摘要
随着社会的发展和科技水平的进步,计算机技术也在不断提高,医学影像在对疾病的诊断和研究中也越来越重要。自从1895年伦琴(Wilhelm Rontgen)发现X光后,人们在此道路上不断前行创新,已经取得了不小的进步,本文就是在前人的研究基础上,对X射线相干散射在医学中的应用设计了实验并进行总结。
疾病都需要好的诊断才能治愈,但是有很多疾病不能靠人类的肉眼发现,如血液鉴定技术。从最原始的望闻问切到现代医学的发展,仍然有很多疾病是无法查明原因的,比如早期的骨折、肿瘤等。直到X射线出现,医生可以不开刀来查看病人的内脏、骨骼等病变。但是这些都离不开计算机的配合,随着软件系统的不断更新,现如今大部分医院都应用HIS,RIS,PACS等软件作为医学影像数字图象处理软件,从现代医学的角度来说,医生通过仪器拍出的X光片,通过传输媒介到计算机,在通过PACS软件进行处理,使其变得更加清晰可见,这样医生既可以通过web打开图像,也可以通过X光片进行诊疗,这样做,大大提高了诊疗的准确性和医疗水平,同时也大大缩短了诊疗的时间。
X射线可以完成多项任务,比如探测土质底层,爆炸性物品,医学成像等,在现代医学领域,X射线相干散射是一个重要研究方向,研究中对临床影像设备条件下X射线相干散射进行成像,通过改进医学影像设备的准直、聚焦,使所得到的图像更加清晰可见。再经过后期用数字图象处理软件对图像进行处理,从而获得光子能量空间分布的图像和曲线,进一步深化了实验研究结果。通过对医学影像设备的改造,获得了更具有说服力的实验图像,经过对实验图像的算法分析,面向医学领域的X射线相干散射成像将是进一步的研究目标。通过对普通X光射线仪器上进行的X射线相干散射成像研究,是此研究方向发展的重要部分,通过对实验设备的不断优化和改进,从而达到预期的效果。
本文在研究了中外对X射线相关技术的基础上,分析了X射线相干散射的成像原理,包括DEI技术和CSCT技术。并应用了这些技术设计了X射线相干散射的实验,试验中针对图像拼接和图像增强算法,对医学映像仪器和电脑的实验配置分别进行了改进,并详细描述了实验过程,通过对十五个备检品进行算法实验后,可以得到如下的基本结论:1、形心算法所计算出的形心与理想中的圆心会有不同程度的偏离;2、当估计圆心偏离理想圆心的时候相关强度会随之而降低;3、理想中的圆心具有其他圆心所没有的全局域中最小标准偏差和最大相关强度。综上所述我们可以知道,相关算法有效且收敛。
Thanks to the development and the enhancement of the society, and the incessantimprovement of science and technology, beneficially and constantly improves the MedicalImaging Work. People are making innovations in the field since X-Ray was discovered byWilhelm Rontgen in1895. The correct and necessary methods of treatment are in need tofight against diseases. There are plenty of diseases existing out of the human’s sight.Methods of treatment include the Traditional Chinese Medical Science and Identification ofBlood, can rarely ascertain a great many agnogenic diseases, such as the bone fracture andthe tumor in the early time. By the appearance of the X-Ray, it is unnecessary for doctors bymedical operation to check the pathological changes of patients’ viscera and bones. However,all the things can not be realized without computers. Nowadays, with the constantly updateof the software system, softwares such as HIS, RIS, PACS are widely used in most hospitalsas the medical imaging digital image processing softwares. From the perspective of modernmedicine, the X-Ray images made by apparatus, transmitted into computers by transmissionmedia, manipulated by PACS software, can be more visible and readable. Therefore, doctorscan diagnose and treat by the opened images on web and by X-Ray. So the accuracy and themedical treatment level of therapy is immensely advanced, meanwhile the during-time oftherapy is shortened a great much.
X-Ray can assist to multi-task, such as soil ground floor detection, explosive goods andmedical imaging. Diversiform radials generate from X-Ray, such as the scattering, therefraction and the diffraction of X-Ray. In the field of modern medicine, the coherentscattering of X-Ray develops an important research area. On the research of X-Ray coherentscattering imaging in the condition that clinical imaging equipments involve, the relatedimages can be a lot more visible and readable by enhancing the collimation and the focus ofmedical imaging equipments. What’s more, the images and curves of the photon energyspace distribution can be achieved through the process of the digital image processingsoftware. So the research results are further intensified. People are able to obtain the moreevidential experimental images through advancing the medical imaging equipments andthrough the algorithm analysis of the experimental images. The X-Ray coherent scatteringimaging in the field of medical science, will be the further research target in the future. It isan important step of the development of this research area. Through the unceasingoptimization and enhancement of the experimental equipment, the expected effect can be achiedved.
This paper analyses the imaging principles of the X-ray coherent scattering, based onresearching Chinese and foreign technologies. The X-ray coherent scattering includes bothDEI and CSCT. Applying the technical of X-ray coherent scattering, I designed of anexperiments which improve medical images and computer experiments. Analyzing fifteenexperiments by centroid algorithm, we could obtain the following basic conclusions:1, thecentroid algorithm to calculate the centroid and the ideal of the center have varying degreesof deviation;2, when the estimated deviation from the ideal center when the center willfollow reduce the related strength;3, ideal in the center circle with the other domains that arenot global minimum standard deviation and maximum correlation strength. In summary,relevant algorithm is effective and r convergence.
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