As each head reached the end of the table , a worker would insert a metal hose into the foramen magnum , the opening that the spinal cord passes through 当猪头到达操作台的末端的时候，工人会将一根金属管子插入到枕大孔(脊髓穿过的地方)内。
Acute cerebral swelling can also often produce herniation of the cerebelllar tonsils into the foramen magnum . note the cone shape of the tonsils around the medulla in this cerebellum 急性大脑肿胀在枕骨大孔处也经常形成小脑扁桃体疝，注意小脑髓质附近的锥体形状的小脑扁桃体。
A wide anastomosis connecting transversely the intercostals arteries can be observed on the thoracic segments , which located on the intervertebral foramen and musculus sacrospinalis nearby , while anastomosis on lumbar segments on iliopsoas muscle and psoas major . 3 胸段毗邻的肋间动脉吻合主要是椎间孔周围和骶棘肌内两处；而腰段还有椎体侧面的骼腰肌和腰大肌中的吻合。
Measurements for the following anatomical structures were obtained with the aid of a microscope , the distance between mastoid process and transverse process of the atlas , occipital condyle , and superior lateral loop ; the distances between the midline and the v3 at three levels : 1 ) the distal ( dural ) ring ; 2 ) the intersection with the anterior ramus of the c - 2 ; and 3 ) the upper level of the transverse foramen of the atlas ; the diameter of v3h at the origin of the muscular artery and at the sites of penetrating the dural ring ; the width of the v3 at the intersection with the anterior ramus of the c - 2 and at the sites of penetrating the transverse foramen of the atlas V _ 3h和v _ 3v各有两个分支： v _ 3h分出肌动脉支和脑膜后动脉支； v _ 3v分出肌动脉支和根肌动脉支，第一、二脊神经发出的前后支分别与它们又毗邻关系。通过手术显微镜测量下述解剖结构：乳突尖与环椎横突尖、枕髁外侧缘、 v _ 3上外侧袢的距离；椎动脉v _ 3段在穿硬膜环、与第二颈神经前支交叉、环椎横突孔上缘三处与中线的距离； v _ 3h在发出肌支处和穿硬膜天浑医科大学硕士研究主学位论文环处的直径； v3v在与第二颈神经前支交叉处和穿环椎横突孔处的直径。
We studied the microsurgical anatomy of this region concentrating on the third segment ( v3 ) of the va , from which extends the transverse foramen of the axis to the dural penetration by the va , we paid particular attention to the loops , branches , supporting fibrous rings , and surrounding venous structures of the va , as well as the relationship between their anatomical elements and their surrounding structures 本文研究枕下区域的显微解剖，主要集中在椎动脉的第三段( thethirdsegmentofvertebralartery ， v _ 3 ) ，其范围从枢椎横突孔到椎动脉穿入硬膜处，并侧重研究了v _ 3的血管袢、分支、纤维环和周围的静脉结构，以及它们与周围结构的解剖关系。
Conclusion ( 1 ) depending on location ， size and invading extension of the tumor ， above different approaches are adapted selectively which can provide excellent exposure and allow for an aggressive resection of the tumor . ( 2 ) the tumor tissue of the cavenous sinus and foramen lacerum is resected carefully by microsurgery . ( 3 ) the dural deficiecy must be repaired and sutured tightly to avoid craniocerebral fluid leak 结论（ 1 ）前或和中颅凹底内外沟通性肿瘤应根据肿瘤大小、位置及侵犯范围选择颅面联合入路、额颞-颞下窝入路或额颞-颞下窝入路结合面前径路即可给于充分暴露并能在直视下广泛切除肿瘤； （ 2 ）中颅凹底侵及海绵窦和破裂孔部的肿瘤应在较高放大倍数手术显微镜下仔细分离切除； （ 3 ）硬膜的严密修复是避免脑脊液漏及颅内感染的重要关键。
