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1.
This paper explores brain CT slices segmentation technique and some related problems, including contours segmentation algorithms, edge detector, algorithm evaluation and experimental results. This article describes a method for contour-based segmentation of anatomical structures in 3D medical data sets. With this method, the user manually traces one or more 2D contours of an anatomical structure of interest on parallel planes arbitrarily cutting the data set. The experimental results showed the segmentation based on 3D brain volume and 2D CT slices. The main creative contributions in this paper are: (1) contours segmentation algorithm; (2) edge detector; (3) algorithm evaluation. Project (No.69931010) supported by the National Natural Science Foundation of China  相似文献   

2.
INTRODUCTIONSegmentation ,acentralissueofcomputervision ,isafundamentalprocessingstepinmostsystemsthatsupportmedicaldiagnosisorplan ningofsurgicaloperationsandradiationtreat ments (Wyattetal.,2 0 0 0 ;Wintereretal.,2 0 0 2 ;Baoetal.,1998) .Contour basedse…  相似文献   

3.
Tomographic particle image velocimetry(Tomo-PIV) is a state-of-the-art experimental technique based on a method of optical tomography to achieve the three-dimensional(3D) reconstruction for threedimensional three-component(3D-3C) flow velocity measurements. 3D reconstruction for Tomo-PIV is carried out herein. Meanwhile, a 3D simplified tomographic reconstruction model reduced from a 3D volume light intensity field with 2D projection images into a 2D Tomo-slice plane with 1D projecting lines, i.e., simplifying this 3D reconstruction into a problem of 2D Tomo-slice plane reconstruction, is applied thereafter. Two kinds of the most well-known algebraic reconstruction techniques, algebraic reconstruction technique(ART) and multiple algebraic reconstruction technique(MART), are compared as well. The principles of the two reconstruction algorithms are discussed in detail, which has been performed by a series of simulation images, yielding the corresponding reconstruction images that show different features between the ART and MART algorithm, and then their advantages and disadvantages are discussed. Further discussions are made for the standard particle image reconstruction when the background noise of the pre-initial particle image has been removed. Results show that the particle image reconstruction has been greatly improved. The MART algorithm is much better than the ART. Furthermore, the computational analyses of two parameters(the particle density and the number of cameras), are performed to study their effects on the reconstruction. Lastly, the 3D volume particle field is reconstructed by using the improved algorithm based on the simplified 3D tomographic reconstruction model, which proves that the algorithm simplification is feasible and it can be applied to the reconstruction of 3D volume particle field in a Tomo-PIV system.  相似文献   

4.
Understanding the three‐dimensional (3D) nature of the human form is imperative for effective medical practice and the emergence of 3D printing creates numerous opportunities to enhance aspects of medical and healthcare training. A recently deceased, un‐embalmed donor was scanned through high‐resolution computed tomography. The scan data underwent segmentation and post‐processing and a range of 3D‐printed anatomical models were produced. A four‐stage mixed‐methods study was conducted to evaluate the educational value of the models in a medical program. (1) A quantitative pre/post‐test to assess change in learner knowledge following 3D‐printed model usage in a small group tutorial; (2) student focus group (3) a qualitative student questionnaire regarding personal student model usage (4) teaching faculty evaluation. The use of 3D‐printed models in small‐group anatomy teaching session resulted in a significant increase in knowledge (P = 0.0001) when compared to didactic 2D‐image based teaching methods. Student focus groups yielded six key themes regarding the use of 3D‐printed anatomical models: model properties, teaching integration, resource integration, assessment, clinical imaging, and pathology and anatomical variation. Questionnaires detailed how students used the models in the home environment and integrated them with anatomical learning resources such as textbooks and anatomy lectures. In conclusion, 3D‐printed anatomical models can be successfully produced from the CT data set of a recently deceased donor. These models can be used in anatomy education as a teaching tool in their own right, as well as a method for augmenting the curriculum and complementing established learning modalities, such as dissection‐based teaching. Anat Sci Educ 11: 44–53. © 2017 American Association of Anatomists.  相似文献   

5.
人体三维几何建模及其可视化显示是生物医学学科的一项基础性研究。CT和MRI等医学成像技术的断层图像可为三维建模提供基础。章论述和介绍了基于CT、MRI断层图像的三维建模系统的关键技术和相关实现原理。  相似文献   

6.
双目定位跟踪系统涉及到的关键技术有摄像机标定、立体匹配和三维重建等.在三维重建阶段,利用匹配的结果采用最小二乘法计算定位标靶上标记的三维坐标.实验结果表明,在现有条件下,双目定位跟踪系统的定位精度比较高,相对误差在1%以内;基于此定位跟踪系统,能够初步准确完成对经络的三维定位和实时显示,为临床诊断治疗和基础教学提供直观的分析依据.  相似文献   

7.
提出在商业以及教育领域的多媒体演示中对于实现实时三维交互的迫切需要性,在解决此类问题时VRML技术的缺点以及Cult3D技术的优点,并通过实例说明了如何在Authorware中通过对于ActiveX组件的调用解决多媒体作品中实时操控三维模型的问题,简述了Cult3D网络元文件的生成过程.  相似文献   

8.
以焦炉为例,介绍了一种复杂设备的三维结构交互式演示系统开发方法。应用SketchUp建立焦炉各组成部分的三维数字模型,并导出展示其内部结构的图片和动画。应用Authorware制作焦炉结构三维交互演示系统,该演示系统能用大量的三维图像和动画生动形象地展示焦炉各大组成部分的内部结构和基本工作原理。  相似文献   

9.
High-fidelity anatomical models can be produced with three-dimensional (3D) scanning techniques and as such be digitally preserved, archived, and subsequently rendered through various media. Here, a novel methodology—digital body preservation—is presented for combining and matching scan geometry with radiographic imaging. The technique encompasses joining layers of 3D surface scans in an anatomical correct spatial relationship. To do so, a computed tomography (CT) volume is used as template to join and merge different surface scan geometries by means of nonrigid registration into a single environment. In addition, the use and applicability of the generated 3D models in digital learning modalities is presented. Finally, as computational expense is usually the main bottleneck in extended 3D applications, the influence of mesh simplification in combination with texture mapping on the quality of 3D models was investigated. The physical fidelity of the simplified meshes was evaluated in relation to their resolution and with respect to key anatomical features. Large- and medium-scale features were well preserved despite extensive 3D mesh simplification. Subtle fine-scale features, particular in curved areas demonstrated the major limitation to extensive mesh size reduction. Depending on the local topography, workable mesh sizes ranging from 10% to 3% of the original size could be obtained, making them usable in various learning applications and environments.  相似文献   

10.
利用VTK可视化工具包在Visual Studio2008平台上实现了医学序列图像三维的可视化.在对三维数据的预处理和优化基础上,在MFC实现的可交互界面上,用Marching Cubes(立方体移动)算法和Ray—casting(光线投射)算法对DICOM等格式的切片进行三维重建.  相似文献   

11.
人体切片数据的三维重建系统设计   总被引:2,自引:0,他引:2  
阐述了利用人体切片数据,从二维图像中提取三维信息,并采用OpenGL开发工具进行三维重建的方法。根据不同点云绘制方法与计算消耗时间的关系,重点提出如何结合点云绘制与网格绘制,有效、快速的实现了人体切片数据的三维重建。  相似文献   

12.
为了在三维超声成像中获得更多、更详细的位置信息,得到更准确的定位精度,采用机械臂夹持超声探头并利用L-M算法进行超声图像标定。标定过程中,通过将N线模板放在水槽中,从而得到更准确的定位装置接收器与超声图像之间的位置转换关系,利用六自由度机械臂控制超声探头水平移动扫描模板以获取超声图像,并利用区域提取与缺陷分割技术获得图像中的像素坐标,以及扫描点在模板中对应的实际坐标,最后运用L-M算法进行标定计算,获得所需的标定转换矩阵。实验结果证明,该方法简单易行且效率较高,提高了标定精度,可满足实际检测精度需求,避免了手动扫描误差,为后续三维重建奠定了基础。  相似文献   

13.
The practical aspect of human developmental biology education is often limited to the observation and use of animal models to illustrate developmental anatomy. This is due in part to the difficulty of accessing human embryonic and fetal specimens, and the sensitivity inherent to presenting these specimens as teaching materials. This report presents a new approach using three-dimensional (3D) printed replicas of actual human materials in practical classes, thus allowing for the inclusion of accurate examples of human developmental anatomy in the educational context. A series of 3D prints have been produced from digital data collected by computed tomography (CT) imaging of an archived series of preserved human embryonic and fetal specimens. The final versions of 3D prints have been generated in a range of single or multiple materials to illustrate the progression of human development, including the development of internal anatomy. Furthermore, multiple copies of each replica have been printed for large group teaching. In addition to the educational benefit of examining accurate 3D replicas, this approach lessens the potential for adverse student reaction (due to cultural background or personal experience) to observing actual human embryonic/fetal anatomical specimens, and reduces the potential of damage or loss of original specimens. This approach, in combination with ongoing improvements in the management and analysis of digital data and advances in scanning technology, has enormous potential to allow embryology students access to both local and international collections of human gestational material. Anat Sci Educ 00: 000–000. © 2018 American Association of Anatomists.  相似文献   

14.
INTRODUCTION The visualization of roadside buildings in virtual space using synthetic photorealistic view is one of the common methods for representing the background scene of Car Navigation Systems (CNS) and Internet map services. Since most of these background scenes are implemented by two-dimensional (2D) images, they may give somewhat monotonous impression due to fixed viewpoint position and orientation. For more interactive visualizations that enable arbitrary ad- justment of the …  相似文献   

15.
Advances in three‐dimensional (3D) printing allow for digital files to be turned into a “printed” physical product. For example, complex anatomical models derived from clinical or pre‐clinical X‐ray computed tomography (CT) data of patients or research specimens can be constructed using various printable materials. Although 3D printing has the potential to advance learning, many academic programs have been slow to adopt its use in the classroom despite increased availability of the equipment and digital databases already established for educational use. Herein, a protocol is reported for the production of enlarged bone core and accurate representation of human sinus passages in a 3D printed format using entirely consumer‐grade printers and a combination of free‐software platforms. The comparative resolutions of three surface rendering programs were also determined using the sinuses, a human body, and a human wrist data files to compare the abilities of different software available for surface map generation of biomedical data. Data shows that 3D Slicer provided highest compatibility and surface resolution for anatomical 3D printing. Generated surface maps were then 3D printed via fused deposition modeling (FDM printing). In conclusion, a methodological approach that explains the production of anatomical models using entirely consumer‐grade, fused deposition modeling machines, and a combination of free software platforms is presented in this report. The methods outlined will facilitate the incorporation of 3D printed anatomical models in the classroom. Anat Sci Educ 10: 383–391. © 2017 American Association of Anatomists.  相似文献   

16.
Three-dimensional (3D) printing technology has become more affordable, accessible, and relevant in healthcare, however, the knowledge of transforming medical images to physical prints still requires some level of training. Anatomy educators can play a pivotal role in introducing learners to 3D printing due to the spatial context inherent to learning anatomy. To bridge this knowledge gap and decrease the intimidation associated with learning 3D printing technology, an elective was developed through a collaboration between the Department of Anatomy and the Makers Lab at the University of California, San Francisco. A self-directed digital resource was created for the elective to guide learners through the 3D printing workflow, which begins with a patient's computed tomography digital imaging and communication in medicine (DICOM) file to a physical 3D printed model. In addition to practicing the 3D printing workflow during the elective, a series of guest speakers presented on 3D printing applications they utilize in their clinical practice and/or research laboratories. Student evaluations indicated that their intimidation associated with 3D printing decreased, the clinical and research topics were directly applicable to their intended careers, and they enjoyed the autonomy associated with the elective format. The elective and the associated digital resource provided students with the foundational knowledge of 3D printing, including the ability to extract, edit, manipulate, and 3D print from DICOM files, making 3D printing more accessible. The aim of disseminating this work is to help other anatomy educators adopt this curriculum at their institution.  相似文献   

17.
为了满足生物医学工程专业实践课程教学需求,通过引入三维设计软件,创造性地开发医疗器械结构相关原理讲解、机构运动简图绘制、三维建模设计、虚拟样机装配、运动仿真、力学动力学分析等综合实验、课程设计实践教学项目,将医疗器械专业知识与计算机软件辅助设计相结合,构建生物医学工程专业虚实结合的新实践教学模式。实践探索表明,将三维软件应用于生物医学工程实践教学,改变了抽象的结构讲解方式,降低了学习难度,提高了学生学习兴趣和效率。  相似文献   

18.
三维成像技术是计算机图形学的一个重要研究方向,在现代临床医学及工业等各方面都有重要的应用。本文介绍了由二维图像序列生成三维图像的重建算法和显示方法;并介绍了如何在Visual C 6.0环境下,由上述算法开发出基于OpenGL的相应程序。  相似文献   

19.
Despite a long tradition, conventional anatomy education based on dissection is declining. This study tested a new virtual reality (VR) technique for anatomy learning based on virtual contrast injection. The aim was to assess whether students value this new three‐dimensional (3D) visualization method as a learning tool and what value they gain from its use in reaching their anatomical learning objectives. Several 3D vascular VR models were created using an interactive segmentation tool based on the “virtual contrast injection” method. This method allows users, with relative ease, to convert computer tomography or magnetic resonance images into vivid 3D VR movies using the OsiriX software equipped with the CMIV CTA plug‐in. Once created using the segmentation tool, the image series were exported in Quick Time Virtual Reality (QTVR) format and integrated within a web framework of the Educational Virtual Anatomy (EVA) program. A total of nine QTVR movies were produced encompassing most of the major arteries of the body. These movies were supplemented with associated information, color keys, and notes. The results indicate that, in general, students' attitudes towards the EVA‐program were positive when compared with anatomy textbooks, but results were not the same with dissections. Additionally, knowledge tests suggest a potentially beneficial effect on learning. Anat Sci Ed 2:61–68, 2009. © 2009 American Association of Anatomists.  相似文献   

20.
本文采用JAVA3D语言,对三维空间表面上的数据进行直观地可视化显示,显示的结果是交互式的,可以改变观测角度及任意缩放,本文通过一个具体模型,说明了该方法的可行性,并给出了具体实施过程及相应的具体程序。  相似文献   

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