MRI海马特殊扫描在颞叶癫痫海马硬化诊断中的应用

目的：确定癫痫病因和定位癫痫病灶对制定手术方案及判断预后至关重要。近年来研究证实70％－90％的慢性癫痫的病人都存在一定程度的结构异常。高清晰度MRI的出现对顽固性癫痫诊断具有划时代的意义。本研究就MRI在评估颞叶癫痫海马硬化中的作用作初步探讨。方法：对顽固性颞叶癫痫26例应用MRI对病人进行海马特殊扫描。结果：在26例顽固性颞叶癫痫病人行海马特殊MRI扫描中，海马和杏仁核区低恶度脑胶质瘤2例，脑囊肿1例，小AVM1例，脑脓肿1例。海马硬化19例（10右侧，7例左侧，2例双侧）。2例未见异常，MRI所示结构异常率为92％（24／26），海马硬化率为73％。前颞叶萎缩18例，侧脑室颞角的不对称性22例，T2加全像高信号表现11例。颞叶癫痫海马硬化MRI主要表现为：1、前颞叶萎缩；2、侧脑室颞角的海马硬化MRI主酹现为：1、前颞叶萎缩；2、侧脑室颞角的不对称性；3、海马萎缩；4、T2加全像高信号表现；5、海马内结构的丢失。结论：应用MRI海马特殊扫描技术诊断颞叶癫痫海马病变其准确率为92％，其对诊断颞叶癫痫海马病变具有较高的实用价值。     

MRI海马特殊扫描在颞叶癫痫海马硬化诊断中的应用

随着影像学发展和显微外科技术的进步,使颞叶癫痫外科治疗取得了长足的进展。尽管外科方法治疗颞叶癫痫是一种行之有效的方法,但确定癫痫病因和癫痫病灶定位对制定手术方案及判断预后至关重要[1,2]。近年来研究证实70%～90%的癫痫的病人都存在一定程度的结构异常。高清晰度MRI的出现对顽固性癫痫诊断具有划时代的意义。本文初步探讨了MRI在评估颞叶癫痫海马硬化中的作用。1材料与方法经临床表现和头皮EEG及视频EEG诊断为顽固性颞叶癫痫26例。所有病人均经神经内科医师检查、神经心理学检测及长时视频EEG监测。男15例,女11例,年龄6～56…     

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。     

MRI立体定向尾状核个体化数字化图谱的研究

目的探讨依据MRI立体定向尾状核资料建立个体化数字化图谱的可行性。方法对1例成年男性健康自愿者在标准的脑立体定向空间做1mm层厚，间距0mm的MR轴位和冠状位脑扫描，对经MRI扫描后转存的尾状核图像进行识别、分割、提取、匹配与三维重建。结果三维重建的尾状核表面光滑、形态逼真，清晰地显示了个体尾状核在标准立体定向空间中的位置，可直观显示，并能从任意角度浏览尾状核的形态。结论基于MRI资料的个体人脑结构数字化、可视化的三维重建具有可行性．但需解决计算机自动化识别、自动配准和分割问题。     

三叉神经痛伽玛刀治疗前MRI定位扫描序列研究

伽玛刀是治疗三叉神经痛的方法之一。 MRI是其定位的主要工具 ,常规采用 SE序列 [1]。但是在工作中 ,我们发现部分人群中三叉神经根显示欠佳。为此我们设计了一种新的扫描序列 ,并与常规 SE序列比较 ,现报道如下 :材料及方法正常对照组 2 0例 ,无三叉神经痛病史。以 3D-TOF- SPGR序列 MRI扫描 ,脑内无异常 ,男 7例 ,女 1 3例 ,年龄 35～ 72岁 ,平均 55岁。三叉神经痛病人组 2 1例 ,男 1 5例 ,女 6例 ,年龄 33～ 77岁 ,平均63岁 ,均有典型三叉神经痛的病史 ,临床确诊为三叉神经痛。 8例使用 SE序列 ,8例用三维时间飞越破坏性稳态回聚…     

中国人脑MRI立体定向活体尾状核数字化的三维重建

依据1例38岁成年男性健康志愿者的MRI立体定向尾状核资料建立个体化数字化图谱。在以AC-PC线为基准线的标准脑立体定向空间对志愿者做1 mm层厚,间距0 mm的MR轴位和冠状的脑扫描,利用哈尔滨工业大学生物研究中心研究开发的软件系统对经MRI扫描后转存的尾状核图像进行三维重建,软件提取分割的尾状核轮廓后执行重建命令。三维重建的尾状核表面光滑、形态逼真,首次清晰地显示了健康国人活体尾状核在大脑标准立体定向空间中的位置,可直观显示,并能从任意角度浏览尾状核的形态。提示基于MRI资料的个体人脑结构数字化、可视化的三维重建具有可行性。     

老年轻度认知障碍患者海马萎缩的MRI定量测定

目的:探讨老年人轻度认知障碍(MCI)患者海马体积的变化及其与简易智力状态检查(MMSE)的相关性。方法:对15例MCI和16例健康老年人(对照组)行核磁共振(MRI)及MMSE检查,经标准化处理和年龄性别修正后比较海马体积变化及其与MMSE评分的相关性。结果:MCI组(6079±187mm~3)、较对照组(7062±204mm~3)的海马体积显著减少(P<0.01),萎缩程度14％。海马体积与MMSE评分相关性检测MCI组(r=0.33)、对照组(r=0.25),相关性均不明显(P>0.05);两组人群合并后,全体研究对象的海马体积与MMSE评分呈显著正相关(r=0.069,P<0.001)。结论:海马萎缩的MRI定量测定有助于MCI的诊断;海马体积萎缩是老年人认知功能下降的关联因素。     

数字化构建人脑豆状核及其亚结构图谱

目的 应用<中国数字化可视人体图谱>男性尸脑切片构建豆状核及其亚结构的三维可视化图谱.方法 利用哈尔滨工业大学Bio-X中心开发的软件对尸脑切片豆状核及其亚结构进行识别、分割等图像转换与处理,并进行三维重建.结果 三维重建后的结果显示豆状核为一个前后径较长、上下径较高、左右径相对较窄,近似蚕豆形状的灰质团块.应用透明处理方法进行的三维重建清晰地显示了豆状核及其亚结构的空间位置关系.结论 利用超薄尸脑切片可以成功构建人脑核团的亚结构.

Abstract：

Objective To establish a 3D atlas of the lenticular nuclei and its subnucleus with the cryosection images of the male from Atlas of Chinese Visible Human.Method The lenticular nuclei and its subnucleus were segmented from the cryosection images and reconstructed with the software developed by Harbin Institute of Technology.Results 3D model of the lenticular uuclei illustrated that it was fabaceous with its anteroposterior and superoinferior diameter longer,and the mediolateral diameter shorter.The spatial relationship between the lenticular nuclei and its subnucleus was clear with the surface of the lenticular nuclei semitransparent.Conclusions It is feasible to establish 3D model of the subnucleus in the human brain with the cryosection images.     

第三脑室MRI立体定向解剖学研究

目的完善中国人脑立体定向MRI脑图谱,为立体定向手术及脑室内窥镜手术等有关三脑室区手术提供解剖学基础。方法采集健康中国人脑MRI数据100例,在标准立体定向空间内测量三脑室体积。选取可测量三脑室长度及高度的MRI图像各50例,分别对三脑室的长度及高度进行测量。选取三脑室显示清晰的MRI图像1例,对三脑室进行三维重建。结果活体健康中国人脑MRI上三脑室的平均长度为21.15±1.56 mm;平均高度为19.21±1.94 mm;平均体积1424.68±196.47 mm3。结论不同性别之间三脑室的长度与高度无显著差异(P>0.05);随年龄的增长,三脑室的体积逐渐增加;同一年龄段不同性别间三脑室体积存在显著差异,男性大于女性(P<0.05),三维重建三脑室可行。     

低位脑神经MRI与薄层断面及三维重建对照研究

低位脑神经包含舌咽神经、迷走神经、副神经和舌下神经。舌咽神经、迷走神经和副神经经延髓后外侧发出入颈静脉孔，此三对脑神经由一系列根丝附着于延髓的橄榄后沟，纤维细小，彼此不易区分，形成舌咽-迷走-副神经复合体。舌下神经由延髓腹侧沟发出入舌下神经管。低位脑神经与脑干及颅底关系密切，是神经外科手术较难处理的区域和解剖结构，也是目前影像学诊断的难点之一。由于低位脑神经位置深在，解剖学关系复杂，相对限制了脑干和颅底外科手术的发展。     

翼腭窝三维可视模型的建立及内镜下解剖结构分析*☆

背景：正确理解翼腭窝解剖是翼腭窝手术的关键,翼腭窝可视模型对帮助医生详细了解内镜下翼腭窝的复杂结构非常重要。 目的：建立翼腭窝三维可视模型显示内镜下翼腭窝的相关解剖结构,为翼腭窝手术入路提供指导。 方法：依据一位患者冠状位CT血管成像数据,通过MOI自由设计大师和SketchUp软件构建三维数字模型,进行手术计划,模拟经鼻内镜入路,开放上颌窦口,去除上颌窦后壁,进入翼腭窝,提供特定视野及空间方向观察。 结果与结论：成功构建翼腭窝及相邻解剖结构的可视模型,为鼻内镜手术入路提供帮助,使用者可与模型进行交互作用并可任意操作模型(包括射线模式,内部观察),可在特定视野内随时观察,为手术计划提供准确的形态信息,包括颌内动脉及其分支,腭降动脉,蝶腭动脉,后鼻动脉,圆孔,翼管,蝶窦,眶下裂,视神经管,翼突,颈内动脉等。可见内镜下空间方向发生改变。结果提示,SketchUp和MOI 构建翼腭窝模型方法简单可行, 可帮助理解内镜下翼腭窝的解剖结构,可模拟手术过程。     

Cytoarchitectonically‐driven MRI atlas of nonhuman primate hippocampus: Preservation of subfield volumes in aging

Identification of primate hippocampal subfields in vivo using structural MRI imaging relies on variable anatomical guidelines, signal intensity differences, and heuristics to differentiate between regions (Yushkevich et al., 2015a). Thus, a clear anatomically‐driven basis for subfield demarcation is lacking. Recent work, however, has begun to develop methods to use ex vivo histology or ex vivo MRI (Adler et al., 2014; Iglesias et al., 2015) that have the potential to inform subfield demarcations of in vivo images. For optimal results, however, ex vivo and in vivo images should ideally be matched within the same healthy brains, with the goal to develop a neuroanatomically‐driven basis for in vivo structural MRI images. Here, we address this issue in young and aging rhesus macaques (young n = 5 and old n = 5) using ex vivo Nissl‐stained sections in which we identified the dentate gyrus, CA3, CA2, CA1, subiculum, presubiculum, and parasubiculum guided by morphological cell properties (30 μm thick sections spaced at 240 μm intervals and imaged at 161 nm/pixel). The histologically identified boundaries were merged with in vivo structural MRIs (0.625 × 0.625 × 1 mm) from the same subjects via iterative rigid and diffeomorphic registration resulting in probabilistic atlases of young and old rhesus macaques. Our results indicate stability in hippocampal subfield volumes over an age range of 13 to 32 years, consistent with previous results showing preserved whole hippocampal volume in aged macaques (Shamy et al., 2006). Together, our methods provide a novel approach for identifying hippocampal subfields in non‐human primates and a potential ‘ground truth’ for more accurate identification of hippocampal subfield boundaries on in vivo MRIs. This could, in turn, have applications in humans where accurately identifying hippocampal subfields in vivo is a critical research goal.     

MRI影像下股骨髁间窝三维数字化解剖学数据与实体解剖测量值的差异

背景：X射线、CT、MRI二维图像测量股骨髁间窝受投照体位、选取测量层面等影响,测量准确性较差。 目的：比较MRI影像下股骨髁间窝三维数字化模型测量值和尸体实体解剖测量值的差异,探讨基于MRI影像下三维数字化模型的准确性。 方法：对尸体膝关节标本行MRI扫描,将MRI图像导入Mimics软件对股骨髁间窝进行三维数字化重建,测量三维数字化髁间窝的相关解剖学数据,同时对尸体标本进行解剖,测量实体解剖学数据。 结果与结论：三维数字化重建髁间窝顶长度、髁间窝宽度、内外髁宽度、髁间窝指数测量值与实体解剖测量值差异无显著性意义(P > 0.05)。说明基于MRI影像下股骨髁间窝的三维数字化模型能够准确反映实体标本信息,可用于正常人股骨髁间窝的解剖学研究。     

标准立体定向空间构建人脑苍白球内侧部数字化解剖图谱

目的 在标准立体定向空间应用《中国数字化可视化人体图谱》男性尸脑切片构建豆状核亚结构—苍白球内侧部(Gpi)数字化图谱. 方法 对数字化可视化人体图谱尸脑切片解剖学图像进行Gpi及前连合、后连合的识别与分割等处理,并应用软件对处理后的Gpi进行三维重建,并建立立体定向坐标系. 结果 三维重建的Gpi为近似蚕豆状的灰质团块,同时构建了壳核及苍白球外侧部(Gpe),图谱能够清晰的显示三者在立体定向空间的位置关系.三维可视化的效果为豆状核可以在立体定向空间任意角度的旋转、缩放. 结论 利用超薄尸脑解剖图像可以在标准立体定向空间成功对颅内神经结构亚核团进行三维重建.     

Three-dimensional visualization and quantification of the benzodiazepine receptor population within a living human brain using PET and MRI

Positron emission tomography (PET) in combination with receptor-selective high-affinity radioligands allows the characterization of neuroreceptor distributions in the living human brain. Thus far, the visualization and quantification of receptors with PET have been limited to series of two-dimensional (2D) image planes of the anatomic receptor distribution. The development of high-resolution PET has increased the number of planes to approximately 50, supplying an excessive amount of image information from a single experiment. The inherent limitations of 2D techniques make them insufficient to apprehend and efficiently analyze this cumbersome amount of data. In the present communication we describe procedures to visualize and quantify in three dimensions (3D) the total image information from the compound set of 47 2D planes of a PET experiment using commercially available software. Three-dimensional computer graphic and volume rendering techniques were used to analyze and display the results. For the experimental application the benzodiazepine (BZ) antagonist [^t1C]flumazenil was used as radioligand to visualize the BZ receptor (BZR) population in the brain of a healthy human subject. Three-dimensional images of the radioligand binding receptor population were displayed with regard to volume and form in relation to the corresponding anatomic structures in the brain reconstructed from MR images. The volume-rendering technique allowed the inspection of PET signals representing BZR populations in the interior of the hemisphere as viewed from the medial projection. Thresholding and seeding techniques were used to define volumes and quantities. Using the PET data and volume rendering, the total amount of cerebral BZRs (N_Cerebrum) and the apparent volume they take into account (V^app _BZR, Cerebrum) could be calculated for the first time using an automated procedure. The cerebrum of the healthy subject contained 17.6 nmol of BZRs in a voulume of approximately 1.25 L. The principles and application of the technical development described offer new dimensions to clinical neuroscience and should be practically useful for automated quantitative determination of neuroreceptor number in brain regions of patients with neuropsychiatric disorders and in relation to drug treatment.     

Benign and secondary progressive multiple sclerosis: a preliminary quantitative MRI study

In a preliminary study, we compared by means of quantitative magnetic resonance imaging (MRI) methods (1) the T2 values and the decay characteristics of chronic brain lesions, (2) the T2 values of normal-appearing frontal white matter (NAWM) and (3) brain lesion volumes in patients with benign and secondary progressive multiple sclerosis (MS) in order to evaluate the mechanisms underlying the development of disability. Eleven clinically definite MS patients with either benign MS (n = 5) or secondary progressive MS (n = 6) were studied. Fifty-two chronic lesions (identified by comparison with MRI scans obtained at least 12 months previously) were identified. The mean T2 of large lesions (cross-sectional area greater than 41 mm²) and of the NAWM was similar in both clinical groups. However, small lesions had higher mean T2 values (P < 0.01) in the benign group, probably at least in part because of partial volume effects. Analysis of large lesions revealed biexponential T2 relaxation in 6 of 8 secondary progressive and in 2 of 16 benign lesions, perhaps indicating a greater degree of axonal loss in large lesions of patients with secondary progressive MS. Patients with secondary progressive MS had higher (although not significant) total and infratentorial lesion loads than those of the benign group. These preliminary findings suggest, but do not establish, that variations in the extent, site and pathological nature of lesions may all contribute to different patterns of disease evolution in MS.     

可视化上颌骨与牙列三维模型的建立

基于美国可视人计划切片图像数据集建立三维模型。图像分割主要在Adobe Photoshop环境下半自动实现，三维模型的构建和修正采用Mercury公司的Amira软件实现骨模型。建立了上颌骨、上牙列精细的三维模型，此模型可精确的显示眶下孔、眶下沟、神经管；且每颗牙齿独立建模，并能严密地与上颌骨的牙槽配合。结果提示重建后的上颌骨与牙列模型三维效果逼真，立体感强，准确地显示了上颌骨、牙列及精细结构，为教学、科研及虚拟手术等提供了准确逼真的模型。