A review of the thoracic splanchnic nerves and celiac ganglia

Abstract

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.

Sympathetic Blockade

“…It travels medially across the vertebral body, passes through the crus of the diaphragm, and terminates at the celiac plexus. Interestingly, this nerve was found to be absent in 43% of dissections, bilaterally [ 20,22 ] . Individually, each of these nerves contains preganglionic visceral sympathetic • efferent neurons from the thoracic sympathetic chain plus postganglionic visceral afferent neurons that provide pain sensation from the upper abdominal organs to the central nervous system [ 21,22 ] .…”

“…The • lesser splanchnic nerve is formed by the rami of the ninth through 11th thoracic sympathetic ganglia. After exiting the ganglia, it travels inferomedial to the vertebral bodies at this level, passes through the crus of the diaphragm, and terminates at the celiac plexus [ 20,22 ] . The • least splanchnic nerve is the most caudal, originating from the 12th thoracic sympathetic ganglion.…”

“…It originates from the four roots of the thoracic sympathetic ganglia, descends obliquely, pierces the crus of the diaphragm at a 90˚ angle, and joins to the celiac plexus [20][21][22] . The • lesser splanchnic nerve is formed by the rami of the ninth through 11th thoracic sympathetic ganglia.…”

“…This large network of nerves, including a right and left ganglia, is a region where • pre-and postganglionic neurons from the sympathetic, parasympathetic, and visceral sensory divisions synapse [ 21,22 ] . This large star-or oval-shaped plexus is 0.5-4.5 cm in diameter and spans a • region from the 12th thoracic vertebra disc space to the middle vertebral body of the second lumbar vertebra [ 22 ] .…”

Management of Pain in Autosomal Dominant Polycystic Kidney Disease and Anatomy of Renal Innervation

“…Fibers from the superior portion of the intermesenteric plexus also run directly to the renal plexus. 7,[10][11][12] The greater splanchnic nerve may connect to the renal plexus through the aorticorenal or celiac ganglia, which was seen in a minority of cadavers. Small connections to the renal plexus from the inferior portion of the intermesenteric plexus and superior portion of the hypogastric plexus were also found in some cadavers.…”