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。     

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。     

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.     

中国人MRI立体定向丘脑数字化图谱的研制

目的 探讨建立MRI立体定向数字化图谱的可行性,分析年龄对成人丘脑体积的影响.方法 选取健康中国成年自愿者行立体定向MRI扫描,在MRI上对丘脑进行识别、分割、提取、保存、匹配与三维重建,测量重建后丘脑的体积.结果 三维重建的丘脑表面光滑、形态逼真,清晰的显示了丘脑在标准立体定向空间中的位置,可直观显示,任意角度浏览.男性右侧丘脑体积为5998.17±170.08mm3,左侧为6200.53±195.24.mm3;女性右侧丘脑体积为5999.98±172.55mm3,左侧为6184.98±184.36mm3.结论 基于MRI的人脑结构数字化具有可行性,60岁以上组丘脑体积较60岁以下组明显缩小.     

中国人脑立体定向Vim核团数字化图谱的研制

目的 利用组织学和计算机技术构建MRI不可见靶点-丘脑腹内侧中间核(Vim)数字化图谱,以便为功能神经外科制定手术计划提供直观的参考依据.方法 对9例成年男性尸脑按标准立体定向系统行50μm冰冻切割,尼氏染色.在切片上对Vim进行识别、分割、提取、三维重建.结果 立体定向空间内Vim核团矢状面大致为楔形,长轴向外侧偏离Z轴约20°.核团的坐标三维范围:X轴方向为18.4～9.2mm;Y轴方向为-8～-2mm;z轴方向0～8mm.左、右侧Vim核团体积分别为(229.65±15.93)mm3和(233.34±15.16)mm3.结论 三维重建的Vim表面光滑、形态逼真,清晰地显示了Vim核团在标准立体定向空间中的位置和大小,并能任意角度浏览,使实现Vim可视化具有可行性.     

中国人脑丘脑底核MRI立体定向解剖学研究

目的 研究中国人脑丘脑底核(STN)MRI立体定向三维靶点坐标和体积,为帕金森病立体定向手术提供解剖学数据.方法 采集健康中国自愿者人脑MRI图像120例,在标准立体定向空间内测量STN的质心坐标和体积,并对比研究不同年龄组间数值差异及其与年龄问的相关性.结果 STN质心坐标与年龄存在相关性(P＜0.05),左侧STN体积＞右侧,STN体积与年龄呈负相关(P＜0.05).结论 中国人脑STN三维靶点坐标和体积能够在MRI立体定向空间下准确获取,并为临床实际应用奠定基础.     

中国人脑黑质立体定向数字化解剖图谱的研究

目的探讨建立立体定向MRI黑质数字化、可视化图谱的可行性,为立体定向功能神经外科提供解剖学依据。方法健康中国自愿者150人,在标准的立体定向空间内进行全脑扫描,测量黑质体积。选取其中30例利用eFilm软件对黑质中心点坐标进行测量。随机选取1名自愿者,利用其成像数据,对黑质进行三维重建,并对其进行可视化、数字化处理。结果黑质的平均体积左侧为（327．26±24．19）mm3,右侧为（307．28±25．11）mm3,左右侧黑质的体积存在显著性差异（P〈0．05）。黑质中央截面的中心点坐标X、Y、Z分别为（8．45±0．69）mm、（一4．36±0．50）mm和（一9．47±0．80）mm,左右侧黑质的中心点坐标无显著性差异（P〉0．05）,性别之间黑质的中心点坐标亦无显著性差异（P〉0．05）。结论建立立体定向MRI黑质数字化、可视化图谱是可行的。     

人脑丘脑底核磁共振可视化三维重建初探

丘脑底核(STN)脑深部电刺激(DBS)是治疗帕金森病的有效方法[1-2].随着临床MRI技术的发展,对STN的MRI三维重建越来越得到学者们的重视[3].三维重建不仅可以提供二维断画的各种信息还可以提供空间图像及靶点和周围结构的空间形态关系.本文探讨MRI对STN进行三维重建的技术,并对其参数进行测量.     

人脑丘脑底核磁共振可视化三维重建初探

丘脑底核(STN)脑深部电刺激(DBS)是治疗帕金森病的有效方法[1-2].随着临床MRI技术的发展,对STN的MRI三维重建越来越得到学者们的重视[3].三维重建不仅可以提供二维断画的各种信息还可以提供空间图像及靶点和周围结构的空间形态关系.本文探讨MRI对STN进行三维重建的技术,并对其参数进行测量.     

人脑丘脑底核磁共振可视化三维重建初探

丘脑底核(STN)脑深部电刺激(DBS)是治疗帕金森病的有效方法[1-2].随着临床MRI技术的发展,对STN的MRI三维重建越来越得到学者们的重视[3].三维重建不仅可以提供二维断画的各种信息还可以提供空间图像及靶点和周围结构的空间形态关系.本文探讨MRI对STN进行三维重建的技术,并对其参数进行测量.     

Direct stereotactic targeting of the ventrointermediate nucleus of the thalamus based on anatomic 1.5-T MRI mapping with a white matter attenuated inversion recovery (WAIR) sequence

BackgroundThe ventrointermediate nucleus (Vim) of the thalamus is still considered “invisible” on current magnetic resonance imaging (MRI), requiring indirect methods based on stereotactic atlases for estimation of its location. Direct visualization of Vim is desirable to improve targeting.ObjectiveTo evaluate the ability of Inversion-Recovery 1.5-T MR images to produce high-resolution, anatomical depiction of the thalamus suitable for direct Vim targeting.MethodsTwenty patients with essential tremor or tremor associated with Parkinson’s disease received Vim deep brain stimulation (DBS). Fahn-Tolosa-Marin and Unified Parkinson’s Disease Rating Scale (UPDRS) tremor scores were assessed pre- and postoperatively. Preoperative stereotactic 1.5-T MR images of the thalamus were acquired using a White Matter Attenuated Inversion Recovery (WAIR) sequence. Thalamic nuclei were manually contoured on the basis of spontaneous MRI contrasts; labeling relied on 3D identification from stereotactic books and in-house ex vivo 4.7-T microscopic MRI atlas. Vim was then directly probed for electrophysiological confirmation and determination of the optimal site for electrode placement.ResultsThe shape, spatial orientation, and signal contrast of Vim as depicted on our WAIR images were similar to those observed on the Schaltenbrand and Bailey atlas, as well as in our high-field MRI atlas. These images were successfully used for pure direct Vim targeting: at the last follow-up (median = 46.3 months), the average tremor score improved from 3.80 preoperatively to 0.50 postoperatively (on stimulation; P < 0.01).Conclusion1.5-T MRI with WAIR sequence provides high-quality images of Vim suitable in DBS surgery, for accurate preoperative planning, direct targeting and anatomic analysis.     

Validation of a fiducial-based atlas localization method for deep brain stimulation contacts in the area of the subthalamic nucleus

Differences in the location of active contacts with respect to the subthalamic nucleus (STN) may account for much variability in motor, psychiatric and cognitive responses to deep brain stimulation (DBS) in Parkinson disease (PD) patients. Because localization of STN based on hypointensity in T2-weighted MR images is unreliable and further limited by artifacts from the metal electrodes, we developed and validated a method to transform brain images into stereotactic space [Mai JK, Assheuer J, Paxinos G. Atlas of the Human Brain, 2nd ed. San Diego: Elsevier Academic; 2004] using reliably-identified anatomic fiducials identified in high-resolution T2-weighted pre-operative MR images. Average intraclass correlation between two raters for 29 PD patients was 0.93 for those fiducials used to define the atlas. Accuracy of the registration was tested by comparing the rater-identified centers of the red nuclei with their predicted locations from the fiducial-based atlas transformation. Mean discrepancies were 0.1, 0.9, and 0.0mm (x, y, z) with standard deviations of 0.9, 0.7 and 1.1mm, respectively. Because post-operative determination of contact location with respect to the STN is necessary due to possible shifting of electrodes during surgical placement, we identified active contacts on post-operative CT images and transformed their locations into stereotactic space. This method provides an accurate and reliable means for STN DBS contact localization.     

Subthalamic nucleus stimulation in Parkinson’s disease

OBJECTIVES: 1 - To assess the anatomical localization of the active contacts of deep brain stimulation targeted to the subthalamic nucleus (STN) in Parkinson's disease patients. 2 - To analyze the stereotactic spatial distribution of the active contacts in relation to the dorsal and the ventral electrophysiologically-defined borders of the STN and the stereotactic theoretical target. METHODS : Twenty-eight patients underwent bilateral high-frequency stimulation of the STN (HFS-STN). An indirect anatomical method based on ventriculography coupled to electrophysiological techniques were used to localize the STN. Clinical improvement was evaluated by Unified Parkinson's Disease Rating Scale motor score (UPDRS III). The normalized stereotactic coordinates of the active contact centres, dorsal and ventral electrophysiologically-defined borders of the STN were obtained from intraoperative X-rays images. These coordinates were represented in a three-dimensional stereotactic space and in the digitalized atlas of the human basal ganglia. RESULTS: HFS-STN resulted in significant improvement of motor function (62.8%) in off-medication state and levodopa-equivalent dose reduction of 68.7% (p < 0.05). Most of the active contacts (78.6%) were situated close to (+/- 1.6 mm) the dorsal border of the STN (STN-DB), while 16% were dorsal and 5.4% were ventral to it. Similar distribution was observed in the atlas. The euclidean distance between the STN-DB distribution center and the active contacts distribution center was 0.31 mm, while the distance between the active contacts distribution center and the stereotactic theoretical target was 2.15 mm. Most of the space defined by the active contacts distribution (53%) was inside that defined by the STN-DB distribution. CONCLUSION: In our series, most of the active electrodes were situated near the STN-DB. This suggests that HFS-STN could influence not only STN but also the dorsal adjacent structures (zona incerta and/or Fields of Forel).     

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。     

Bilateral subthalamic nucleus deep brain stimulation for advanced PD: correlation of intraoperative MER and postoperative MRI with neuropathological findings.

This postmortem study correlated intraoperative subthalamic nucleus (STN) deep brain stimulation (DBS) placement and postoperative magnetic resonance imaging (MRI) with autopsy findings in a patient who died suddenly 4 days postoperatively from a pulmonary embolism. The study demonstrates that (1) MRI stereotactic localization combined with microelectrode recording (MER) is an accurate way to target STN; (2) multiple MER tracts do not cause significant injury to the brain; and (3) postoperative MRI accurately demonstrates location of the DBS electrodes.     

Anatomical alterations of the subthalamic nucleus in relation to age: a postmortem study.

The subthalamic nucleus (STN) is currently the preferred target for chronic electrical high-frequency stimulation in Parkinson's disease. Anatomical determination of the exact position of the STN in the individual patient, using magnetic resonance imaging, remains cumbersome, whereas calculation of the target using a stereotactic atlas bypasses patient interindividual variations in the exact delineation of the STN. The aim of this study was to demonstrate variations in shape and position of the STN during life. In this anatomopathological study, a method was applied to localize the STN in reference to the anterior commissure-posterior commissure line (AC-PC line) in 12 postmortem brains of patients who died of non-neurological diseases. Their age varied from 29 to 84 years. Centers and borders of the STN were macroscopically measured in three spatial orthogonal planes in relation to the AC-PC line, and verified by light microscopy. The AC-PC distance remains almost constant during life (24.4 mm; SD 3.58). With increasing age, the center of the STN tends to move 3.9 mm cranially, 2.6 mm laterally, and 0.2 mm anteriorly. This last result also differs from the position mentioned in the stereotactic brain atlases. The form of the STN also changes. During life, the STN becomes wider in the mediolateral direction and smaller in the superior-inferior and anterior-posterior direction. The shape and spatial position of the STN also change during life. These changes should be taken into account during target determination in deep brain stimulation procedures in Parkinson's disease.     

Stereotactic neurosurgical planning, recording, and visualization for deep brain stimulation in non-human primates

Methodologies for stereotactic neurosurgery and neurophysiological microelectrode recordings (MER) in non-human primate research typically rely on brain atlases that are not customized to the individual animal, and require paper records of MER data. To address these limitations, we developed a software tool (Cicerone) that enables simultaneous interactive 3D visualization of the neuroanatomy, neurophysiology, and neurostimulation data pertinent to deep brain stimulation (DBS) research studies in non-human primates. Cicerone allows for analysis of co-registered magnetic resonance images (MRI), computed tomography (CT) scans, 3D brain atlases, MER data, and DBS electrode(s) with predictions of the volume of tissue activated (VTA) as a function of the stimulation parameters. We used Cicerone to aid the implantation of DBS electrodes in two parkinsonian rhesus macaques, targeting the subthalamic nucleus in one monkey and the globus pallidus in the other. Cicerone correctly predicted the anatomical position of 79% and 73% of neurophysiologically defined MER sites in the two animals, respectively. In contrast, traditional 2D print atlases achieved 61% and 48% accuracy. Our experience suggests that Cicerone can improve anatomical targeting, enhance electrophysiological data visualization, and augment the design of stimulation experiments.