Oblique transcorporeal approach to anteriorly located lesions in the cervical spinal canal

Summary The technique of obliquely drilling out the postero-lateral part of the cervical vertebral bodies is described. It uses the antero-lateral (retro carotico-jugular) approach to control and displace the vertebral artery postero-laterally and to expose the lateral aspect of the vertebral bodies. It provides, through a wide field and with minimal retraction of the carotid artery and the internal jugular vein, an extensive view of the anterior aspect of the spinal cord. It has already been used to treat 15 anterior lesions compressing the spinal cord including neurinomas and osteophytes.     

A Biotin–Avidin-Based Enzyme Immunoassay for βh-Endorphin

An avidin–biotin enzyme-linked immunosorbent assay (ELISA) is described for _h-endorphin (_h-EP). Microtiter plates coated with commercially available antibodies were used together with _h-EP tracer derivatives that were biotinylated in positions 24, 28, and 29 via a C₆ spacer arm. Nonspecific binding of biotinylated derivatives to the microtiter plates was blocked with a mixture of 1% casein and 10% ethanolamine in 0.1 M NaHCO₃. A sequential saturation procedure using a high-affinity antiserum in combination with an avidin–alkaline phosphatase complex matched the sensitivity of reported radioimmunoassays (RIAs), with a detection limit of 0.5 fmol/assay. The intra- and interassay coefficients of variation were 5 and 12%, respectively. Results obtained by ELISA and RIA showed good correlations (r = 0.95). The -EP concentration in extracted rat plasma after high-performance liquid chromatographic (HPLC) fractionation was determined by this method to be 1600 fmol/ml.     

Thalamic connections of the vestibular cortical fields in the squirrel monkey (Saimiri sciureus).

The afferent thalamic connections to cortical fields important for control of head movement in space were analysed by intracortical retrograde tracer injections. The proprioceptive/vestibular area 3aV, the neck-trunk region of area 3a, receives two thirds of its thalamic projections from the oral and superior ventroposterior nucleus (VPO/VPS), which is considered as the proprioceptive relay of the ventroposterior complex (Kaas et al., J. Comp. Neurol. 226:211-240, 1984). The parieto-insular vestibular cortex (PIVC, area retroinsularis, Ri) receives its main thalamic input from posterior parts of the ventroposterior complex and from the medial pulvinar. Anatomical evidence is presented that the posterior region of the ventroposterior complex is a special compartment within this principal somatosensory relay complex. The parietotemporal association area T3, mainly involved in visual-optokinetic signal processing, receives a substantial input from the medial, the lateral, and the inferior pulvinar. Dual tracer experiments revealed that about 5% of the thalamic neurons projecting to 3aV were spatially intermingled with neurons projecting to areas PIVC or T3. This spatial intermingling was distributed over small but numerous, circumscribed thalamic regions, called "common patches," which were found mainly in the intralaminar nuclei, the posterior group of thalamic nuclei, and the caudal parts of the ventroposterior complex. The "common patches" may indicate a functional coupling of area 3aV with the PIVC or area T3 on the thalamic level. In control experiments thalamic projections to the granular insula Ig and the anterior part of area 7, two cerebral structures connected with the vestibular cortical areas, were studied. Some overlap in the thalamic relay structures projecting to these areas with those projecting to the vestibular cortices was found. A quantitative evaluation of thalamic regions projecting to different cortical structures was performed by constructing so-called "thalamograms." A scheme was developed that describes the afferent thalamic connections by which vestibular, visual-optokinetic, and proprioceptive signals reach the vestibular cortical areas PIVC and 3aV.     

Primary cerebral neuroblastoma (neurocytoma) in adults

Summary We report a case of a third ventricular neuroblastoma (neurocytoma) in a 66 year old man. A stereotactic needly biopsy was performed to obtain a tissue diagnosis and was followed by total resection. We elected not to give radiation or chemotherapy and to follow the patient closely with serial CT scans. Presently, 48 months postoperatively, the patient is free of tumor by head CT scan and able to live independently. We reviewed the literature of primary cerebral neuroblastomas/neurocytomas occurring in adults (15 years of age) and found 32 cases. Our patient is the oldest of this group with a mean age of 32 ± 14 years (S.D.). The location of the 33 neoplasms was intraventricular in 17 cases (52%) and intraparenchymal in 16 cases. The male to female ratio was 2: 1. Of the 17 patients having a minimal follow-up period of 5 months (mean 51 months), five developed recurrences after 5 to 144 months (mean 50 months) compared to 12 patients without recurrence after a 6- to 72-month follow-up period (mean 52 months). Recurrences occurred statistically significantly more often in parenchymal neuroblastomas/neurocytomas than in intraventricular tumor locations.     

Retinal projections to the lateral posterior-pulvinar complex in intact and early visual cortex lesioned cats

In intact cats, it is generally considered that the lateral posterior-pulvinar complex (LP-pulvinar) does not receive direct retinal terminals, with the exception of the retino-recipient zone known as the geniculate wing. There is, however, some evidence that early lesions of the visual cortex can occasionally induce the formation of novel retinal projections to the LP nucleus. Given the importance of knowing the connectivity pattern of the LP-pulvinar complex in intact and lesioned animals, we used the B fragment of cholera toxin, a sensitive anterograde tracer, to reinvestigate the retinal projections to the LP-pulvinar in normal cats and in cats with early unilateral lesions of the visual cortex (areas 17 and 18). Immunohistochemical localization of the toxin was performed to show the distribution and morphology of retinofugal terminals. A direct bilateral but predominantly contralateral retinal projection reached the caudal portion of LPl and LPm in the form of patches located mainly along its dorsomedial surface and many scattered terminals. The distribution of retinal projections to LP-pulvinar in intact and operated cats did not differ. Contrary to what had been previously reported, we found no evidence for lesion-induced sprouting of retinal axons in these higher-order thalamic nuclei. Retinal input to the LP-pulvinar might modulate visual responses driven by primary visual cortex or superior colliculus.     

上部颈椎经颈前外侧手术入路的应用解剖

目的：为上部颈椎经颈前外侧手术入路提供解剖学基础。方法：在２０具固定成人尸体上，按手术入路逐层解剖，观测有关的血管、神经等结构及其毗邻关系。结果：入路有甲状腺上动脉、舌动脉、面动脉自颈外动脉不同高度发出，其中舌动脉与舌下神经；喉上动脉与喉上神经喉内支伴行关系有三种：甲状腺上动脉与喉上神经喉外支伴行关系有二种。结论：经颈前外侧手术入路具有显露充分，操作方便，可处理颈上部３个颈椎病变，具有推广价值。     

神经导航辅助眉弓锁孔入路量化研究及临床意义

目的:报道经眉弓锁孔入路对鞍区结构的显微外科解剖和显微技术。方法:在15例(30侧)经颈内动脉、椎动脉灌注红色乳胶的成人头标本上模拟经眉弓锁孔入路,借助手术显微镜(6~25倍)观察鞍区显微解剖结构,并在神经导航下量化Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ间隙面积,颈内动脉及分支、视神经长度。结果:眉弓锁孔入路对5间隙结构有很好暴露,通过第Ⅱ间隙打开Liliequist膜后可见基底动脉(BA)分叉,大脑后动脉(PCA),小脑上动脉(SCA)及其穿通血管和动眼神经出脑干处及其行程,各间隙面积Ⅰ(85.64±6.87mm2)、Ⅱ(46.62±5.34mm2)、Ⅲ(18.97±2.78mm2)、Ⅳ(49.27±4.86mm2)、Ⅴ(35.95±3.41mm2);颈内动脉眼段长(6.64±1.45mm),交通段长(3.35±0.46mm),脉络膜段长(3.75±0.67mm),仔细分离切断周围的蛛网膜小梁,充分游离血管及其分支,在视交叉后上方可充分显露大脑前动脉(ACA)A1、A2段,前交通动脉复合体及Heubner返支,A1长(22.12±3.65mm)。左侧视神经为(15.15±2.54mm),右(14.42±1.89mm)。结论:眉弓锁孔入路可对鞍区结构很好暴露,第Ⅰ间隙面积最大,Ⅰ、Ⅳ与入路方向一致,显露更为满意,通过Ⅱ间隙可观察Willis后环周围结构;处理鞍区肿瘤,以鞍区4个常规解剖间隙为主,联合第Ⅴ间隙可获得满意效果。     

Neurosurgical anatomy of the anterior interhemispheric approach for aneurysms of the anterior communicating artery (26.6.92)

Summary The anterior interhemispheric approach for aneurysms of the anterior communicating artery was studied in ten cadavers. This approach presents several advantages over the pterional approach widely used in neurosurgery. It allows direct access to the region of the anterior communicating artery complex with minimal retraction of the brain and preservatioin of the olfactory tract and the gyrus rectus.

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Bases anatomiques de l'abord inter-hémisphérique antérieur lors de la chirurgie des anévrysmes de l'artère communicante antérieure

Résumé Ce travail concerne l'abord neurochirurgical des anévrysmes de l'artére communicante antérieure par voie frontale interhémisphérique. L'étude anatomique a été réalisée sur dix sujets. Cette exposition possède de nombreux avantages comparée à la voie ptérionale habituelle : voie d'abord reduite médiane permettant une visualisation directe et symétrique du complexe artériel de l'artére communicante antérieure ; avec le moindre manipulation et retraction du cerveau en respectant les voies olfactives et le gyrus rectus.

     

乙状窦后进路内窥镜手术解剖学研究

目的：为乙状窦后进路相关内窥镜手术提供解剖学依据。方法：测量30例干颅骨表面标志位置关系，准确定位乙状窦后进路骨窗；利用10具甲醛固定成年头标本模拟内窥镜下乙状窦后进路，验证其可行性。结果：(1)以星点至乳突点连线中点为中心作直径2．0cm的骨窗适于暴露桥脑小脑角区结构；(2)内镜下乙状窦后进路可在尽量减少压迫小脑的情况下充分暴露桥脑小脑角区神经、血管等重要结构。结论：精确定位乙状窦后进路骨窗能够最大限度减少牵托小脑，对临床开展锁孔手术有指导意义。     

内耳门周结构对内镜下脑桥小脑三角区手术的影响

目的：研究内耳门周结构对颞骨径路内镜下处理脑桥小脑三角区病变手术的影响，为临床开展相应手术提供参考。方法：在20例40侧成人尸头上模拟颞骨径路内窥镜手术，观察小脑下前动脉及内耳门后唇的变异，了解其对内窥镜导入及其手术的影响。结果：内耳门后唇隆起超过面神经脑桥小脑角段1／3以上者占27．5％(11侧)。小脑下前动脉在Ⅶ、Ⅷ脑神经外侧成袢者占22．5％(9侧)。内耳门后唇隆起合并小脑下前动脉袢在Ⅶ、Ⅷ脑神经之外侧者占7．5％(3侧)。结论：当内耳门后唇隆起超过面神经脑桥小脑角段1／3或小脑下前动脉弓在Ⅶ、Ⅷ脑神经之前时将对内窥镜导入有阻碍，当两种情况合并存在时要将内窥镜导入脑桥小脑三角区相当困难，不宜采用此种手术方式。