically accurate multi-generational tree structures. This paper proposes an interactive system for defining and visualizing large anatomical trees and for subsequent quantitative data mining. The system consists of a large number of tools for automatic image analysis, semi-automatic and interactive tree editing, and an assortment of visualization tools. Results are presented for a variety of 3D high-resolution images.     

医学影像数据与3D打印技术

随着新材料和新技术的不断发展,影像学数据和3D打印技术之间的联系越来越紧密。采集影像数据并进行三维数字化建模是实现医学3D打印的基础。本文综述了3D打印技术及基于影像学数据所生成的三维模型在临床领域的应用。最后,对影像学技术和3D打印技术在未来的发展前景做了简要论述。