Anatomy of thoracic splanchnic nerves for surgical resection

Thoracic splanchnic nerves conduct pain sensation from the abdominal organs around the celiac ganglion. Splanchnicectomy is the procedure used mainly for the control of intractable visceral pain. Forty-six human posterior thoracic walls were dissected. The formation pattern, course, and incidence of communication of the thoracic splanchnic nerves were investigated. The greater splanchnic nerves (GSNs) were formed by nerve branches from the T4-T11 thoracic sympathetic ganglia and the most common type was formed by T5-T9 (21.7%). The uppermost branches originated from T4-T9 while the lowermost branches emanated from the T7-T11. Two to seven ganglia contributed to the GSNs. In 54.3% of the specimens, at least one ganglion in the GSN-tributary ganglionic array did not branch to the GSN. The lesser splanchnic nerves (LSNs) were formed by the nerve branches of the T8-T12 thoracic sympathetic ganglia and the most common type was formed by T10 and T11 (32.6%). One to five ganglia were involved in the LSNs. The least splanchnic nerves (lSNs) were composed of branches from the T10-L1 thoracic sympathetic ganglia and the most common type was composed of nerve branches from T11 and T12 or from T12 only (each 30.4%). One to three ganglia were involved in the lSNs. In 54.3% of the specimens, interconnection between the GSNs and the LSNs existed, bringing the possible bypass around the transection of the GSNs. The splanchnic nerves that appear in textbooks occurred in a minority of our specimens. We provided expanded anatomical data for splanchnicectomy in this report.     

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.     

Nerve pathways in celiac plexus of the guinea pig.

In vitro preparations consisted of the right and left celiac, superior mesenteric and inferior mesenteric ganglia with attached extrinsic nerves, vasculature, mesentery, and colon. There were no systematic differences in membrane electrical properties (recorded intracellularly) between neurons in the different ganglia. Stimulation of associated nerve trunks produced graded synaptic responses in plexus neurons. Presynaptic fibers were found in splanchnic and mesenteric nerves. Input from celiac nerves dominated in the celiac galglia; input from the intermesenteric fibers dominated in the superior mesenteric ganglion. When the ganglia were attached to the entire colon, 33% of the neurons in the celiac and 54% in the superior mesenteric ganglion received a continuous excitatory synaptic input that was increased by distending the colon. This input was interrupted irreversibly by transsection of the mesenteric nerves. These results show that both the afferent and efferent pathways of a peripheral reflex arc are located in the mesenteric nerves and may mediate visceral reflexes between mechanoreceptors and sympathetic neurons in the colon.     

Constitution of the greater splanchnic nerve in the rat

The greater splanchnic nerve originating from the sympathetic ganglia between the 10th and 12th ribs on the dorsal thoracic wall passes through the diaphragm between its medial and lateral erura, to form the celiac plexus around the celiac trunk and superior mesenteric artery in the abdominal cavity. The nerve consists of about 10,000 of nerve fibers and of 25,000 of ganglion cells in its whole length of 2.5 cm; nerve fibers can be divided into myelinated fibers, accounting for less than 6% of total numbers, and unmyelinated fibers, which amount to more 90%. Special attention was not paid to the numerous ganglion cells in terms of their shapes, sizes, and cell organelles except for a small number of binucleate cells. However, the nerve contains remarkable synapses that connect between axon showing flat, elliptical, and cored vesicles and dendrite, between another type of axon having elliptical and cored vesicles and dendrite, and even between dendrite and cell body, in which synaptic vesicles are small spherical and elliptical. These facts can suggest that the greater splanchnic nerve contains more complex structure than has been hitherto described.     

Distribution and origin of peptide-containing nerve fibers in the celiac superior mesenteric ganglion of the guinea-pig

The origin of the peptidergic nerve fibers and terminals in the celiac superior mesenteric ganglion of the guinea-pig was studied. The distribution of immunoreactivity to enkephalin, substance P, calcitonin gene-related peptide, cholecystokinin, vasoactive intestinal polypeptide/peptide histidine isoleucine, bombesin and dynorphin was analysed in intact animals and in animals subjected to various denervation and ligation procedures. The present results show that each of the connected nerve trunks carries peptidergic pathways and contributes to the peptidergic networks in the celiac superior mesenteric ganglion. Thus, the thoracic splanchnic nerves contain enkephalin-, substance P- and calcitonin gene-related peptide-immunoreactivity of which substance P and calcitonin gene-related peptide coexist in the same nerve fibers. In addition, cholecystokinin-, vasoactive intestinal polypeptide/peptide histidine isoleucine- and dynorphin-immunoreactivity is present in some fibers. All of these immunoreactivities are present in sensory neurons except enkephalin which probably originates in the spinal cord. The mesenteric nerves carry enkephalin-, calcitonin gene-related peptide-, cholecystokinin-, vasoactive intestinal polypeptide/peptide histidine isoleucine-, bombesin- and dynorphin-immunoreactive fibers from the intestine and are the main source for cholecystokinin, vasoactive intestinal polypeptide/peptide histidine isoleucine, bombesin and dynorphin fibers. Double-staining experiments indicate that many of these peptides are synthesized in the same enteric neurons. Also the intermesenteric nerve contains peptide-immunoreactive fibers to the celiac superior mesenteric ganglion from different sources, probably including the distal colon as well as dorsal root ganglia and spinal cord at lower thoracic and lumbar levels. The results are discussed in relation to earlier morphological and physiological studies supporting the view of a role of the celiac superior mesenteric ganglion in local reflex mechanisms involved in regulation of gastrointestinal functions.     

Thoracic splanchnic nerves: implications for splanchnic denervation

Splanchnic neurectomy is of value in the management of chronic abdominal pain. It is postulated that the inconsistent results of splanchnicectomies may be due to anatomical variations in the pattern of splanchnic nerves. The advent of minimally invasive and video-assisted surgery has rekindled interest in the frequency of variations of the splanchnic nerves. The aims of this study were to investigate the incidence, origin and pattern of the splanchnic nerves in order to establish a predictable pattern of splanchnic neural anatomy that may be of surgical relevance. Six adult and 14 fetal cadavers were dissected (n = 38). The origin of the splanchnic nerve was bilaterally asymmetrical in all cases. The greater splanchnic nerve (GSN) was always present, whereas the lesser splanchnic nerve (LSN) and least splanchnic nerve (lSN) were inconsistent (LSN, 35 of 38 sides (92%); LSN, 21 of 38 sides (55%). The splanchnic nerves were observed most frequently over the following ranges: GSN, T6–9: 28 of 38 sides (73%); LSN, when present, T10–11: (10 of 35 sides (29%); and lSN, T11–12: 3 of 21 sides (14%). The number of ganglionic roots of the GSN varied between 3 and 10 (widest T4–11; narrowest, T5–7). Intermediate splanchnic ganglia, when present, were observed only on the GSN main trunk with an incidence of 6 of 10 sides (60%) in the adult and 11 of 28 sides (39%) in the fetus. The higher incidence of the origin of GSN above T5 has clinical implications, given the widely discussed technique of undertaking splanchnicectomy from the T5 ganglion distally. This approach overlooks important nerve contributions and thereby may compromise clinical outcome. In the light of these variations, a reappraisal of current surgical techniques used in thoracoscopic splanchnicectomy is warranted.     

胆囊传入神经的节段性分布——CT-HRP法研究

将CT—HRP注入胆囊壁游离面,取脊神经节、迷走神经结状节作TMB法反应。结果是(1)胸2—13和腰1节段的脊神经节内有大量的标记细胞,右侧者数量占优势,左右胸7—10节标记细胞数量为高峰节段。(2)仅在右颈5—7脊神经节中发现不同数量的标记细胞,出现率约占实验动物的1/3,切断右侧膈神经后在颈部脊髓神经节中不出现标记细胞。(3)双侧迷走神经结状节中均发现标记细胞,左右侧在数量上无明显差异。脊神经节或结状节的标记细胞均以中小型为主,也有少最大型细胞。     

The pattern of the thoracic splanchnic nerves as they pass through the diaphragm

The formation and structure of the greater, lesser, and least thoracic splanchnic nerves is highly variable in their intrathoracic as well as their subdiaphragmatic portion. Splanchnicectomies for pain control of otherwise intractable upper abdominal pain and other surgical procedures are dependent on the detailed knowledge of the anatomy of these nerves and their variations. Many commonly used anatomical illustrations depict the passage of the thoracic splanchnic nerves through the diaphragm uniformly as three nerves penetrating the crura in three separate locations along a rough superoinferior line. As this pattern does not correspond with our own sporadic observations, we performed a series of dissections to study the exact anatomy of this area. Dissections of 24 donors revealed that the most common pattern of diaphragmatic passage of these three nerves is through a single location in each crus. From this crural passageway, the three nerves then diverge to reach their targets, with the greater thoracic splanchnic nerve bending anteriorly at nearly 90° to enter the posterolateral edge of the celiac ganglion. Modern anatomical illustrations should depict these most common patterns of the subdiaphragmatic portion of the thoracic splanchnic nerves and mention the great variability of their formation and structure. Clin. Anat. 22:809–814, 2009. © 2009 Wiley‐Liss, Inc.     

The Contribution of the Left Phrenic Nerve to Innervation of the Esophagogastric Junction

The contribution of the left phrenic nerve to innervation of the esophagogastric junction. The esophagogastric junction is part of the barrier preventing gastroesophageal reflux. We have investigated the contribution of the phrenic nerves to innervation of the esophagogastric junction in humans and piglets by dissecting 30 embalmed human specimens and 14 piglets. Samples were microdissected and nerves were stained and examined by light and electron microscopy. In 76.6% of the human specimens, the left phrenic nerve participated in the innervation of the esophagogastric junction by forming a neural network together with the celiac plexus (46.6%) or by sending off a distinct phrenic branch, which joined the anterior vagal trunk (20%). Distinct left phrenic branches were always accompanied by small branches of the left inferior phrenic artery. In 10% there were indirect connections with a distinct phrenic nerve branch joining the celiac ganglion, from which celiac plexus branches to the esophagogastric junction emerged. Morphological examination of phrenic branches revealed strong similarities to autonomic celiac plexus branches. There was no contribution of the left phrenic nerve or accompanying arteries from the caudal phrenic artery in any of the piglets. The right phrenic nerve made no contribution in any of the human or piglet samples. We conclude that the left phrenic nerve in humans contributes to the innervation of the esophagogastric junction by providing ancillary autonomic nerve fibers. Experimental studies of the innervation in pigs should consider that neither of the phrenic nerves was found to contribute. Clin. Anat. 33:265–274, 2020. © 2019 Wiley Periodicals, Inc.     

Facial nerve parasympathetic preganglionic afferents to the accessory otic ganglia by way of the chorda tympani nerve in the cat

 The distribution of accessory otic ganglia and connections between the ganglia and the chorda tympani nerve were investigated in the cat in order to determine the parasympathetic preganglionic facial nerve afferents to the otic ganglia using whole mount acetylthiocholinesterase (WATChE) histochemistry. The otic ganglia consist of a sigle main prominent ganglion and many small accessory ganglia lying on a plexus around the origins of the branches of the mandibular nerve and near the junction of the chorda tympani nerve and lingual nerve. In cell analysis of Nissl-stained preparations, the neurons composing the accessory otic ganglia were morphologically similar to the main otic ganglion neurons. Connecting branches from the chorda tympani nerve to the peripherally located acccessory otic ganglia were found and they were not stained by WATChE histochemistry. WATChE-positive connecting branches from the ganglia to the inferior alveolar, lingual, and mylohyoid nerves were also found in the same preparations. The WATChE histochemistry on various autonomic nervous tissues revealed that autonomic postganglionic nerve fibers are selectively stained darkly and that preganglionic fibers remain unstained. Therefore, it is considered that the WATChE-negative connections from the chordra tympani nerve consist chiefly of autonomic preganglionic fibers, whereas the WATChE-positive connections to the branches of the mandibular nerve are mainly postganglionic fibers. This suggests that some of the facial nerve parasympathetic preganglionic fibers in the chorda tympani nerve are mediated in the accessory otic ganglia and then join the branches of the mandibular nerve to supply the target mandibular tissues. Accepted: 25 November 1997     

Branches of the thoracic sympathetic trunk in the human fetus

Summary The segmental organization of the thoracic sympathetic trunk and all its ramifications was studied in 6 human fetuses (16–22 weeks) by means of the acetylcholinesterase in toto staining method. Each trunk was divided into 12 sympathetic segments. A segment is defined as that part of the sympathetic trunk which is connected via its rami communicates with one spinal nerve, without discriminating between grey and white rami. The diameter of the rami communicantes and their direction towards the spinal nerves are variable. The number of peripheral segmental ramifications of the trunk is much larger than assumed previously. Each thoracic sympathetic segment gives off at least 4–5 nerves. Three categories of nerves are discerned: (1) large splanchnic rootlets confined to the greater, lesser and least thoracic splanchnic nerves, (2) medium-sized splanchnic nerves directed towards thoracic viscera, some of which give off branches towards costovertebral joint plexuses and, described for the first time in man, (3) small nerves which ramify extensively and form nerve plexuses in the capsule of the costovertebral joints. The majority of the ramifications is formed by the nerves of the third category. The existence of Kuntz's nerve, connecting the 2nd intercostal nerve and 1st thoracic spinal nerve, is confirmed in four specimens. The nerve plexuses of the costovertebral joints receive a segmentally organized innervation: they receive their input from the neighbouring sympathetic segment and the one cranial to it.It is concluded that the thoracic sympathetic branches in man show a complex, segmentally organized pattern and may have a considerable component of somatosensory nerve fibers. The complex relationships must be taken into account in surgical sympathectomies.     

Distribution of myelinated nerves in ascending nerves and myenteric plexus of cat colon

The parts of the colon differ in motor function and in responses to extrinsic and intrinsic nerve stimulation. The distribution of myelinated nerve fibers in the colonic myenteric plexus is not known. Because these fibers might be largely extrinsic in origin, their distribution might indicate the domain of influence of extrinsic nerves and help to explain the different behaviors of the different parts of the colon. Myelinated fibers were examined by electron microscopy in cross sections of the ascending nerves and in myelin-stained whole-mount preparations in the colon. The ascending nerves are much like one another. They have the structure of peripheral nerves, not that of myenteric plexus. The proportion of myelinated fibers in the ascending nerves declines rostrad with no uniform change in total nerve fiber number. Cross-sectional areas of ascending nerves, 3,304 to 7,448 μm²; total number of nerve fibers per profile, 703–2,651; and mean myelin coat thickness, 0.45 ± 0.01 μm, do not change uniformly along the ascending nerves. Myelinated fibers are about 2% of total fibers in the extramural colonic nerves, 7–9% in the ascending nerves in the sigmoid colon, and 2–3% at the rostrad ends of the ascending nerves in the transverse colon. Blood vessels lie at the core of each ascending nerve and on the nerve sheath. Myelinated fibers in the ascending nerves degenerate after section of colonic branches of the pelvic plexus and after section of the pudendal nerves, indicating that myelinated nerves reach the colon through both pathways. Myelinated fibers extend into the myenteric plexus through short lateral branches from the ascending nerves to adjacent ganglia where they turn to run cephalad throughout most of the colon but caudad in the rectum. Myelinated fibers do not extend into the cecum or proximal ascending colon. The nonuniform distribution of myelinated fibers along the colon, many of which are extrinsic in origin, could in part explain the disturbances in defecation that sometimes follow limited distal colonic resection, gynecologic surgery, and obstetric damage to the pudendal nerves in man.     

An anomalous case of the thoracic cardiac nerve in the Japanese monkey

A rare case of an anomalous right thoracic cardiac nerve that directly distributed to the left ventricle and left coronary artery was observed in a Japanese monkey. Its nerve arose from 4th and 5th thoracic ganglia on the right sympathetic trunk, descended obliquely along the thoracic vertebra toward the thoracic aorta at the level of the body of 7th thoracic vertebra. After reaching the aorta, it reflected upward and ascended along the medial-ventral surface of the aorta. Thereafter, it received a cardiac branch arising from the vagus nerve in the upper part of the thoracic aorta, and ran to the left-lateral aspect of the heart. Finally, it gave off main branches to the terminal part of the left coronary artery and the left ventricle, and small branches to the proximal part of the left coronary artery. In a human dissection, similar nerves (the thoracic splanchnic nerve or thoracic pulmonary nerve) originating at the thoracic ganglia and reaching to the lung, have also been observed. The superior, middle and inferior cervical cardiac nerves can easily reach the heart along the common carotid artery, the brachiocephalic artery and subclavian artery. But it is not easy for the thoracic cardiac nerve to reach the heart because of the topographical relationship of its thoracic origin and the peripheral distributions of the left side of the heart. Therefore, the thoracic cardiac nerve would have to run a complicated course.     

盆腔内筋膜的解剖结构及神经走形：避免修复中的损伤

背景：盆腔内走行着大量支配泌尿生殖等系统脏器的神经,包括内脏神经和脊神经两种,每一种均由运动神经和感觉神经两种成分组成。其中内脏神经的核心为盆丛。1982年,Heald提出的全直肠系膜切除已经成为直肠癌诊疗的“金标准”。但术中极易损伤神经,导致术后出现尿潴留、性功能障碍等并发症。目的：综述前人的研究,以明确盆腔内筋膜的解剖结构和神经走形。方法：以“splanchnic nerves,superior hypogastric plexus,pelvic plexus,pelvic splanchnic nerve,total mesorectal excision(TME),clinical anatomy”为关键词,检索2000年1月至2015年1月PubMed数据库中关于盆腔内神经及相关脊神经的走形和成分、盆腔内神经节及相关脏器反射等研究,以盆腔内的神经为主。结果与结论：盆腔内的主要内脏神经丛为：①上腹下丛：主体位于由左、右髂总动脉和骶岬围成的髂间三角内,左髂总静脉和第5腰椎前面。②盆丛：腹下神经、盆内脏神经、骶内脏神经在直肠侧面的后下方1/3处汇合形成神经丛,也称下腹下丛,位于输尿管后下方、膀胱及精囊腺的背侧。由内脏神经丛发出的神经包含交感神经、副交感神经及感觉神经3种成分,走行分布在盆腔各脏器表面,支配其运动与感觉功能。明确的盆腔内筋膜的解剖结构和神经走形是全直肠系膜切除成功的关键,可在手术中最大程度避免神经损伤,提高患者预后及生活质量。中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

Can intestinal innervation be preserved in pancreatoduodenectomy for cancer? Results of an anatomical study

Twenty dissections were carried out, in all of which the splanchnic nerves, celiac plexuses, capital pancreatic plexus and superior mesenteric plexus were identified and traced. The capital pancreatic plexus was formed from two bundles, the first taking its origin from the right celiac plexus, the second from the superior mesenteric plexus. These two bundles joined together just behind the head of the pancreas. Two preganglionic bundles, a ganglion and two postganglionic bundles composed the superior mesenteric plexus. Postganglionic bundles received fibers from both right and left celiac plexuses. In small cancers a thin layer of nervous tissue around the superior mesenteric artery might be spared in order to avoid diarrhea from intestinal denervation. This study has provided anatomical evidence that a part of the mesenteric plexus, which receives fibers from both left and right celiac plexuses, maintains a sufficient intestinal innervation.     

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).     

Contribution of the cervical sympathetic ganglia to the innervation of the pharyngeal arch arteries and the heart in the chick embryo

In the chick heart, sympathetic innervation is derived from the sympathetic neural crest (trunk neural crest arising from somite level 10–20). Since the trunk neural crest gives rise to sympathetic ganglia of their corresponding level, it suggests that the sympathetic neural crest develops into cervical ganglia 4–14. We therefore tested the hypothesis that, in addition to the first thoracic ganglia, the cervical ganglia might contribute to cardiac innervation as well. Putative sympathetic nerve connections between the cervical ganglia and the heart were demonstrated using the differentiation markers tyrosine hydroxylase and HNK‐1. In addition, heterospecific transplantation (quail to chick) of the cardiac and trunk neural crest was used to study the relation between the sympathetic neural crest and the cervical ganglia. Quail cells were visualized using the quail nuclear antibody QCPN. The results by immunohistochemical study show that the superior and the middle cervical ganglia and possibly the carotid paraganglia contribute to the carotid nerve. This nerve subsequently joins the nodose ganglion of the vagal nerve via which it contributes to nerve fibers in cardiac vagal branches entering the arterial and venous pole of the heart. In addition, the carotid nerve contributes to nerve fibers connected to putative baro‐ and chemoreceptors in and near the wall of pharyngeal arch arteries suggesting a role of the superior and middle cervical ganglia and the paraganglia of the carotid plexus in sensory afferent innervation. The lower cervical ganglia 13 and 14 contribute predominantly to nerve branches entering the venous pole via the anterior cardinal veins. We did not observe a thoracic contribution. Heterospecific transplantation shows that the cervical ganglia 4–14 as well as the carotid paraganglia are derived from the sympathetic neural crest. The cardiac neural crest does not contribute to the neurons of the cervical ganglia. We conclude that the cervical ganglia contribute to cardiac innervation which explains the contribution of the sympathetic neural crest to the innervation of the chick heart. Anat Rec 255:407–419, 1999. © 1999 Wiley‐Liss, Inc.     

The functional morphology of the afferent systems of the splanchnic nerves

Summary The morphology, the sources of formation and the functional characteristics of the afferent sympathetic fibers of the splanchnic nerves were studied.The removal of the gall bladder and of the small intestine, as well as of the semilunar ganglia of the solar plexus was associated with a secondary degeneration of the amyelinated and thin myelinated conductors contained in the splanchnic nerves. This fact shows that they pertain to the neurites of the receptor neurons (II type Dogiel's cells) located in the plexuses within the walls of the corresponding organs.The electrophysiological and the histochemical study of these neurites was studied after the exclusion of all the spinal afferent fibers of the splanchnic nerves. The preservation of their morphology, function and the enzymatic activity in the peripheral portion of the splanchnic nerve in 21–27 days after its section was demonstrated. Their physiological characteristics are determined by the functional, state of the corresponding organ.Presented by Active Member AMN SSSR V.N. ChernigovskiiA paper presented to the First Belorussian Conference of Anatomists, Histologists, Embryologists and Topographical Anatomists on June 14, 1957, in Minsk.