The function of the celiac plexus is to receive both parasympathetic and sympathetic inputs from the vagus (CN X) and splanchnic nerves, and to convey their respective postsynaptic outputs to the abdominal viscera. This article will discuss the anatomy and function of the solar plexus.
|Definition||Autonomic plexus consisting of paraaortic ganglia on the anterior surface of abdominal aorta|
|Location||Around the roots of celiac trunk, superior mesenteric artery and renal artery|
|Function||Sympathetic, parasympathetic and nociceptive innervation to the distal esophagus, stomach, pancreas, spleen, kidneys, liver and gallbladder via periarterial nervous plexuses|
|Clinical relations||Celiac plexus block|
The celiac plexus consists of celiac, superior mesenteric, and renal ganglia found surrounding the roots of the celiac trunk, superior mesenteric, and renal arteries. For their paraaortic location, these ganglia are also called prevertebral (paraaortic) ganglia. Ganglia are interconnected into smaller celiac, superior mesenteric and renal plexuses, which together comprise one large celiac (solar) plexus.
The celiac plexus outsources parasympathetic, sympathetic and nociceptive fibers. Parasympathetic input for the celiac plexus comes from the vagus nerve (CN X), while the sympathetic input is from the greater and lesser splanchnic nerves. Branches of the celiac plexus reach their target organs by forming periarterial plexuses surrounding the branches of the abdominal aorta. Thus, the celiac plexus supplies the inferior part of the esophagus, stomach, pancreas, spleen, kidneys, liver, gallbladder, and small intestine.
The function of the celiac plexus is to transmit visceral sensory impulses (like pain or reflexes) from the foregut and midgut. It increases gland secretion and promotes peristalsis and digestion with its parasympathetic division. The sympathetic division inhibits peristalsis, constricts blood vessels and redirects blood to skeletal muscles.
Celiac plexus block
People with chronic pancreatitis or malignancies in the upper abdominal region often suffer from unmanageable abdominal pain due to constant stimulation of celiac plexus nociceptive fibers. In these cases, celiac plexus block is a therapeutic procedure which helps with decreasing the pain sensation. A celiac plexus block is performed by inserting a thin needle through one’s posterior abdominal wall. The physician is guided by an X-ray, and once they reach the celiac plexus, they inject the painkiller. This procedure can relieve pain from several weeks up to several years.