 For cancer operations, recently, in addition to lymphatics, function preservation has become a focal point. To achieve function preservation, precise knowledge of the autonomic nerves, blood vessels, and lymphatics is necessary. In this video, actual anatomical dissection of three significant plexuses within the thorax, abdomen, and pelvis will be demonstrated. The sympathetic components from the right and left sympathetic trunks descend and converge to form three plexuses. Interestingly, each loop-like formation is actually lower than its origination. The parasympathetic components are divided into those from the cranial part and the sacral part. The cranial components descend from the right and left vagal nerves, whereas the sacral components originate from the pelvic splintnik nerves and run horizontally. In part one, we will show the cardiac plexus which is distributed to the lung in addition to the heart. As the sympathetic and vagal components descend along the major vessels and also along the trachea and esophagus, this complex formation must be well understood for function preservation techniques. In a male specimen, we will look at the cardiac region. With the lungs removed and the inferior vena cava cut, the heart is reflected upwards and the pericardium is cut to view the esophagus. The right bronchus is reflected leftward. Here, we see the left brachiosophallic vein, the superior vena cava, and the azygous vein. Here, in the right cervical thoraxic transitional area, the vagus descends and gives off the right recurrent laryngeal nerve and cardiac branches. Then, intermingled with sympathetic cardiac branches, the mixed branches descend along the trachea to reach the root of the lung. With the ascending aorta reflected leftward, we will examine the anterior surface of the right pulmonary artery. Note that while the medial branches continue as cardiac branches, the lateral branches run along the right pulmonary artery to enter the right lung. We will cut the major vessels to show the autonomic nerves more clearly. Now, we can see the superior cervical ganglion and the superior and inferior thyroid arteries. By reflecting the brachiosophallic trunk upwards, you can see the right recurrent laryngeal nerve and the vagus. Here is the right cervical sympathetic trunk and the inferior cervical ganglion and slightly lower is esthetic ganglion. From this trunk and these ganglia, numerous branches originate and enter the vagus nerve. All twigs are first given off to the trachea. There is a three-dimensional space behind the superior vena cava, bordered by the right side of the trachea, the aortic arch and the right pulmonary artery. In this space, the sympathetic and vagal branches converge. While most branches go between the aortic arch and the pulmonary artery to enter the deep cervical plexus, one branch goes over the aorta to the superficial cardiac plexus. The left lung is reflected to the right. We see the common carotid artery and left subclavian arteries and left vagus. Two bronchial arteries are seen. Behind the lung root is the legamentum arteriosum and also we see the winding left recurrent laryngeal nerve. By reflecting the aortic arch leftward, we see the left recurrent laryngeal nerve ascending between the trachea and esophagus. It gives off numerous segmental branches to both the trachea and esophagus. This recurrent nerve ascends behind the thyroid gland to reach the larynx. Shifting the left half of the trachea to the right, we can see the intimate relationships of the left peritracheal lymphatic chain and the recurrent nerve tracheoesophageal branches. Now we cut the left subclavian artery and shift the aortic arch downwards to obtain a clear view of the area behind the aortic arch where the sympathetic and vagal elements converge. Tracing the left side sympathetic nerves, we note these branches join the left recurrent laryngeal nerve. With the aortic arch return to its original position, we see the left vagal trunk give off branches to form the pulmonary plexus behind the root of the lung. From the pulmonary plexus, the left vagus descends along the esophagus and shifts to the anterior side before reaching the diaphragm. Now we will look at the heart and the cardiac plexus. By shifting the ascending aorta, we can see that the right sympathetic nerves and vagal branches have converged. These branches then descend to the left coronary artery along the ascending aorta and surround it. As most of the autonomic branches descend behind the ascending aorta, here we will cut the ascending aorta for a better view. Likewise, we will cut the pulmonary trunk, freeing the heart except for only its supplying nerves. With the aortic arch shifted, looking at the right pulmonary artery, you can see an autonomic nerve loop. Now we will cut the right pulmonary artery, freeing this nerve loop. You can see the bifurcation of the trachea directly beneath the pulmonary artery. The autonomic nerves form a network at the base of the ascending aorta. The left coronary plexus surrounds the left coronary artery and its major branches. Autonomic nerve branches from this coronary plexus follow the coronary artery branches and are distributed. Due to time limitations, we will not show it here, but the right coronary plexus similarly surrounds the right coronary artery and branches. With the heart freed, now we will look at the right side. The right vagal trunk descends behind the right lung root. We see the right bronchial artery, which originates from a right posterior intercostal artery. After removal of this artery, we can clearly see the right vagal trunk descend along the esophagus. It gives off thick branches to the right lung. This is the formation of the right pulmonary plexus. The composition, course, and distribution of the autonomic nerves in the thorax have been shown. The celiac plexus is the most important autonomic nerve plexus in the abdomen. This plexus is formed at the level of L1, where three major arteries are situated. The splenchnic nerves descend to unite with the posterior vagal trunk, forming the celiac plexus. With the heart and the left lung removed, we will follow the vagal element along the esophagus. The anterior vagal trunk, which is mainly formed by the left vagus, descends along the esophagus. In the formation of the posterior vagal trunk, the left vagus joins the right vagus. To follow the vagus to the abdomen, the diaphragm is cut and opened, and the left lobe of the liver is removed. Just before the esophago-gastric junction, the anterior vagal trunk bifurcates into the hepatic branch and the gastric branch. Here we see an accessory left gastric artery and the typical left gastric artery. The left gastric artery arises from the celiac trunk, while the accessory left gastric artery arises from the hepatic artery. Near this accessory artery, we see the hepatic branch of the vagus. In addition to the cartial branch, we see the anterior gastric branch, which runs along the lesser curvature, anterior to the left gastric artery, and reaches the angular incisor. It is important to note that the anterior vagal trunk is distributed to the liver and stomach. In contrast, the posterior vagal trunk, in addition to distribution to the stomach, contributes to the formation of the celiac plexus. Thus, it is the posterior vagal trunk, together with the sympathetic nerves, which form this important plexus. Let us look at the formation of the left celiac ganglion. With the stomach reflected to the right, close to the left suprarinogland, we see the left celiac ganglion. Here is the greater splanchnic nerve. And passing behind the esophagus is the posterior vagal trunk. We see that the posterior gastric branch, after giving off the cardiac branches, runs along the lesser curvature and reaches the angular incisor. The main part of the posterior vagus descends to reach the left celiac ganglion. Thus, together the greater splanchnic nerve and the posterior vagus form the celiac ganglion. With the pancreas and spleen reflected, we trace the nerves from the left celiac ganglion along the splanchnic artery. Some branches are distributed to the left suprarinogland and kidney. Note the thick branches surrounding the superior mesentery artery. With the stomach returned to its original position, in addition to the hepatic branch, we see a transverse branch around the cardiac notch. Let us trace it to identify it. After again reflecting the stomach and the pancreas, we locate the left celiac ganglion and the left inferior phrenic artery. Interestingly, while this artery is distributed to the diaphragm, its corresponding nerve crosses the lower end of the esophagus and is distributed to the liver. In order to view the right celiac ganglion, the right lung and diaphragm are reflected. The right cruise of the diaphragm is cut. Looking at the continuation of the thoraxic and abdominal portions, we see the course of the sympathetic trunk. In a close-up view of the greater splanchnic nerve, we trace it and find the lesser splanchnic nerve as well as the lowest splanchnic nerve. By replacing the kidney and pulling the greater splanchnic nerve, we can see the moving area and locate the right celiac ganglion. This ganglion is within the upper corner of the inferior vena cava and the left renal vein. Now we'll look at the vagal component of this right celiac ganglion. By pulling the posterior vagal trunk behind the esophagus, its contribution to the formation of the celiac ganglion is recognized. The hepatic vein is cut to disconnect the liver. For a better view, the inferior vena cava and left renal vein are cut and reflected. The right cruise of the diaphragm is also cut. Now both contributions, the posterior vagus trunk and the left nerve can be seen. This right celiac ganglion is critically located behind the pancreas head near the celiac and right renal arteries. In the second specimen, the duodenum and pancreas have been reflected. With the liver reflected, the hepatic pedicle is seen from behind. Here is the right celiac ganglion. Its branches ascend behind the portal vein to reach the liver and gallbladder. This is the posterior surface of the pancreas head. By opening the duodenum, we see the duodenal pepillow. Numerous pancreas nerves are noted and a lymph node is seen. Here is the posterior pancreatical duodenal arterial arcade. The nerves run superficial to the arcade. The right side of the superior mesenteric artery is also covered by thick nerves. These nerves originated from the right celiac plexus. We have observed the autonomic nerve distribution to the upper abdominal organs. In the third specimen, we will look at the autonomic nerve distribution to the intestines. From the superior mesenteric plexus, numerous nerves are intertwined with the supplying arteries of the small intestine. Pulling the small intestine to the left, we note the ileocecal region, which is supplied by the ileocolic artery and its accompanying nerves. The ascending and transverse colon is supplied by the superior mesenteric artery. Likewise, the nerve supply originates from the superior mesenteric plexus. In this specimen, an accessory middle colic artery complete with nerve supply was found. By pulling the small intestine upwards and to the right, we see the descending and sigmoic colon and the abdominal aorta. Note the inferior mesenteric artery and the nerves which form the inferior mesenteric plexus. Close to the sigmoic colon, we see different fiber groups which do not accompany the blood vessels. Following these fibers, we find they originate from the pelvic plexus. From this pelvic plexus, if we trace these ascending parasympathetic branches, we see they cross the inferior mesenteric plexus branches and reach the descending colon. As shown in this demonstration, the descending and sigmoic colon receives sympathetic supply via the inferior mesenteric plexus and also parasympathetic supply from the pelvic plexus. The pelvic plexus is important as it supplies most pelvic organs. Here in a male specimen, we will demonstrate this plexus in addition to other critical nerves. The right perineal region is viewed after removal of the hip bones and shifting of the testis. Looking first at the sacro plexus, we note the sciatic nerve from this plexus. Nearby is the internal pudendal artery and the pudendal nerve. We will look at the muscular innervation of the perineal nerve. By reflecting the bulbospondiosis and the ischiocavenosis, we can see the bulb of the penis. These two muscles, which surround the radix of the penis, have important roles for urogenital function. Between these two muscles is the inferior fascia of the urogenital diaphragm. We see the nerve to the ischiocavenosis muscle and those to the urogenital diaphragm. Numerous thin nerves from the perineal nerve supply the bulbospondiosis. It is important to note that these pudendal nerve branches originate from S2 to S4, which is the same level as the origin of the parasympathetic pelvic splanchnic nerve. Reflecting the levator ante, we see the rich venous plexus beneath it. Also between the bladder and prostate lie large veins. These make up the vesicle prostatic venous plexus. Now we'll remove the veins to facilitate a clear review of the arteries and nerves. However, we will keep this vein intact between the prostate and rectum as important nerves to the penis lie beneath it. Passing in front of the prostate, this vein connects to that lower internal pudendal vein, as well as to the dorsal vein of the penis. In the dissection of the arteries, first we see the medial vesicle ligament and the superior vesicle arteries. Supplying the anus, perineum, and dorsum of the penis is the internal pudendal artery. Here is the inferior vesicle artery. It pierces the pelvic plexus and supplies the lower bladder and the prostate. Slightly below the inferior vesicle artery is the middle rectal artery, which reaches the border between the rectum and prostate. We cut the superior vesicle arteries of the nerves. The pelvic plexus is composed of sympathetic nerves and parasympathetic nerves. There are two sympathetic components. The major one is via para-vascular hypo-gastric nerves and the other one is sacral splanctinic nerves via the sympathetic chain. Near the inferior vena cava and ureter, we see the major sympathetic component, the nervous plexus around the aorta. The lumbar splanctinic nerve originates from the lumbar sympathetic trunk. The left and right lumbar splanctinic nerves unite slightly below the inferior mesenteric artery to form the superior hypo-gastric plexus. They again divide into right and left hypo-gastric nerves and descend within the pelvis. With the testis and ductus deferens reflected leftwards, we see the right hypo-gastric nerve. It sends a direct branch to the ureter. With the ureter shifted, we can clearly see the hypo-gastric nerve and also the parasympathetic pelvic splanctinic nerves. In order to view the minor sacral splanctinic nerves, we cut the inferior vesicle artery. Now we can see the minor sympathetic component. The sympathetic sacral splanctinic nerve does not enter the pelvic plexus directly. Rather, it first joins the parasympathetic pelvic splanctinic nerves. Several thin pelvic splanctinic nerves from S3 and also S4 are seen. The urogenital branches of the pelvic plexus can be roughly divided into four groups, upper, middle, lower and lower most. In the upper group, we can see loop formation around the ureter and the distribution to the bladder. The middle group runs to the bladder neck and the upper prostate. The lower group is distributed to the prostate. And the lower most group runs between the prostate and rectum to reach the anterior end of the levator ante, with some fibers entering the levator ante. Note the important space bordered by the pubic symphysis, prostate and levator ante. Nerves pass through this space to reach the dorsum of the penis as a cavernous nerves, which are visceral. Here we see rectal branches. The nerve to the levator ante actually is not a pelvic plexus branch, but it originates from the same level as the pudental nerve and pelvic planktonic nerves. Again, we see the hypogastric nerve and the pelvic planktonic nerves. Note the spaces above and below the pelvic planktonic nerves. Now we will median section the penis in order to view the medial branches of the pelvic plexus. From the external urethral orifice, we carry out a slightly rightward median section. We insert a probe from the internal urethral orifice into the prostatic urethra. We can see the rectum and peritoneal reflection and also numerous rectal branches. This is the ampulla of the ductus deferens and the right seminal vesicle. Here is the terminal portion of the right seminal vesicle. Behind the seminal vesicle is the rectal vesicle septum, which is continuous from the peritoneal reflection. Returning to the pelvic plexus, we can see the hypogastric nerves' contribution, the pelvic planktonic nerves are hidden behind the ureter. Looking at the rich nerve supply, we see the branches to the ampulla of the ductus deferens and that to the seminal vesicle. These branches supply the prostate. Near the peritoneal reflection, there are numerous branches to the rectum and also lower branches which go to the rectum as well. We see the artery between the prostate and rectum, which we had left intact. Here we see the rectum behind the prostate. And also from inside we see the same artery and realize that it not only supplies the rectum, but also the prostate. The nerves which supply the rectum lie posterior to the rectal vesicle septum. Interestingly, rectal nerves also ascend along the superior rectal artery to reach the sigmoid colon. We have demonstrated the composition and distribution of the pelvic plexus.