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101.
乙状窦后进路内窥镜手术解剖学研究   总被引:2,自引:1,他引:2  
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。  相似文献   
102.
Placenta from an extrauterine abdominal pregnancy was examined after a 37-week healthy infant gestation. The placenta, with its fetal surface down and maternal surface up, protruded from the pelvic area to peritoneal cavity in the wall of the amniotic sac containing fetus. The placenta was implanted under the thin subperitoneal layer of maternal tissue completely covered by peritoneal serosa and was formed by several small lobes connected by intramembranous placental vessels. Insertion of the trivascular umbilical cord was velamentous. Partially remodeled arteries infiltrated by intermediate trophoblast and frequent veins directly communicating with the placental intervillous space were identified in the subperitoneal maternal tissue. The term "placenta accreta" is appropriate in this case because villi in the basal plate implanted directly in the maternal subserosal connective tissue without intervening decidua.  相似文献   
103.
Summary The authors report the results of a series of dissections and anatomic sections of the fronto-basal region of the brain and of the anterior cranial fossa in human cadavers. The constant presence of an arachnoidal cistern above the olfactory nerve was verified. The arachnoid separates from the pial membrane and forms a bridge with the ventral part of the olfactory bulb and tract, from the lateral edge of the olfactory sulcus to the medial edge of the gyrus rectus. The cistern is wide in its anterior portion, between the gyrus rectus and the olfactory bulb, and is reduced to a virtual slit in its posterior portion where the tract is lodged in the olfactory sulcus. The olfactory nerve can be separated without damaging fronto-basal arachnoidial adhesions over several centimeters. Dissection of this region after intravascular injection of colored media shows the constant presence of an artery destined to the olfactory bulb and tract. It originates either from the lateral surface of the anterior cerebral a. (segment A2), or from the medial fronto-basal a., and consistently provides terminal branches in front of the olfactory trigone in the medial olfactory sulcus. At their ventral extremity, the olfactory structures are therefore vascularised independently for several centimeters, from the lower face of the frontal lobe. The independent vascularisation of the olfactory nerve, the tenuous and easily detachable adhesions, and the actual presence of a true arachnoidal cistern all contribute to enabling surgical techniques which conserve olfactory function during anterior approaches.
Vascularisation du nerf olfactif. Rapports méningés et applications chirurgicales
Résumé Les auteurs rapportent les résultats d'une série de dissections et de coupes de la région fronto-basale de l'encéphale et de la fosse crânienne antérieure sur sujets cadavériques. La présence constante d'une citerne arachnoïdienne au dessus du n. olfactif a été vérifiée. L'arachnoïde se sépare du feuillet pial et passe en pont à la partie ventrale du bulbe et du tractus olfactifs, du bord latéral du sillon olfactif au bord médial du gyrus rectus. La citerne est large dans sa portion antérieure, entre le gyrus rectus et le bulbe olfactif, se réduit à une fente virtuelle postérieure lorsque le tractus se loge dans le sillon olfactif. Le n. olfactif peut être séparé sans dommage des adhérences arachnoïdiennes fronto-basales sur quelques centimètres. La dissection de cette région, après injection intravasculaire de masses colorées montre, de façon originale, la présence constante d'une artère destinée au tractus et au bulbe olfactifs. Elle naît soit de la face latérale de l'a. cérébrale antérieure (segment A2), soit de l'a. fronto-basale médiale, pour donner ses branches terminales toujours en avant du trigone olfactif dans le sillon orbitaire médial. Sur quelques centimètres à leur extrémité ventrale, les structures olfactives ont donc une vascularisation indépendante de la face inférieure du lobe frontal. L'indépendance vasculaire du n. olfactif, des adhérences ténues, facilement détachables, et la réalité vérifiée d'une véritable citerne arachnoïdienne permettent d'imaginer des techniques conservatrices de la fonction olfactive utilisées dans plusieurs indications de la chirurgie de la fosse crânienne antérieure.
  相似文献   
104.
Functionally and anatomically, the orbicularis oculi (OO) muscle can be subdivided in a pretarsal, a preseptal, and an orbital portion. In the rhesus monkey, fluorescent and neuronal retrograde tracing experiments were performed in the pretarsal or the orbital portion of the OO muscle, or both, using fast blue, diamidino yellow, and wheat germ agglutinin-horseradish peroxidase as tracers. The preseptal portion was not investigated because of close anatomical relationships to the other portions. It was found that motoneurons innervating the OO muscle are located exclusively within the intermediate subnucleus of the motor facial nucleus. The upper pretarsal motoneurons show a specific distribution in the dorso-rostral border area of the intermediate subnucleus, representing a dome-like organization, while lower pretarsal motoneurons are situated more ventrally in the adjacent area. The pretarsal motoneurons are all located dorsally in the rostral half and the upper part of the caudal half of the intermediate subnucleus. The upper pretarsal portion is subserved by about one third of the total intermediate motoneuron population. The size of the upper pretarsal motoneurons is similar to that of the motoneurons of the lower pretarsal portion of the OO muscle and falls, for the vast majority, into the large motoneuronal range. Motoneurons belonging to the upper and lower orbital portions are located ventrally and are more randomly distributed in the rostral half of the intermediate subnucleus. The size of orbital motoneurons varies from small to large. The large fraction of pretarsal motoneurons may reflect the specific function of the upper pretarsal portion during rapid and highly coordinated movements of the eyelids in different types of blinking. Received: 18 September 1997 / Accepted: 13 March 1998  相似文献   
105.
The authors present a study of the intrinsic anatomy of the gluteus medius m. and of its innervation through the caudal branch of the superior gluteal n. The existence of an intramuscular tendon in the thickness of the gluteus medius was constantly prooved in 40 muscles. The relations of the intrinsic fibrous structure of the muscle and its innervation were studied. The authors deduce from that the topography of a gluteus medius incision, with respect to a safety area towards its innervation, which leads to an exposure of the acetabulum that is satisfying and gives opportunities of a sound repair after the surgery of the hip joint through the transgluteal approach. They propose the anterior hemimyotomy of the gluteus medius m designation.
Bases anatomiques de l'abord transglutéal de la hanche par hémimyotomie antérieure du muscle moyen fessier
Résumé Les auteurs présentent une étude de l'anatomie intrinsèque du m. moyen fessier (MF) et de son innervation par le rameau caudal du n. glutéal supérieur (NGS). 40 muscles ont été étudiés. L'existence d'une lame tendineuse dans l'épaisseur du MF a été constamment mise en évidence. Les rapports entre les éléments de l'architecture fibreuse intrinsèque du muscle et son innervation ont été étudiés. Les auteurs en déduisent la topographie d'une incision du MF respectant une zone de sécurité vis à vis de son innervation, procurant une exposition acétabulaire satisfaisante et des possibilités de réparation solide après chirurgie de l'articulation coxo-fémorale par voie d'abord transglutéale, et proposent la dénomination hémimyotomie antérieure du MF.
  相似文献   
106.
Summary A posterior fossa tumour in a 3 year old child is presented with characteristic histological, ultrastructural and immunohistochemical features of rhabdoid tumour. Many tumour cells contained cytoplasmic eosinophilic hyaline inclusions. Ultrastructurally concentric whorls of 10 nm intermediate filaments were identified. Immunohistochemical staining disclosed vimentin, cytokeratin and epithelial membrane antigen positivity. Renal and extrarenal rhabdoid tumours have been well documented but a primary rhabdoid tumour of the brain is extremely rare. Additional ultrastructural features seen were tubular crystalline inclusions in endoplasmic reticulum and abnormal large mitochondria.  相似文献   
107.
内窥镜下第三脑室手术的应用解剖   总被引:1,自引:4,他引:1  
目的 :为神经内窥镜下进行第三脑室手术提供解剖学资料。方法 :对 2 1例成人尸头固定标本进行第三脑室的解剖观察和测量 ,对 9具新鲜尸头进行经室间孔入路神经内窥镜下第三脑室的解剖学观察。结果 :室间孔长径、宽径为 (5 .4± 1.2 )mm、(2 .7± 0 .9)mm ,中间块长径、宽径为 (6.8± 2 .3 )mm、(3 .8± 1.0 )mm ,前后联合间距 (2 1.8± 2 .1)mm ,前、后联合到中间块为 (6.3± 0 .8)mm、(8.8± 1.3 )mm ,前后联合中点处第三脑室高度 (13 .8± 1.4)mm ,室间孔下、后联合前及中间块上、下第三脑室宽度分别为 (6.3±2 .2 )mm、(4 .9± 1.8)mm、(3 .4± 1.6)mm和 (4 .3± 1.8)mm ,中间块上、下最小高度为 (4 .4± 1.3 )mm和(4 .3± 1.3 )mm。内窥镜可较清晰显示第三脑室内结构 ,但中间块可影响显露。结论 :内窥镜下经室间孔入路进行第三脑室手术有一个理想的操作空间。  相似文献   
108.
目的:探讨相关解剖定位标志在经单鼻孔-蝶窦入路垂体腺瘤显微外科手术中的应用。方法:62例垂体腺瘤经单鼻孔-蝶窦入路显微手术,术中根据蝶嵴、蝶窦开口、蝶窦中隔、鞍底隆凸等解剖标志进行定位。结果:蝶嵴是术中确认手术入路中线的可靠标志,蝶窦开口是蝶窦前壁的重要标志,鞍底隆凸可作为蝶窦腔内鞍底定位标志。62例术中依靠相关解剖标志,均准确定位蝶窦及鞍底,未出现偏差。肿瘤全切除52例,次全切除5例,大部分切除4例。1例部分切除,无死亡病例。结论:熟悉相关解剖标志,有助于该术式的准确定位,从而安全实施手术。  相似文献   
109.
The effect of externally applied mechanical stress was investigated by thin section electron microscopy of the microvessels in the unaffected palmar fascia in the carpal tunnel syndrome and in patients with Dupuytren's contracture before and after application of a continuous elongation device. In the unaffected palmar fascia the microfilaments of the endothelial cells were connected to a few adherens junctions and focal contacts; stress fibres were absent. In the cord of Dupuytren's disease the microfilaments were increased in quantity. The length ratios of the connections with the lateral and basal cell membrane were significantly higher than in the control group and increased to an even greater extent in the continuously extended fascia. Stress fibres appeared in the endothelial cells of postcapillary venules in the nonextended cord and in the endothelium of both arterioles and venules after extension elongation. The numerous intermediate filaments and the rare microtubules remained unchanged in the endothelial cells of all palmar fasciae analysed. In the endothelial cells of the microvessels the mechanical stress applied from outside mainly affected the contractile component of the cytoskeleton.  相似文献   
110.
目的:总结经蝶窦进路显微手术治疗巨大垂体瘤的经验。方法:经蝶窦进路显微手术治疗直径在30mm以上的巨大垂体瘤58例。结果:58例中,镜下全切除者52例、大部分切除者6例,经手术治疗后症状均有不同程度的改善。1例于术后1个月死于垂体危象。余57例患者术后随访2~5a,复发5例均经再次手术治愈。结论:巨大垂体腺瘤的手术治疗仍以经蝶窦进路为首选。  相似文献   
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