医学图像可视化及加速技术的研究进展和趋势****☆

摘要：近年来图像可视化技术蓬勃发展,相应的各种加速算法也层出不穷,本文将尝试就此内容进行综述和概括。首先介绍可视化技术的两大分支——面绘制和体绘制的含义和主要特点;其次详细介绍体绘制技术中一些典型算法的基本原理及各自特点;然后分别从软件和硬件角度归纳体绘制技术中常用的加速技术;最后展望医学图像可视化及加速技术的发展趋势。     

A Functional Map of Cervical Metastases from Oral Squamous Cell Carcinoma

A visual summary of underlying patterns in metastases from oral squamous cell carcinoma (SCC) was created by the mathematical technique of multidimensional scaling (MDS). MDS creates a "functional" map of the neck, such that adjacent sites share similar probabilities of disease. We mapped the metastases from 130 sequential cases of oral SCC in the UK. Binary Euclidean distances were calculated from tallies of metastases at all possible pairs of neck levels (I-V on each side) for each of seven different primary sites: buccal mucosa, lower alveolus, floor of mouth, ventral tongue/floor of mouth, lateral tongue, retromolar trigone, and oropharynx. A two-dimensional functional map of the neck was made from these distances. The map explains 82% of the input data (p < 0.01). This is the first functional mapping of neck levels. The technique can now be used to summarize and compare patterns of metastases in different populations.     

The disembodied eye: Consequences of displacing perception from action

In our research, people use actions to expose hidden targets as planar images displayed either in situ or ex situ (displaced remotely). We show that because ex situ viewing impedes relating actions to their perceptual consequences, it impairs localizing targets, including compensating for surface deformation, and directing movement toward them. Using a 3D analogue of anorthoscopic perception, we demonstrate that spatio-temporal integration of contiguous planar slices is possible when action and perception are co-located, but not when they are separated. Ex situ viewing precludes the formation of a spatial frame of reference that supports complex visualization from action.     

基于百度地图的钉螺监测系统的实现

目的基于百度地图构建钉螺监测系统。方法收集历史有螺、现有螺等钉螺监测环境基础信息及各类钉螺监测数据,建立钉螺监测数据库,利用地理信息系统(Geographic Information System,GIS)电子围栏技术及百度地图开发者接口(Application Program Interface,API)完成各钉螺监测环境的电子围栏设定,并完成电子围栏同钉螺监测数据库的关联。结果基于百度地图建立了钉螺监测系统。该系统包含"钉螺监测环境数据库"、"动态监测端"、"电子地图展示"3个模块。通过PC端、智能手机端,均可在百度地图上查看钉螺监测信息。结论基于百度地图开发的钉螺监测系统,可以作为查、灭螺等钉螺监测资料数字化、动态化管理的工具,以及可视化展现的平台。     

Four-dimensional flow magnetic resonance imaging in cirrhosis

Since its introduction in the 1970’s, magnetic resonance imaging (MRI) has become a standard imaging modality. With its broad and standardized application, it is firmly established in the clinical routine and an essential element in cardiovascular and abdominal imaging. In addition to sonography and computer tomography, MRI is a valuable tool for diagnosing cardiovascular and abdominal diseases, for determining disease severity, and for assessing therapeutic success. MRI techniques have improved over the last few decades, revealing not just morphologic information, but functional information about perfusion, diffusion and hemodynamics as well. Four-dimensional (4D) flow MRI, a time-resolved phase contrast-MRI with three-dimensional (3D) anatomic coverage and velocity encoding along all three flow directions has been used to comprehensively assess complex cardiovascular hemodynamics in multiple regions of the body. The technique enables visualization of 3D blood flow patterns and retrospective quantification of blood flow parameters in a region of interest. Over the last few years, 4D flow MRI has been increasingly performed in the abdominal region. By applying different acceleration techniques, taking 4D flow MRI measurements has dropped to a reasonable scanning time of 8 to 12 min. These new developments have encouraged a growing number of patient studies in the literature validating the technique’s potential for enhanced evaluation of blood flow parameters within the liver’s complex vascular system. The purpose of this review article is to broaden our understanding of 4D flow MRI for the assessment of liver hemodynamics by providing insights into acquisition, data analysis, visualization and quantification. Furthermore, in this article we highlight its development, focussing on the clinical application of the technique.     

正颌外科三维立体可视化模拟手术研究

目的：建立基于CT图像数据的计算机辅助三维立体手术模拟系统，为了术前进行精确设计手术方案及达到术后良好效果提供真实可靠依据。方法：应用医学可视化技术和Visual C^**编程语言开发出立体结构三维重建和手术模拟软件，建立以CT数据为信息源的计算机正颌外科立体可视化手术仿真模拟系统，可模拟各种正颌外科手术移动骨质过程，并且以动态动画形式演示，可从任意角度进行观察。结果：该系统建立了颅颌面畸形立体结构模型，以动态形式成功演示了正颌外科截骨移动手术仿真模拟，手术过程真实逼真，立体可视化效果好，应用普通播放软件即可在计算机屏幕上播放模拟正颌外科手术过程，并可预测手术后上下颌咬合状态及手术效果。结论：正颌外科三维立体可视化模拟手术系统的建立，为正颌外科截骨矫治牙颌面畸形术前手术方案制定提供实用有效的技术手段和全心的科学方法，改变仅凭主观经验诊断畸形和设计手术方案的传统模式，可在计算机屏幕前制定手术方案进行医患交流，共同协商，提高了正颌外科手术安全性、精确性和矫治效果。     

颅颌面三维可视化模型的构建及应用

目的:构建基于CT影像数据的颅颌面硬软组织三维可视化模型,为进一步的三维分析诊断、手术模拟和预测构建基础平台.方法:系统获取患者CT颅颌面扫描的原始数据,经过二维预处理,三维预处理,运用改进的移动立方体算法,即移动四面体法完成基于断层图像的三维表面重建;运用基于小波的脚印法实现体重建,最终获得颅颌面三维可视化模型.结果:颅颌面三维可视化模型能够清晰地显示颅颌面复杂结构完整的形态,清楚的表面.临床医生能够对重建的三维模型动态旋转,从任意视角观察颅颌面软硬组织的畸形特征,也能通过任意切割显示颅颌面内部解剖结构.同时它具备良好的用户界面,临床医生使用方便.结论:解决了金属托槽X线反射、患者X线照射剂量及重建时间效率等问题,达到了预先设计目标,能够在临床得以实际应用.     

乳腺癌运动干预研究进展的可视化分析

目的 分析“乳腺癌运动干预”领域的研究热点及趋势,以期为乳腺癌运动干预方案设置提供理论依据。方法 以Web of Science核心数据库近五年所收录的乳腺癌运动干预类的7 134篇文献为对象,运用CiteSpaceⅤ进行可视化知识图谱分析,生成可视化图谱包括学科分布、国家或地区分布、关键词共现或突显、关键词时间线图谱等进行分析。结果 近年“乳腺癌运动干预”领域得到了快速的发展,学科分布主要集中在心血管系统与心脏病学和肿瘤学等。美国、英格兰和意大利等国家发文量排名靠前。身体质量指数、生活质量中介中心性分别为0.81、0.52,在知识图谱中有着重要的地位。关键突显图谱和时间线图谱显示心脏毒性是该领域的研究热点。结论 乳腺癌运动干预研究热点主要集中在心血管及其相关领域,目前处于高速发展阶段。未来研究方向包括体重控制、生活质量和心脏毒性。     

形象化健康教育模式对肠造口患者短期生活质量的影响

目的探讨形象化健康教育模式对肠造口患者自我护理能力及短期生活质量的干预作用。方法采用随机对照方法对我科2008年7月~2009年2月收治的53例直肠癌结肠造口患者随机分为观察组(27例)和对照组(26例)。观察组患者采用形象化健康教育模式,对照组患者采用传统护理方法。使用欧洲癌症研究与治疗组织的生活质量核心量表(EORTC QLQ-C30)V3.0中文版分别对两组病人入院时、出院后3个月的生活质量进行评分。结果观察组患者躯体功能、角色功能、情绪功能、认知功能、社会功能和总体健康状况方面在出院后3个月时均优于对照组,P0.05,差异有显著意义。结论形象化健康教育模式较传统护理方法能快速提高肠造口患者自我护理能力,并能显著改善肠造口患者的短期生活质量。