脑部肿瘤放疗诱发癫痫的临床护理对策

目的探讨脑部肿瘤放疗诱发癫痫症的临床护理措施。方法以脑部肿瘤切除术结合放疗治疗的患者180例为研究对象,随机分为实验组和对照组各90例,对照组采用常规护理,实验组在常规护理的基础上采用综合护理措施,包括心理护理、头部固定护理,针对癫痫发作的预防和对抗护理、用药指导及饮食护理等措施,比较2组护理后癫痫的发患者数及发病率。结果对照组癫痫中重度发作46例,轻度发作25例,未发作19例;实验组癫痫中重度发作11例,轻度发作15例,未发作64例,组间比较差异具有统计学意义(P0.05)。结论综合护理措施可有效降低脑部肿瘤放疗诱发癫痫症的发生,提高临床疗效及患者生存质量。     

脑室肿瘤的MRI诊断

目的探讨脑室肿瘤的MRI表现及其诊断价值。方法回顾性分析40例经手术及病理证实的脑室肿瘤患者。所有患者均行T1WI、T2WI增强扫描,10例患者行FLAIR扫描,并对其病变部位、大小、边界、信号强度、增强特点进行分析。结果40例患者中,31例为原发于脑室内的肿瘤,其中,侧脑室14例、第三脑室4例、第四脑室13例。另外,小脑蚓部4例、松果体区3例、丘脑1例、鞍区1例。MR图像表现各异,大体可分为脑室团块与脑室囊肿。结论扩散加权成像(DWI)及FLAIR序列扫描对脑室肿瘤的定性有很大价值,脑室肿瘤的MR诊断必须将影像学表现与肿瘤部位、患者年龄结合起来方能作出较为准确的诊断。     

MRI图像的小波融合处理

背景：小波图像融合是将两幅图像融合在一起,以获取对同一场景的更为精确、全面、可靠的图像描述。目的：用小波变换图像融合技术融合MRI脑梗死图像,以恢复缺损图像。方法：图像融合的主要机制是利用二维小波分析法对MRI脑梗死图像进行小波分解,并对高低频信号采用多种融合方式进行融合。通过对比不同融合方式后的效果图,找出最适合本部位MRI图像的融合方法。结果与结论：不同方式的融合技术能成功修复不同的缺损部位,多种融合方式的合适组合能完全修复多处缺失部位。对于文中给出的MRI脑梗死图像,采用最小值融合方式的融合效果最好。提示使用二维小波分析法处理医学图像,简便快捷,能有效改善图像的视觉效果,辅助临床诊断。     

肿瘤样多发性硬化的临床与MRI的对照分析

我们总结了6例以肿瘤样为表现的多发性硬化(Multiple sclerosis，MS)．现报告如下。     

点对称距离模糊C均值聚类算法在脑部MRI图像分割中的应用

背景：在传统的图像分割方法中,模糊C均值聚类算法应用十分广泛。 目的：将改进的模糊C均值聚类算法应用到MRI图像的分割中,提高MRI图像分割的准确度。 方法：针对传统的基于Minkowski距离的模糊C均值聚类算法,提出了基于点对称距离的模糊C均值聚类算法,并将其运用到了脑部MRI图像分割中。 结果与结论：实验结果表明,与模糊C均值聚类算法相比,点对称距离的模糊C均值聚类算法有明显的优势。     

枕骨大孔区肿瘤的MRI诊断及显微外科治疗

目的探讨枕骨大孔区肿瘤的MRI诊断、类别和显微外科治疗方法。方法回顾分析MRI诊断和显微手术治疗51例枕骨大孔区肿瘤,根据肿瘤的MRI及类别选择手术入路,经枕下后正中入路手术切除41例,经枕下远外侧入路手术切除10例。结果肿瘤全切除37例(72.5%),次全切除13例,部分切除l例。临床症状改善者40例,保持原有症状者5例,症状较术前加重4例,术后死亡2例。术后随访到45例,随访期内复发3例。结论枕骨大孔区肿瘤种类及表现差异性大,MRI检查可提供准确的定位和诊断;根据MRI成像特点选择恰当的手术入路和采用显微外科手术切除肿瘤可获得良好的临床效果。     

基于调幅-调频与熵图多模态医学图像的配准

背景：基于传统互信息量的多模态医学图像配准方法配准时需要利用二维直方图或者Parzen窗函数的方法估计概率密度分布,进而计算互信息量,这种方式计算速度慢,而且只考虑了图像的灰度信息,容易出现误配。 目的：针对目前主流的配准方法鲁棒性差、耗时的缺点,提出了一种新的基于调幅-调频(AM-FM)特征互信息量的快速配准方法。 方法：该方法考虑了图像的空间和结构信息;首先通过AM-FM模型对图像进行分解,得到图像的AM-FM特征,与图像的灰度特征一起组成高维特征;然后利用熵图和最小生成树加快AM-FM特征互信息量的计算,从而实现了医学图像的快速配准。 结果与结论：对20组磁共振T1-T2加权图像、CT/正电子发射计算机断层成像图像进行了实验,结果表明该方法在图像空间分辨率较低,有噪声影响等情况下均可以达到较好的结果,且配准精度优于国际上的主流方法,具有计算速度快,精度高,鲁棒性强的特点,适于临床应用。     

一种人眼调节时MRI图像的数字化处理方法

针对目前关于人眼调节机制理论的争论,为更加准确地研究人眼调节时MRI图像的形态变化特点,应用一种新的数字化图像处理方法提高图像识别效果。利用高分辨的MRI采集同一受试者在调节时的人眼图像,通过最大互信息方法对图像对位频闪,实现图像的匹配定位,便于眼科医师对人眼组织的变化进行定性观察与分析。用最大互信息的配准方法编制的软件处理后的图像可以更加直观准确地便于眼科医师的识别判断,在此基础上可以方便地获得定性变化的信息。结果提示最大互信息的配准方法应用于人眼调节时的MRI图像可以提高临床医师对于图像变化的识别质量,并为图像变化的定性和定量研究提供更好的基础。     

术中MRI的应用现状与展望

核磁共振成像（Ｍａｇｎｅｔｉｃ　Ｒｅｓｏｎａｎｃｅ　Ｉｍａｇｉｎｇ，ＭＲＩ）具有良好的分辨率、任意平面和基本实时的成像能力，应用于神经外科手术中可清楚显示脑组织移位，手术器械位置，病灶切除情况及残留部分的实际位置，有无继发出血或水肿，以引导手术器械准确到达深部病灶。明显增加手术的有效性和安全性，改善预后。     

椎管内肿瘤患者行图像引导放疗的护理

原发性椎管内肿瘤是指原发于脊椎、脊髓内和椎管内各种组织的肿瘤,不包括转移瘤、椎旁组织及脊椎的肿瘤[1]。此类疾病首选手术治疗,但部分肿瘤仍难于全部切除,需行术后放疗[2]。患者的放疗不准确,将导致肿瘤剂量不足或危及器官剂量过高[3]。图像引导放射治疗(image guide radia-tion therapy,IGRT)是目前精确放疗技术的主要组成之一,图像引导放疗系统将成像系统与加速器相结合,通过采集每次治疗前和治疗中的图像即CT图像,来确定治疗靶区是否     

Structural covariance in schizophrenia and first-episode psychosis: An approach based on graph analysis

Schizophrenia is a neurodevelopmental disorder that produces abnormalities across different brain regions. Measuring structural covariance with MRI is a well-established approach to investigate common changes in distinct systems. We investigated structural covariance in schizophrenia in a large Brazilian sample of individuals with chronic schizophrenia (n = 143), First Episode Psychosis (n = 32), and matched healthy controls (n = 82) using a combination of graph analysis and computational neuroanatomy.Firstly, we proposed the connectivity-closeness and integrity-closeness centrality measures and them compared healthy controls with chronic schizophrenia regarding these metrics. We then conducted a second analysis on the mapped regions comparing the pairwise difference between the three groups.Our results show that compared with controls, both patient groups (in pairwise comparisons) had a reduced integrity-closeness in pars orbitalis and insula, suggesting that the relationship between these areas and other brain regions is increased in schizophrenia. No differences were found between the First Episode Psychosis and Schizophrenia groups. Since in schizophrenia the brain is affected as a whole, this may mirror that these regions may be related to the generalized structural alteration seen in schizophrenia.     

The influence of carmustine wafer implantation on tumor bed cysts and peritumoral brain edema

The development of perifocal edema and tumor bed cyst has been reported after implantation of biodegradable carmustine wafers for the treatment of malignant gliomas. We retrospectively evaluated these changes in a series of patients; 19 consecutive patients with malignant glioma who received carmustine wafer implantation at our hospital from January 2013 through July 2013, and 28 patients who underwent surgery prior to our institution’s initiation of carmustine wafer implantation, as historical controls. The volume of the tumor bed cyst and perifocal edema was calculated on MRI acquired at four time points: ⩽72 hours after surgery for baseline, and at 1–4, 5–8, and 9–12 weeks after surgery. The volume of the tumor bed cyst in the wafer group increased significantly relative to the control group at all time points (p = 0.04). Opening of the ventricle was inversely correlated with enlargement of the tumor bed cyst in the wafer group (p = 0.04). The change in the volume of perifocal edema in the wafer group was not significantly different (p = 0.48), but exhibited a considerable increase in patients with anaplastic oligodendroglioma relative to glioblastoma patients in the wafer group (p = 0.01). We demonstrated significant enlargement of the tumor bed cyst volume after carmustine wafer implantation, as well as the development of marked perifocal edema in patients with anaplastic oligodendroglioma.     

Acute cerebellar stroke and middle cerebral artery stroke exert distinctive modifications on functional cortical connectivity: A comparative study via EEG graph theory

ObjectiveWe tested whether acute cerebellar stroke may determine changes in brain network architecture as defined by cortical sources of EEG rhythms.MethodsGraph parameters of 41 consecutive stroke patients (<5 days from the event) were studied using eLORETA EEG sources. Network rearrangements of stroke patients were investigated in delta, alpha 2, beta 2 and gamma bands in comparison with healthy subjects.ResultsThe delta network remodeling was similar in cerebellar and middle cerebral artery strokes, with a reduction of small-worldness. Beta 2 and gamma small-worldness, in the right hemisphere of patients with cerebellar stroke, increase respect to healthy subjects, while alpha 2 small-worldness increases only among patients with a middle cerebral artery stroke.ConclusionsThe network remodeling characteristics are independent on the size of the ischemic lesion. In the early post-acute stages cerebellar stroke differs from the middle cerebral artery one because it does not cause alpha 2 network remodeling while it determines a high frequency network reorganization in beta 2 and gamma bands with an increase of small-worldness characteristics.SignificanceThese findings demonstrate changes in the balance of local segregation and global integration induced by cerebellar acute stroke in high EEG frequency bands. They need to be integrated with appropriate follow-up to explore whether further network changes are attained during post-stroke outcome stabilization.     

阿尔茨海默病患者的脑单光子体层摄影术及磁共振显像的研究

），和第四脑室（F＝4．10）体积高于对照组，差异有显著或非常显著性（P＜0．05－0．01）。（5）AD组各级年龄组间的MRI指标差异均无显著性。（6）AD组与对照组的同年龄组MRI比较，AD组存在灰质体积缩小，总脑脊液，脑室外脑脊液和第三脑室体积增加，右侧海马体积萎缩。（7）AD组的聚类分析结果，以左顶叶，右顶叶的SPECT计数值为变量，AD可被聚为I，Ⅱ，Ⅲ三类，简明智力状态检查评分分别为20－26，13－19，5－11，（8）左海马体积，右海马体积与扣带回，双侧顶叶，丘脑，枕叶及右侧基底节放射性计数比值存在高度相关性。结论：AD患者功能性和结构性改变较增龄性改变范围广，幅度大，其双侧海马体积与顶叶及部分边缘系统灌注相关，提示上述结构共同参与AD的病理机制，双侧顶叶灌注能对AD做有效的疾病程度分类。     

基于Matlab距骨快速图像分割与动画生成的算法

背景：骨科手术导航是利用计算机和机器视觉技术,使医师在计算机屏幕的指导下完成接骨手术。为了后续定位工作的开展,首先必须基于CT图像序列在计算机上对下肢骨进行图像分割、三维重建和动画显示,并对其位姿进行测量。 目的：在计算机上快速自动地实现距骨图像的分割、三维可视化及动画显示,为建立新型的足部手术导航系统搭建计算机显示平台。 方法：基于足部CT图像序列,提出下列算法并采用Matlab编程实现：①基于最大熵原则对足部图像进行阈值分割以提取其中所有足部骨骼。②将形态学算法与Live-wire算法相结合快速自动地从该足部骨骼图像中分割出距骨。③利用移动立方体法对距骨表面进行三维重建。④采用图形学函数生成与显示距骨旋转的动画场景。 结果与结论：实验结果表明,上述算法准确度高且以较少的时间在普通 PC机上实现了距骨的三维可视化工作,可应用于足部手术导航的计算机显示平台中。     

基于非冗余平移不变小波变换的磁共振图像降噪**☆

背景：MRI成像机制决定了其时间/空间分辨率和信噪比之间存在矛盾,因此图像降噪变得十分必要。目前基于离散小波变换的降噪方法广泛应用,然而存在平移敏感性的缺陷。目前已出现了克服平移敏感性的离散小波变换,但其冗余性导致计算复杂度的快速增加。目的：针对图像降噪设计小波滤波器,减小降采样过程的影响,保持离散小波变换的非冗余性,并针对MRI图像Rician噪声的降噪进行分析。方法：由于平移敏感性主要是由于离散小波变换分解时降采样产生的混叠项带来的,在保证非冗余的前提下,提出了通过减小混叠项的影响来减小平移敏感性。在此基础上,设计了一个双正交小波。最后,将其以常见的阈值降噪方法应用到磁共振图像Rician噪声的降噪中。结果与结论：文章提出了设计小波滤波器的新方法,即满足严格重构条件外满足一些附加要求,最后将设计过程简化为一个有约束条件的最优化过程。将设计的双正交小波应用于MR图像,仿真结果表明降噪效果较通常小波有所改善,间接表明了设计思路和方法的有效性。     

MRI立体定向丘脑底核和杏仁核个体化、数字化、可视化图谱的研究

目的探讨建立个体化MRI立体定向丘脑底核（STN）和杏仁核（AM）数字化、可视化图谱的可行性。方法对1例成年男性健康自愿者应用1．5TMRI,在标准的脑立体定向空间做1mm层厚的MRI轴位脑扫描,在MRI上对STN和AM进行识别、手动分割、提取、存储和三维重建。结果三维重建的STN和AM表面光滑、形态逼真,清晰的显示了个体STN和AM在标准立体定向空间中的位置,可以直观的观察STN和AM的形态结构。重建后的STN和AM可以任意旋转、缩放及变换颜色。STN前后径较长,上下径和左右径相对较短,表现出典型的“双透镜”结构特点,而AM则表现出典型的“杏仁”形状。结论MRI立体定向个体化的STN和AM数字化、可视化具有可行性,如果要达到指导立体定向功能神经外科临床应用的目的,需解决计算机自动化识别、自动配准和分割问题。     

轮廓波及曲波和小波变换用于显微图像消噪的比较*****☆

背景：小波变换只能反映信号的零维奇异性,无法最优表示图像中的线奇异;而且小波变换只存在3个方向,这些都显著影响了它在图像处理领域的应用效果。针对小波变换的缺点,多尺度几何分析理论正在逐步发展,轮廓波变换和曲波变换就是其中的典型代表。目的：定性、定量地比较轮廓波、曲波和小波变换在图像消噪处理中的效果。方法：在简要介绍3种变换基本原理的基础上,比较它们在图像消噪领域的应用,以均方误差和峰值信噪比作为定量指标评价消噪效果,并将其应用于显微镜图像的消噪处理。结果与结论：综合定量评价指标和人眼视觉感受,曲波变换的消噪结果最佳,轮廓波变换效果次之,小波变换效果则不够理想。     

肿瘤坏死因子超家族成员4基因SNP rs3861950与脑梗死

目的 探讨肿瘤坏死因子超家族成员4(TNFSF4)基因SNP rs3861950与本地区脑梗死发病的关系.方法 采用TaqMan-PCR方法检测TNFSF4基因SNP rs3861950基因型与等位基因频率.湖南籍汉族脑梗死共287例,对照组为湖南籍汉族健康体检者共285名.结果 脑梗死组CC基因型(7.7%)分布与对照组(2.1%)相比,差异具有统计学意义(X2=9.553,P=0.008);C等位基因频率脑梗死组(0.190)高于对照组(0.137,X2=5.887,P=0.015).动脉血栓性脑梗死亚组与对照组比较其基因型(X2=9.396,P=0.009)及等位基因频率(X2=6.134,P=0.013)差异均有统计学意义.非条件Logistic多因素回归分析显示CC基因型使脑梗死发病的风险是其他危险因素的3.7倍(P=0.002,OR 3.706).结论 TNFSF4基因rs3861950 C→T与湖南籍汉族脑梗死发病相关,尤其与动脉血栓性脑梗死发病相关,rs3861950 C等位基因可能是湖南籍汉族脑梗死发病的独立危险因素.     

Brain signatures based on structural MRI: Classification for MCI,PMCI, and AD

Structural MRI (sMRI) provides valuable information for understanding neurodegenerative illnesses such as Alzheimer''s Disease (AD) since it detects the brain''s cerebral atrophy. The development of brain networks utilizing single imaging data—sMRI is an understudied area that has the potential to provide a network neuroscientific viewpoint on the brain. In this paper, we proposed a framework for constructing a brain network utilizing sMRI data, followed by the extraction of signature networks and important regions of interest (ROIs). To construct a brain network using sMRI, nodes are defined as regions described by the brain atlas, and edge weights are determined using a distance measure called the Sorensen distance between probability distributions of gray matter tissue probability maps. The brain signatures identified are based on the changes in the networks of disease and control subjects. To validate the proposed methodology, we first identified the brain signatures and critical ROIs associated with mild cognitive impairment (MCI), progressive MCI (PMCI), and Alzheimer''s disease (AD) with 60 reference subjects (15 each of control, MCI, PMCI, and AD). Then, 200 examination subjects (50 each of control, MCI, PMCI, and AD) were selected to evaluate the identified signature patterns. Results demonstrate that the proposed framework is capable of extracting brain signatures and has a number of potential applications in the disciplines of brain mapping, brain communication, and brain network‐based applications.