男性盆腔内脏神经的解剖学研究及其临床意义

男性盆腔内脏神经与盆筋膜及盆内脏器的毗邻关系复杂,且个体形态学差异大,临床上涉及肛肠外科、泌尿外科、男科等多个学科,应用甚广。近年来,对内脏神经的术中保护越来越受到重视。男性盆腔内脏神经主要包括上腹下丛、腹下神经、下腹下丛(即盆丛)、盆内脏神经、膀胱丛、前列腺丛、直肠丛及其分支等。现已证明盆腔内脏神经的损伤会给患者的排便、排尿及阴茎勃起等造成功能障碍。熟悉男性盆腔内脏神经及其分支的形态特点及其与周围结构的关系,能降低手术并发症,提高患者术后生活质量。     

全直肠系膜切除相关盆自主神经的解剖学观察

目的：阐述全直肠系膜切除术相关盆自主神经的局部解剖学特点，探讨盆自主神经保留的部位和对策。方法：对20具男性盆腔固定标本进行解剖观察。结果：腹主动脉丛远离肠系膜下动脉起点；上腹下丛贴近骶岬表面；腹下神经部分毗邻输尿管；盆内脏神经伴行直肠中动脉外侧部；下腹下丛位于直肠系膜后外侧；其直肠侧支走行于直肠侧韧带内，直肠前支向前穿过Denonvilliers筋膜后叶；勃起神经位于Denonvilliers筋膜前叶外侧部。结论：盆自主神经保留的部位是：离断肠系膜下血管时的腹主动脉丛左干，直肠后分离时的上腹下丛和腹下神经，直肠侧面分离时的下腹下丛和盆内脏神经，直肠前分离时的勃起神经。共同原则是：在直肠后间隙中贴近直肠系膜操作；直视下操作；避免过度牵引直肠系膜。     

人海绵体神经的应用解剖及临床意义

海绵体神经起源于盆神经丛的次级神经丛-前列腺丛,含有交感神经纤维和副交感神经纤维两种成分。该神经与尿道血管形成神经血管束,沿前列腺两侧向远端走形,穿尿生殖膈后,发出分支进入海绵体,或与阴茎背神经交通,最后管理阴茎勃起组织。在盆内手术如膀胱、前列腺的根治性手术和全直肠系膜切除术后因海绵体神经损伤而导致患者术后勃起功能障碍时有发生。熟悉海绵体神经及其分支的走行特点及其与周围结构的关系,能降低手术并发症。在海绵体神经损伤后的重建方面也取得了一定的成果。     

盆部内脏神经血管的解剖特点及临床应用

目的:探讨经腹腔镜行全直肠系膜切除术中盆部内脏神经和血管的保护.方法:解剖32具成人躯干标本(女15、男17)和31侧成人男性骨盆矢状标本,结合腹腔镜手术,观测有关的盆腔血管神经的形态及定位.结果:(1)骶中静脉大多1支,61%偏左,骶外侧静脉53%为两支,骶前静脉丛在骶曲处密集粗大,骶椎椎前穿通静脉在第4、5骶椎前方形成静脉窦,且与骨膜结合紧密.(2)盆从位于距直肠外侧约1.1cm和距直肠膀胱陷凹上外测约4.7cm处的骨盆侧壁.左右腹下神经分别于骶骨岬上下1.0～2.0 cm的范围内分出,其夹角约95.9°.上腹下丛位于腹主动脉分叉周围至骶骨岬下2 cm之间.(3)腹腔镜下骶前间隙主要由少量的疏松结缔组织填允容易分离,解剖层面清晰.结论:手术中应找准解剖层面,根据血管神经的定位以神经为导向进行分离,可避免损伤盆部的内脏神经及骶前静脉丛.     

男性盆丛神经的观察及其临床意义

目的：直肠癌扩大根治术是提高术后生存率，减少癌细胞转移的重要术式，但其术后排尿和性功能障碍并发症较多，其原因是术中损伤了盆丛神经。本文对盆丛的研究可为改进直肠癌扩大根治术，降低并发症，提高生存质量，提供解剖学资料。方法：用３０侧男性盆腔标本，通过冰醋酸松解剥离方法，对盆丛的起源、组成和分支分布进行了详细观测。结果：盆丛长径为４１．６±７．３ｍｍ，宽径２９．８±８．５ｍｍ。盆丛又继续形成直肠丛、膀胱丛和前列腺丛，三个次级丛参与管理排尿功能和性功能。结论：手术中如能对盆丛及其次级丛神经加以保护，免受或减少损伤，可防止或减少术后并发症的发生。     

轴向腰椎椎间融合术入路的应用解剖

目的　探讨经骶前间隙轴向腰椎椎间融合术入路的安全性。 方法　(1) 12具（24侧）防腐固定成人骨盆段标本,解剖骶前间隙,观察骶前的筋膜层次,骶直肠筋膜,盆内脏神经等,测量骶直肠筋膜和盆内脏神经的相关解剖数据。(2) 参照Marotta方法,模拟手术置入导针,测量导针在骶前间隙中的相关解剖学数据。 结果　(1)骶前的筋膜可分为5层;(2)骶直肠筋膜的出现率是91.7%,在骶前壁层筋膜的起始部位：S2为16.7%,S3为41.7%,S4为33.3%,它将骶前间隙分为上、下两部分; (3)盆内脏神经限制直肠下段的解剖分离,可作为骶前间隙“矢状安全区域”的指标,其长度是（22.9±3.2）mm; (4)模拟手术时,导针到盆内脏神经的最短距离是（7.8±1.9）mm,到S3/4横线的垂直距离是（15.0±3.6）mm。 结论　经骶前间隙轴向腰椎椎间融合术入路的安全性是相对的,由于骶直肠筋膜、骶前静脉丛横干和骶前血管变异的存在,手术入路面临着较大的风险。     

宫颈癌根治术后神经源性排尿障碍的解剖学因素及预防

在24侧成人女性标本上,解剖观察了盆腔脏器旁结构的内容、分层及脏器旁结构中盆丛的组成、位置、分支和分布,并对盆丛作了分区定位.观察了子宫骶韧带和子宫主韧带与盆丛的相互关系.分析探讨了宫颈癌根治术后神经源性排尿障碍的原因及术中保护部分盆丛的临床应用要点.     

男性盆腔神经丛的外科应用解剖

目的　探讨泌尿外科术中避免损伤盆腔神经丛 (盆丛 )的解剖标志。方法　对 42具盆腔器官作盆腔解剖或组织切片 ,观察盆丛与盆腔脏器的毗邻关系。结果　盆丛位于直肠的前外侧 ,距肛门口 ( 9.5± 1.6)cm ,精囊的后外侧 ,在前列腺基底部与前列腺血管形成神经血管束 ,于尿道膜部外侧和后外侧 ,穿尿生殖膈。结论　精囊和前列腺神经血管束可作为泌尿外科术中防止损伤盆丛的一个标志。     

Mile′s术怎样保护盆内脏神经的解剖学研究

Mile’s术通常引起排尿障碍和性机能障碍等术后并发症,其部分原因是手术损伤了盆内脏神经。在40侧成人尸体上观察测量了盆内脏神经的来源、支数、长度、横径,并对该神经作了定位调查,为手术保护提供了依据。     

用低温冰冻材料制作内脏神经丛标本

<正> 交感神经、副交感神经和内脏感觉神经在分布于脏器的过程中,相互交织在一起,共同构成内脏神经丛,由于这些神经纤维较细小,且纵横交错,与结缔组织胶合在一起,难以分离,给标本制作造成了一定的困难.为了尽可能完整的制作出内脏神经丛标本,我们利用低温冰冻材料制作内脏神经丛标本,获得了较满意的效果.方法如下.1 选材和取材选用经福尔马林防腐固定的小童尸体,也可利用学生解剖过且腹后壁较完好的尸体材料.先将上、下肢离断,再从腹中线将各肋骨剪断,切开腹外侧壁,将胸、腹壁一起去掉,再从肺门切除左、右肺叶.切除肝、脾、胃、大小肠等腹腔脏器,然后把材料冲洗干净.2 低温冷冻将上述材料放进低温冰箱里冰冻3天(0℃以下)然后把材料拿出冲水解冻1天,再将材料放进冰箱冷冻.如此反复3～4次,便可进行标本制作.3 标本制作经过冰冻的材料,其组织结构之间变得疏松,神经纤维和结缔组织之间出现了“间隙”.这样在标本的制作过程中就显得容易轻松了许多,也能最大限度的保留神经丛的完整性.按常规的解剖方法就能把心丛、肺丛、腹腔丛、腹主动脉丛和腹下丛等完全显示出来.     

Nerve contributions to the pelvic plexus and the umbilical cord

Serial sections of human embryos and fetuses reveal that the sacral nerves which contribute fibers to the pelvic plexus often have dorsal, ventral, and oblique communicating rami. The ventral rami resemble the white rami of upper thoracic nerves and some of their fibers pass close by or through the chain ganglia and into the pelvic plexus. The sizes of the ventral rami are often in inverse proportion to that of the pelvic splanchnic nerves. That is, when the pelvic splanchnic nerves are poorly developed, the ventral rami are large, and conversely, when the pelvic splanchnic nevers are well developed, these rami are small. The pelvic plexus was found to receive fibers from the sympathetic trunk and its ganglia in addition to those from the hypogastric plexus and the pelvic splanchnic nerves. Analysis of the observations made in this study together with a review of the literature in light of the present day classification of nerve fibers raises serious doubts concerning the limits set for the outflow of preganglionic nerve fibers from the spinal cord and the distribution of gray and white rami as described in recent textbooks in terms of their histological and physiological significance. Nerve fibers from the pelvic plexus can be traced along the walls of the bladder and the urachus and along the umbilical arteries into the umbilical cord. In embryos, only a few scattered nerve fibers were found distal to the umbilicus, but in fetuses at term, distinct nerve bundles were identified in the cord. These bundles sent branches to the walls of the umbilical arteries; other branches terminated as “end-nets” in Wharton's jelly. These nets appeared as fine fibers with nodular swellings at irregular intervals. Innervation of the umbilical arteries was richest within the first few inches of the cord. Beyond this region, the nerves rapidly decreased in number. “End-nets” were present as far as four inches from the umbilicus. Granular cells resembling Langerhans' cells were found in the cord. Often these cells were closely associated with fine nerve fibers.     

An anatomical investigation on the muscles of the pelvic outlet in crab-eating monkey (Macaca irus) and Japanese monkey (Macaca fuscata) with special reference to their nerve supply

For a fuller understanding of the nerve supply to the muscles of the pelvic outlet in man, 4 pelvic-halves of crab-eating monkeys and 6 pelvic-halves of Japanese monkeys were minutely dissected. 1) The composition of the pudendal plexus tends to be limited to 2 segments, S1 and S2. 2) If we consider the origin of the nerves, the pudendal plexus is divided into 2, the first or medial and the second or lateral parts. From the first part arise the pelvic splanchnic nerves, the nerve to the iliopubocaudalis and the nerve to the ischiocaudalis. From the second part the dorsal nerve of the penis or clitoris, the perineal nerve and the inferior rectal nerve originate. 3) A laminate arrangement exists among the 3 nerves from the first part at their origin; the pelvic splanchnic nerves are situated ventrally, and the nerve to the ischiocaudalis dorsally, with the nerve to the iliopubocaudalis in between. No obvious laminate arrangement exists among the 3 nerves from the second part. 4) The part of the iliopubocaudalis, contiguous with the rectal wall but without attaching to it, has no branches of supply from the perineal nerve and the inferior rectal nerve. 5) A detailed discussion of our findings in relation to man, is given below.     

The innervation of the external urethral sphincter muscle

Innervation of external urethral sphincter muscle was examined in 100 human fetuses and 10 adults of both sexes. Examined nerves take place from deep perineal nerve (branch of pudendal nerve) and, probably, from pelvic splanchnic nerves (via inferior hypogastric plexus). However, this supposition needs further microscopic research. It is also concluded that pelvic splanchnic nerves and pudendal nerve arise from the same ventral branches of spinal nerves (S2-S4).     

A review of the thoracic splanchnic nerves and celiac ganglia

Anatomical variation of the thoracic splanchnic nerves is as diverse as any structure in the body. Thoracic splanchnic nerves are derived from medial branches of the lower seven thoracic sympathetic ganglia, with the greater splanchnic nerve comprising the more cranial contributions, the lesser the middle branches, and the least splanchnic nerve usually T11 and/or T12. Much of the early anatomical research of the thoracic splanchnic nerves revolved around elucidating the nerve root level contributing to each of these nerves. The celiac plexus is a major interchange for autonomic fibers, receiving many of the thoracic splanchnic nerve fibers as they course toward the organs of the abdomen. The location of the celiac ganglia are usually described in relation to surrounding structures, and also show variation in size and general morphology. Clinically, the thoracic splanchnic nerves and celiac ganglia play a major role in pain management for upper abdominal disorders, particularly chronic pancreatitis and pancreatic cancer. Splanchnicectomy has been a treatment option since Mallet‐Guy became a major proponent of the procedure in the 1940s. Splanchnic nerve dissection and thermocoagulation are two common derivatives of splanchnicectomy that are commonly used today. Celiac plexus block is also a treatment option to compliment splanchnicectomy in pain management. Endoscopic ultrasonography (EUS)‐guided celiac injection and percutaneous methods of celiac plexus block have been heavily studied and are two important methods used today. For both splanchnicectomies and celiac plexus block, the innovation of ultrasonographic imaging technology has improved efficacy and accuracy of these procedures and continues to make pain management for these diseases more successful. Clin. Anat. 23:512–522, 2010. © 2010 Wiley‐Liss, Inc.     

Topography of the pelvic autonomic nervous system and its potential impact on surgical intervention in the pelvis

Bladder, bowel, and sexual dysfunction caused by iatrogenic lesions of the inferior hypogastric plexus (IHP) are well known and commonly tolerated in pelvic surgery. Because the pelvic autonomic nerves are difficult to define and dissect in surgery, and their importance often ignored, we conducted a gross anatomic study of 90 adult and four fetal hemipelves. Using various non-surgical approaches, the anatomic relations and pathways of the IHP were dissected. The IHP extended from the sacrum to the genital organs at the level of the lower sacral vertebrae. It originated from three different sources: the hypogastric nerve, the sacral splanchnic nerves from the sacral sympathetic trunk (mostly the S2 ganglion), and the pelvic splanchnic nerves, which branched primarily from the third and fourth sacral ventral rami. These fibers converge to form a uniform nerve plate medial to the vascular layer and deep to the peritoneum. The posterior portion of the IHP supplied the rectum and the anterior portion of the urogenital organs; nerve fibers traveled directly from the IHP to the anterolateral wall of the rectum and to the inferolateral and posterolateral aspects of the urogenital organs. The autonomic supply from the IHP was supplemented by nerves accompanying the ureter and the arteries. An understanding of the location of the autonomic pelvic network, including important landmarks, should help prevent iatrogenic injury through the adoption of surgical techniques that reduce or prevent postoperative autonomic dysfunction.     

Extrinsic innervation of the pelvic organs in the lesser pelvis of human embryos

Realistic models to understand the developmental appearance of the pelvic nervous system in mammals are scarce. We visualized the development of the inferior hypogastric plexus and its preganglionic connections in human embryos at 4–8 weeks post-fertilization, using Amira 3D reconstruction and Cinema 4D-remodelling software. We defined the embryonic lesser pelvis as the pelvic area caudal to both umbilical arteries and containing the hindgut. Neural crest cells (NCCs) appeared dorsolateral to the median sacral artery near vertebra S1 at ~5 weeks and had extended to vertebra S5 1 day later. Once para-arterial, NCCs either formed sympathetic ganglia or continued to migrate ventrally to the pre-arterial region, where they formed large bilateral inferior hypogastric ganglionic cell clusters (IHGCs). Unlike more cranial pre-aortic plexuses, both IHGCs did not merge because the 'pelvic pouch', a temporary caudal extension of the peritoneal cavity, interposed. Although NCCs in the sacral area started to migrate later, they reached their pre-arterial position simultaneously with the NCCs in the thoracolumbar regions. Accordingly, the superior hypogastric nerve, a caudal extension of the lumbar splanchnic nerves along the superior rectal artery, contacted the IHGCs only 1 day later than the lumbar splanchnic nerves contacted the inferior mesenteric ganglion. The superior hypogastric nerve subsequently splits to become the superior hypogastric plexus. The IHGCs had two additional sources of preganglionic innervation, of which the pelvic splanchnic nerves arrived at ~6.5 weeks and the sacral splanchnic nerves only at ~8 weeks. After all preganglionic connections had formed, separate parts of the inferior hypogastric plexus formed at the bladder neck and distal hindgut.     

Origin of peptide-containing fibers in the inferior mesenteric ganglion of the guinea-pig: Immunohistochemical studies with antisera to substance P,enkephalin, vasoactive intestinal polypeptide,cholecystokinin and bombesin

After different denervation procedures the guinea-pig inferior mesenteric ganglion was analysed by immunohistochemistry using antisera to substance P, enkephalin, vasoactive intestinal polypeptide, cholecystokinin and bombesin. The results demonstrate that each of the nerve trunks connected to the ganglion carries specific peptidergic pathways. Thus, the lumbar splachnic nerves contain substance P-immunoreactive primary afferent neurons, which to a large extent traverse the ganglion, and enkephalin-immunoreactive preganglionic neurons; the colonie nerves carry vasoactive intestinal polypeptide-, cholecystokinin- and bombesin-immunoreactive fibers from the distal colon to the ganglion; the hypogastric nerves contain vasoactive intestinal polypeptide-positive fibers from the pelvic plexus; and the intermesenteric nerve contains vasoactive intestinal polypeptide, cholecystokinin, substance P and enkephalin from divergent sources. By studying accumulations of peptides in ligated lumbar splanchnic, intermesenteric, hypogastric and colonic nerves the existence of these major peptidergic pathways was confirmed and evidence was obtained for additional, not so prominent, peptidergic projections. The results are discussed in view of earlier morphological and physiological studies.     

The hypogastric nerve innervates a population of penile neurons in the pelvic plexus

Retrograde dye staining, enkephalin immunocytochemistry and nerve lesion paradigms were used to determine if penile neurons in the pelvic plexus are innervated by fibers in the hypogastric nerve. In the intact major pelvic ganglion of the rat, some 80% of penile neurons are enclosed by an enkephalin-positive fiber plexus. Following surgical interruption of the pelvic nerve, 20% of penile neurons were still surrounded by an enkephalin plexus. After interruption of the pelvic nerve and the hypogastric nerve, the enkephalin plexus in the ganglion was virtually absent, including the plexus around penile neurons. Therefore, possible intrinsic sources of the enkephalin fibers such as enkephalin-positive principal neurons and small intensely fluorescent cells, do not account for the delicate enkephalin fiber system in the pelvic ganglion. It is concluded that the pelvic nerve is the major source of preganglionic innervation to penile neurons in the major pelvic ganglion. However, it is significant that the hypogastric nerve is preganglionic to about 20% of penile neurons. The pathway through the hypogastric nerve may represent an alternate vasodilator system to penile erectile tissue.