小脑下后动脉在枕骨大孔区的解剖学研究

目的对颅后窝枕骨大孔区小脑下后动脉进行观察与测量,并探讨其临床意义。方法选取成人颅底标本15例,观察枕骨大孔区小脑下后动脉位置、走行、毗邻关系及其分布,测量相关数据并进行统计学处理。结果颅后窝枕骨大孔区小脑下后动脉左右两侧起始部外径:左侧为1.32~1.49 mm,平均(1.41±0.05)mm;右侧为1.27~1.49 mm,平均(1.39±0.07)mm,左右管径比较差异无统计学意义(P>0.05);小脑下后动脉走行呈“S”形,与第Ⅸ、Ⅹ、Ⅺ对脑神经的位置关系密切。结论小脑下后动脉在枕骨大孔区起点走行、分布具有特有的解剖特点,在临床中枕骨大孔区小脑下后动脉相关疾病的手术时应避免医源性损伤。     

小脑下前动脉与前庭蜗神经关系的解剖学观察

目的观察人小脑下前动脉的走行和与前庭蜗神经间的解剖学位置关系。方法对20具甲醛固定的人尸颅进行测量,重点观察了小脑下前动脉及主要分支的走行和与前庭蜗神经间的位置关系。结果小脑下前动脉出现率为100％,回返穿通动脉为100％,小脑下前动脉袢为100％。回返穿通动脉位于面神经、前庭蜗神经之间有32例(80％)。前庭蜗神经血管接触率为95％,2支或2支以上血管与前庭蜗神经接触的有20例,占50％。结论实验结果为桥脑小脑角手术提供解剖学资料。     

Intracranial course and relations of the hypoglossal nerve: An anatomic study

This anatomic study describes the course and intracranial relations of the hypoglossal n. in 32 cadavers. The rootlets of the nerve emerged as a fan-shaped distribution (23.44%) or in two bundles (76.56%) and converged towards the hypoglossal canal in the subarachnoid space before piercing the dura mater. In 76.57% of cases the rootlets pierced the dura mater in two separate apertures, less commonly through the same aperture (21.87%), and in rare cases through three individual apertures, as in one of our cases. The distance between the two apertures varied from 0.6 mm to 8.7 mm. Commonly, the two bundles converged together and left the skull through one foramen in the skull. However, in some cases (28.12%), the hypoglossal canal was divided in two by a small bony spicule. In 23.45% of cases the initial course of the posterior inferior cerebellar a. (PICA) passed between the two bundles of the hypoglossal n. before ascending towards the lateral border of the fourth ventricle.     

小脑动脉与三叉神经根毗邻关系的应用解剖

目的　观察小脑动脉的起始位置、行程特点及其与三叉神经根的毗邻关系,为三叉神经微血管减压术提供解剖学依据。 方法　采用12个福尔马林固定的成人头部标本,在手术显微镜下分别解剖小脑上动脉、小脑下前动脉、小脑下后动脉及三叉神经等结构。观察相关动脉、神经的位置、走行特点,测量上述动脉的起始段外径及其与三叉神经根最近距离等相关数据。 结果　共发现小脑上动脉27支,2支压迫三叉神经根,5支与神经根接触,其余无接触压迫者与三叉神经的最近距离为（3.87±1.58） mm（0.55~6.30 mm）;小脑下前动脉23支,压迫神经根1例,与之接触者2例,其余20支小脑下前动脉与三叉神经根最近距离为（4.67±1.77）mm（2.65~9.50 mm）;小脑下后动脉21支,与三叉神经根最近距离为（17.12±3.86） mm（10.45~25.70 mm）,未发现与之接触或压迫者。 结论　小脑上动脉与三叉神经关系密切,常与三叉神经接触并压迫神经,成为三叉神经痛发生的主要结构。小脑下前动脉与三叉神经相距稍远,也可与三叉神经接触或压迫神经。小脑下后动脉与三叉神经相距较远,但偶尔也会压迫三叉神经根导致三叉神经痛。     

小脑动脉与三叉神经根毗邻关系的应用解剖

目的　观察小脑动脉的起始位置、行程特点及其与三叉神经根的毗邻关系,为三叉神经微血管减压术提供解剖学依据。 方法　采用12个福尔马林固定的成人头部标本,在手术显微镜下分别解剖小脑上动脉、小脑下前动脉、小脑下后动脉及三叉神经等结构。观察相关动脉、神经的位置、走行特点,测量上述动脉的起始段外径及其与三叉神经根最近距离等相关数据。 结果　共发现小脑上动脉27支,2支压迫三叉神经根,5支与神经根接触,其余无接触压迫者与三叉神经的最近距离为（3.87±1.58） mm（0.55~6.30 mm）;小脑下前动脉23支,压迫神经根1例,与之接触者2例,其余20支小脑下前动脉与三叉神经根最近距离为（4.67±1.77）mm（2.65~9.50 mm）;小脑下后动脉21支,与三叉神经根最近距离为（17.12±3.86） mm（10.45~25.70 mm）,未发现与之接触或压迫者。 结论　小脑上动脉与三叉神经关系密切,常与三叉神经接触并压迫神经,成为三叉神经痛发生的主要结构。小脑下前动脉与三叉神经相距稍远,也可与三叉神经接触或压迫神经。小脑下后动脉与三叉神经相距较远,但偶尔也会压迫三叉神经根导致三叉神经痛。     

Pathologic Reappraisal of Wallenberg Syndrome: A Pathologic Distribution Study and Analysis of Literature

Background

Wallenberg syndrome was first reported by Adolf Wallenberg as arising due to the obstruction of the posterior inferior cerebellar artery (PICA), which caused an infarct in the lateral medulla oblongata (MO).

Method

This study was carried out on brain tissue from 2 patients with typical Wallenberg syndrome and 10 autopsy cases without central nervous system disturbances.

Results

Patient 1 exhibited the 3 major neurological symptoms of right crossed sensory disturbance, right cerebellar ataxia and bulbar palsy. There was the pathological obstruction of the right vertebral artery (VA). Regarding the histopathlogical distribution, the infarct extended on the right side to the lateral spinothalamic tract, nucleus of the spinal tract of the trigeminal nerve, spinal tract of the trigeminal nerve, inferior cerebellar peduncle, spinocerebellar tract and nucleus ambiguous. Moreover, a clear infarct in the left lateral MO was pathologically identified, but pathological obstruction of the left PICA or left VA could not be found. The left cerebellar ataxia and bulbar palsy were observed among these 3 major symptoms. Patient 2 showed the 3 major symptoms of right crossed sensory disturbance, right cerebellar ataxia and bulbar palsy. A pathological luminal occlusion was identified in the right PICA. Regarding the histopathological lesion, the infarct disturbed on the right side the lateral spinothalamic tract, nucleus of the spinal tract of the trigeminal nerve, spinal tract of the trigeminal nerve, spinocerebellar tract, inferior cerebellar peduncle and nucleus ambiguus.

Conclusion

Based on our investigation of pathological lesions using our 2 autopsies, we suggest calling the cases that satisfy the following 3 criteria “definite pathologic Wallenberg syndrome”: i) identifiable pathological obstruction of the PICA or VA; ii) infarction in the lateral MO based on PICA or VA obstruction; and iii) a 1-to-1 correspondence between clinical symptoms and neuropathological lesions.     

乙状窦后入路的应用解剖学研究

目的　为乙状窦后入路手术提供解剖学依据。方法　对 2 0个成人颅骨标本乙状窦后入路手术骨窗的确定、开窗范围的大小进行观测。 15个成人尸头乙状窦后入路开窗显露桥小脑三角区域的结构 ,测量骨窗至三叉神经、面神经、前庭蜗神经、舌咽神经和小脑下前动脉袢的距离。结果　顶切迹至乳突尖连线中点向后 2 6 38± 3 95mm作为骨窗的中点 ,以该点为圆心 ,画出半径为 2 0mm的圆 ,该圆形区域与乙状窦不重叠。骨窗至三叉神经、面神经、前庭神经、舌咽神经穿硬脑膜和小脑下前动脉袢处的距离分别为 5 6 6 3± 4 5 5mm、4 7 2 3± 3 6 9mm、4 5 91± 3 99mm、4 3 73± 4 0 1mm、4 5 95± 3 77mm。结论　顶切迹至乳突尖连线中点向后2 6 38± 3 95mm处为乙状窦后入路手术开放骨窗的中点 ,骨窗的大小控制在半径为 2 0mm的圆形区内较为理想 ,手术中应注意保护桥小脑三角区域的有关结构。     

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。     

腹腔镜下小儿腹股沟内环口周围的应用解剖学研究

目的　为腹腔镜下小儿腹股沟斜疝修补术提供解剖学依据。 方法　对16具（32侧）经防腐处理的小儿尸体标本内环口周围血管神经进行观测。 结果　（1）髂腹下神经与腹壁下动脉在腹前壁的交点与内环口上缘的距离：男左侧为（16.77±1.36）mm,男右侧为(17.77±2.39)mm;女左侧为(16.41±2.23) 　mm,女右侧为（15.81±0.57）mm。（2）髂腹下神经与腹壁下动脉的夹角：男左侧为(107.75±11.59)°,男右侧为（106.29±8.87)°,女左侧为（106.42±9.46)°,女右侧为(110.23±9.42)°。各测量数据在性别间差异无统计学意义（P >0.05）,各测量数据在双侧无显著性差异（P>0.05）。 结论　（1）在腹前壁髂腹下神经与腹壁下动脉之间有一个没有神经和血管的“安全区域”,该区可为IPOM手术中腹腔镜下补片固定提供足够的安全范围。（2）以腹壁下动脉为参考标志,可减少髂腹下神经的损伤,减少慢性疼痛的发生率。     

腹腔镜入路骶神经电刺激器植入的解剖学特点及其临床意义

目的　讨论腹腔镜下骶前方植入骶神经电刺激电极手术入路解剖及手术可行性。 方法　在20具成人尸体标本上模拟腹腔镜下显露骶骨前第2~4骶神经前支手术,观察骶骨前方第2~4骶神经前支的形态特征和骶孔周围可能损伤重要血管的区域。 结果　第2~4骶神经前支出骶前孔至汇成骶丛的长度：S2左(32.62±3.15) mm,右(31.46±3.28) mm;S3左(21.96±2.59) mm,右(20.61±3.14) mm;S4左(15.04±1.64) mm,右(16.09±1.38) mm。骶外侧动脉的脊支动脉进入骶前孔的方位主要为内上象限。臀下动脉穿过神经时比较偏外侧靠近神经汇合处。骶椎旁静脉在第2~4骶前孔处与骶外侧动脉伴行,脊支静脉出骶前孔的位置与动脉一致。 结论　骶骨前方第2~4骶神经前支游离的长度能够达到硬膜外型骶神经电刺激器电极植入的要求。手术中骶前孔内侧为血管易损伤的危险区域。     

Localization of the supraorbital,infraorbital, and mental foramina using palpable,bony landmarks

The purpose of this study was to locate the infraorbital, supraorbital, and mental foramina by using palpable anatomical landmarks that are conducive to surgical use. Fourteen embalmed cadavers (27 sides) were dissected to expose the supraorbital, infraorbital, and mental foramina. Measurements were made from the lateral orbital rim at the zygomaticofrontal (ZF) suture to both the supraorbital and infraorbital foramina. The distance from the inferior orbital rim at the zygomaticomaxillary (ZM) suture to both foramina was also measured. The distance to the mental foramen was measured from the angle and the inferior border of the mandible. The supraorbital foramen was located 26.2 ± 2.8 mm medial and 13.5 ± 3.7 mm superior to the ZF suture. The infraorbital foramen was located 23.8 ± 3.1 mm medial and 30.9 ± 3.8 mm inferior to the ZF suture, on average. Vertical measurements made from the ZM suture to the supraorbital foramen averaged 34.4 ± 3.6 mm and from the ZM suture to the infraorbital foramina averaged 7.6 ± 2.2 mm. The mental foramen was 64.2 ± 6.4 mm medial to the angle of the mandible and 12.9 ± 1.6 mm superior to the inferior border of the mandible. This study provides data that may be useful in predicting the location of the supraorbital, infraorbital, and mental foramina using palpable landmarks. These data may be particularly helpful for surgery in patients with missing teeth or fractures of the maxillary bone. Clin. Anat., 2010. © 2009 Wiley‐Liss, Inc.     

The relationship of the posterior inferior cerebellar artery to cranial nerves VII-XII

The posterior inferior cerebellar artery (PICA) is the largest branch of the vertebral artery. It usually arises at the anterolateral margin of the medulla oblongata close to the lower cranial nerves. The PICA had the most complex relationship to the cranial nerves of any artery and it is frequently exposed in approaches directed to the fourth ventricle. The aim of this article is to describe the anatomical relationship of the PICA to the lower cranial nerves. In this study, 12.5% of PICAs passed between the glossopharyngeal and vagus nerves, 20% between the vagus and accessory nerves, and 65% through the rootlets of the accessory nerve. The lateral medullary segment of the PICA showed a lateral loop which in 20% specimens pressed against the inferior surfaces of the facial and vestibulocochlear nerves. The lateral medullary segment of the PICA in 20% specimens passed superior to the hypoglossal nerve, in 47.5% through the rootlets of the hypoglossal nerve, and in 30% inferior to the hypoglossal nerve. The findings on the relationship of the PICA to the lower cranial nerves could be helpful in microsurgery of this region.     

Systematization,description, and territory of arteries that promote vascularization of the midbrain and rhombencephalon in the ostrich (Struthio camelus)

Brain specimens from 30 ostriches were injected with red-dyed latex via the internal carotid arteries (Aa.). The ventral tectal mesencephalic artery (a.), invariably a medium-sized single vessel, was, on the right side, a collateral branch of the caudal branch of the carotid artery (53.4%), a direct branch of the carotid artery (43.3%) and a direct branch of the basilar artery (3.3%) and on the left side, a collateral branch of the caudal branch of the carotid artery (66.7%), a direct branch of the carotid artery (30%), and a direct branch of the basilar artery (3.3%). It vascularized only the ventral half of the optic lobe, with no involvement in cerebellar vascularization on the right (93.3%) and left (80%) sides, extending to the ventrorostral-most cerebellar lobules, which were vascularized on the right (6.7%) and left (20%) sides. The caudal ventral cerebellar arteries were a single vessel on the right (96.7%) and left (93.3%) sides. Its first branch was a common trunk: dorsal spinal—caudal cerebellar on the right (60%) and left (56.6%) sides. Its second branch was the caudal cerebellar artery on the right (76.7%) and left (86.7%) sides. Its third branch was the second component of the caudal cerebellar artery on the right (6.7%) and left (3.3%) sides. The midbrain was vascularized by dorsal and ventral tectal mesencephalic arteries. The cerebellum was vascularized by branches of the caudal ventral cerebellar artery and by the dorsal cerebellar artery.     

Rare case of right accessory renal artery originating as a common trunk with the inferior mesenteric artery: a case report

Dissection of a male cadaver revealed several vascular abnormalities in the abdominal cavity, notably of the renal circulation. In particular, three renal arteries were observed on the right side and two on the left. On the right side, one accessory renal artery originated as a common trunk with the inferior mesenteric artery. Additional variations included a left inferior phrenic artery originating from the celiac trunk, bilateral testicular veins emptying into renal veins, and the left testicular artery arising from the left renal artery. The possible embryonic development of these branching patterns and their clinical significance are discussed briefly.     

The right inferior phrenic artery: path of its ascending branch at the vena caval foramen

The ascending branch of the right inferior phrenic artery is generally understood to pass to the lateral side of the vena caval foramen, on the inferior surface of the diaphragm. A study of 16 cadavers shows that the artery may pass through the vena caval foramen to run on the superior surface of the diaphragm, before returning to the inferior surface by passing through the muscle of the diaphragm.     

The posterior inferior cerebellar artery and its branches in relation to the cerebellomedullary fissure

The conventional approach to the fourth ventricle is by splitting the vermis on the suboccipital surface of the cerebellum. By a unilateral transcerebellomedullary fissure approach, it is possible to provide sufficient operative space from cerebral aqueduct to obex without splitting the vermis. This approach needs meticulous dissection of the cerebellomedullary fissure and preservation of the posterior inferior cerebellar artery (PICA) and its branches. The tonsillomedullary and telovelotonsillar segments of the PICA are the most important vessels encountered in the transcerebellomedullary fissure approach. The PICA was examined under a surgical microscope in a total of 40 specimens by perfusing with a mixture of 10% Indian ink and gelatin. The passing of the tonsillomedullary segment of the PICA through the cerebellomedullary fissure was observed superior to the tonsil in 5%, at the level of the upper pole of the tonsil in 17.5%, at the middle of the tonsil in 37.5% and at the level of the lower pole of the tonsil in 37.5% specimens. When the PICA arose from the lateral medullary (LM) segment of the vertebral artery (VA), a caudal loop was present in 90%, when the PICA originated from the premedullary segment of the VA, the loop was present in 87.5% specimens. When the PICA arose from the basilar artery (BA), the loop was absent, and the tonsillomedullary segment of the PICA showed a straight course (100%). A thorough understanding of the relationship of the branches of the PICA to the cerebellar tonsils are prerequisites for surgery in and around the fourth ventricle.     

人小脑上动脉的应用解剖学研究

目的研究小脑上动脉毗邻关系及分支分布,为颅后窝小脑、脑干病变手术提供形态学依据。方法选13个人颅脑标本,在眉弓与枕外隆凸连线行水平锯开,暴露小脑上动脉并进行显微解剖观测。结果小脑上动脉在小脑幕内下与滑车神经伴行并与之交叉后行于其上方,行程中分支到小脑上面的多为3～4支,第一支分布于本侧半球上面的前外侧部、第二支分布于中间部、第三支分布于内侧部、第四支分布于蚓部。其分支分布到中脑和脑桥背面的多为2-3支,第一、二支分布于中脑背外侧面,第三支分布于中脑和脑桥连接处的背面。结论小脑上动脉在小脑幕内下行于滑车神经上方,在影像学上是确定滑车神经的理想标志,其每侧主要分支不仅供应本侧小脑半球上面,而且发分支供应中脑和脑桥的背外侧面。     

Ascending vermian artery, branch of the V4 segment of the vertebral artery

A previously undescribed anatomical variant is reported here, that of vermian arteries (vAs) branched from the vertebral arteries (VAs) and replacing the medial branches of the posterior inferior cerebellar arteries (PICAs) that, in turn, were leaving the basilar artery. Both vAs left the VAs in the foramen magnum. The left vA initially looped in front of the spinal root of the accessory nerve (Sp11) and then looped inferiorly on the dorsal side of the spinal cord, in the vertebral canal and continued ascending on the dorsal surface of the medulla oblongata. The right vA looped dorsally to the Sp11 above the foramen magnum, and also ascended dorsally to the medulla. Both vAs were distributed to the vermis. On both sides, the PICAs looped above the glossopharyngeal nerves and the jugular foramina and continued as only lateral terminal branches of a normal PICA that descended in countercurrent on the outer side of the variant vAs. Such anatomical variation is relevant for surgery and microsurgery on both sides of the foramen magnum and in the posterior cerebral fossa.     

Arterial variations of the upper extremities

During the dissection of the right and left upper limbs of a 70-year-old female cadaver, we encountered combined vascular anomalies. On the left side, we observed the presence of a lateral inferior superficial brachial artery, large anterior interosseous artery and an absence of a radial artery, which is quite a rare anomaly. The lateral inferior superficial brachial artery that arose 39 mm distal to the brachial artery descended to the wrist. The anterior interosseous artery originated from the brachial artery at the level of 12 mm distal to the head of the radius and descended on the anterior aspect of the interosseous membrane with the anterior interosseous branch of the median nerve. On the right side, a trifurcation of the brachial artery was observed. It gave off three terminal branches: the radial, ulnar and a muscular artery at the proximal one-third of the humerus. It is obvious that accurate information concerning unusual patterns of the arteries in the upper limbs is relevant clinically, especially in order to avoid accidental injury or intra-arterial injection.     

The presence of a foramen of Luschka in the American alligator (Alligator mississippiensis) and the continuity of the intraventricular and subdural spaces

In humans and most mammals, there is a notch-like portal, the foramen of Luschka (or lateral foramen), which connects the lumen of the fourth ventricle with the subdural space. Gross dissection, light and scanning electron microscopy, and μCT analysis revealed the presence of a foramen of Luschka in the American alligator (Alligator mississippiensis). In this species, the foramen of Luschka is a notch in the dorsolateral wall of the pons immediately caudal to the peduncular base of the cerebellum, near the rostral end of the telovelar membrane over the fourth ventricle. At the foramen of Luschka there was a transition from a superficial pia mater lining to a deep ependymal lining. There was continuity between the lumen of the fourth ventricle and the subdural space, via the foramen of Luschka. This anatomical continuity was further demonstrated by injecting Evans blue into the lateral ventricle which led to extravasation through the foramen of Luschka and pooling of the dye on the lateral surface of the brain. Simultaneous subdural and intraventricular recordings of cerebrospinal fluid (CSF) pressures revealed a stable agreement between the two pressures at rest. Perturbation of the system allowed for static and dynamic differences to develop, which could indicate varying flow patterns of CSF through the foramen of Luschka.