The celiac region refers to the anatomical zone surrounding the celiac trunk, a short but critical artery that branches off the front of the abdominal aorta just below the diaphragm, typically at the level of the twelfth thoracic vertebra. This region also encompasses the celiac plexus, a dense web of autonomic nerves that relays pain and organ-control signals for much of the upper abdomen. Together, the artery and nerve plexus make the celiac region central to digestion, pain perception, surgical planning, and several uncommon but serious medical conditions.
Where the Celiac Trunk Sits and What It Feeds
The celiac trunk is the first major branch the aorta sends forward once it passes through the diaphragm into the abdomen. In a cadaveric study, the trunk emerged between the twelfth thoracic vertebral body and the first lumbar vertebral body in about 90% of cases, with the full range extending from the tenth thoracic vertebra down to the first lumbar vertebra.1PubMed Central. The Celiac Trunk and Its Anatomical Variations: A Cadaveric Study It is remarkably short, usually just one to two centimeters long, before it divides into three branches: the left gastric artery (feeding the stomach), the splenic artery (feeding the spleen and part of the pancreas), and the common hepatic artery (feeding the liver, gallbladder, and duodenum).2PubMed. Variations in the anatomy of the celiac trunk: A systematic review and clinical implications That classic three-way fork is sometimes called the “tripod of Haller,” after the eighteenth-century anatomist who described it.
This tidy textbook picture, though, applies to only a portion of the population. One imaging study of over 600 patients found the classic branching pattern in roughly 64% of cases, with about 36% showing some variation, the most common being the right hepatic artery arising instead from the superior mesenteric artery.3PubMed Central. Anatomical variation of celiac axis, superior mesenteric artery, and hepatic artery: Evaluation with multidetector computed tomography angiography A larger study of over a thousand patients put the classic trifurcation rate even lower, at about 39%, with the most common alternative being a combined celiac-phrenic trunk where the artery also gives off one of the inferior phrenic arteries.4Polish Journal of Radiology. Newly proposed classification of celiac artery variations based on embryology and correlation with computed tomography angiography The disagreement in exact percentages between studies reflects differences in what counts as a “variant” and the populations studied, but the practical takeaway is the same: surgeons should never assume textbook anatomy when operating in this area.
How These Variations Develop
The celiac trunk forms during early embryonic life from a network of small paired arteries called vitelline arteries that supply the developing gut tube. Three of these persist as the adult’s major digestive arteries: the celiac artery feeds structures derived from the foregut, the superior mesenteric artery feeds the midgut, and the inferior mesenteric artery feeds the hindgut.5Edorium Journal of Anatomy and Embryology. Embryology, comparative anatomy, and congenital malformations of the gastrointestinal tract – Section: Vasculature Initially, these arteries are connected by a longitudinal channel running along the front of the aorta. The adult configuration depends on which segments of that channel disappear and which roots of the vitelline arteries persist. When those regressions happen differently than usual, you get the various branching anomalies described above, including rare forms like a combined celiac-mesenteric trunk where the celiac and superior mesenteric arteries share a single origin.6Journal of Vascular Surgery / Jornal Vascular Brasileiro. Unusual development of the celiac trunk and its clinical significance
The Celiac Plexus and Pain Transmission
Wrapped around the root of the celiac trunk, in the fatty tissue behind the stomach, lies the celiac plexus. This is one of the body’s largest collections of autonomic nerve tissue outside the brain and spinal cord. It acts as a relay station for pain signals traveling from the upper abdominal organs, from the stomach all the way to the proximal part of the transverse colon.7PubMed. CT-guided celiac plexus neurolysis: a review of anatomy, indications, technique, and tips for successful treatment The plexus receives input from the thoracic splanchnic nerves, which carry sympathetic fibers from the spinal cord, and it also receives some vagal (parasympathetic) input. Confocal microscopy studies in animals have confirmed vagal nerve endings in the celiac ganglia and in the smaller nerve clusters associated with the surrounding arterial plexuses, suggesting the vagus nerve plays a role in modulating the sympathetic signals passing through.8Journal of the Autonomic Nervous System. Characterization of vagal innervation to the rat celiac, suprarenal and mesenteric ganglia
This dual identity as both an arterial hub and a nerve hub is what makes the celiac region so important in clinical medicine. A condition that compresses the artery can also irritate the nerves, and a procedure aimed at treating pain can affect blood flow if not carefully targeted.
Blood Flow During Digestion
One of the celiac trunk’s main jobs is delivering blood to the stomach, liver, and spleen, and the demand changes dramatically when you eat. In human studies, blood velocity in the celiac artery started climbing within a minute of beginning a meal and peaked at roughly 60% above baseline within about five minutes.9PubMed. Blood flow responses in celiac and superior mesenteric arteries in the initial phase of digestion That early spike reflects the stomach gearing up to process what just arrived. By contrast, the superior mesenteric artery, which feeds the small and large intestine, took much longer to peak, reaching its maximum increase of over 130% about 40 minutes into digestion, when chyme had moved downstream into the intestine.
Animal studies have shed light on how this happens. In conscious dogs, celiac blood flow shot up to nearly double its resting level within two minutes of eating but then dropped back to baseline relatively quickly, even though most of the food was still in the stomach. This response was blocked by cutting the vagus nerve or by anesthetizing the stomach lining, but not by drugs that block the classic “fight-or-flight” or “rest-and-digest” chemical signals. The researchers concluded that the celiac surge is driven by a specialized vagal reflex that is neither conventionally adrenergic nor cholinergic.10PubMed. Postprandial celiac and superior mesenteric blood flows in conscious dogs Further work in rats confirmed that celiac blood flow is regulated primarily through sympathetic nerve input, while the mesenteric vessels rely more on a stretch-based mechanism in the vessel walls themselves.11PubMed. Different flow regulation mechanisms between celiac and mesenteric vascular beds in conscious rats In other words, the two major digestive arteries use fundamentally different control systems, which has implications for how disease or nerve damage in the celiac region can disrupt digestion.
Built-In Backup Circulation
The celiac trunk and the superior mesenteric artery are connected by several natural bridges, the most important being the pancreaticoduodenal arcades, looping arteries that run through the pancreas and duodenum. A less common bridge called the arc of Bühler, a direct embryonic remnant, is occasionally present as well.12PubMed. Clinical interest of digestive arterial trunk anastomoses These connections explain a fact that often surprises people learning about vascular disease: even significant narrowing or complete blockage of the celiac artery rarely causes the kind of bowel death you might expect from losing a major artery. When the celiac trunk narrows, blood can flow backward through the pancreaticoduodenal arcades and the dorsal pancreatic artery from the superior mesenteric artery to keep the liver, stomach, and spleen supplied.13PubMed. Collateral pathways in patients with celiac axis stenosis: angiographic-spiral CT correlation
This redundancy is a lifesaver, but it also means that celiac artery stenosis can smolder quietly for years. Symptoms of upper abdominal ischemia are vague enough, including postprandial pain and weight loss, that the underlying cause is often found only when someone is specifically looking for it on imaging.14PubMed. The celiac axis revisited: anatomic variants, pathologic features, and implications for modern endovascular management
Median Arcuate Ligament Syndrome
The most talked-about condition affecting the celiac trunk is median arcuate ligament syndrome, often shortened to MALS. The median arcuate ligament is a fibrous arch connecting the two diaphragmatic crura, and in some people it crosses too low, pressing down on the celiac artery where it exits the aorta. The hallmark presentation is postprandial or exercise-triggered pain in the upper abdomen, frequently accompanied by nausea, vomiting, and unintentional weight loss.15PubMed. Median arcuate ligament syndrome It tends to affect younger, leaner individuals and is more commonly diagnosed in women. In one surgical series, all patients were female with a median age in the early thirties.16PubMed. Clinico-pathologic findings in patients with median arcuate ligament syndrome (celiac artery compression syndrome)
Whether the pain comes from the artery being squeezed, the nerves being compressed, or some combination of both has been debated for decades. In that same surgical series, the celiac artery and surrounding nerves and ganglia were all found to be encased and partially compressed by fibrotic tissue, supporting the idea that nerve compression contributes to the pain and that calling it simply “celiac artery compression syndrome” undersells the picture.16PubMed. Clinico-pathologic findings in patients with median arcuate ligament syndrome (celiac artery compression syndrome)
Diagnosis typically begins with duplex Doppler ultrasound, which can measure blood flow velocities in the celiac artery during breathing. Because the ligament’s compression worsens during exhalation, when the diaphragm relaxes and pushes down, expiratory velocities tend to spike. One study found that expiratory Doppler velocities correlated significantly with visible compression on CT angiography, while inspiratory velocities did not.17Journal of Vascular and Interventional Radiology. Evaluation of Noninvasive Methods in Median Arcuate Ligament Syndrome: Doppler Ultrasound and Computed Tomographic Angiography CT angiography then confirms the diagnosis by showing the characteristic hooked or kinked appearance of the compressed artery.18PubMed Central. Real-time ultrasound: Key factor in identifying celiac artery compression syndrome
Treatment involves cutting the ligament fibers to free the artery. Laparoscopic release has become the preferred approach, with successful decompression reported in over 96% of cases in one series of 30 patients, and an overall cure rate for the condition around 80%.19PubMed. Laparoscopic Median Arcuate Ligament Release: Surgical Technique and Clinical Outcomes20PubMed Central. Laparoscopic treatment of median arcuate ligament syndrome In some cases where the artery has been chronically compressed and scarred, a stent may be placed during or after surgery. One reported case of severe MALS was successfully treated with angioplasty and stenting after the ligament was addressed.21PubMed Central. A severe case of median arcuate ligament syndrome with successful angioplasty and stenting
Celiac Artery Aneurysms
Aneurysms of the celiac artery are rare, accounting for roughly 4% of all visceral artery aneurysms.22Journal of Vascular Surgery Cases, Innovations and Techniques. Surgical repair of a symptomatic celiac artery aneurysm with resection and end-to-end anastomosis They matter because their rupture risk climbs steeply with size. For aneurysms between 15 and 22 millimeters, the rupture risk is around 5%, but once an aneurysm exceeds 30 millimeters, the risk jumps to an estimated 50 to 70%.23PubMed Central. Celiac Artery Aneurysm: A Rare Cause of Abdominal Pain Because mortality is high when these aneurysms rupture, intervention is generally recommended once the diameter exceeds 25 millimeters. Options include open surgical repair and endovascular techniques like stent placement or embolization.23PubMed Central. Celiac Artery Aneurysm: A Rare Cause of Abdominal Pain
In one series of 18 patients with celiac artery aneurysms, only one presented with a rupture. Among the nine treated surgically, there was no operative mortality. However, two saphenous vein grafts used for reconstruction occluded within months, and one patient in the nonoperative group later ruptured and died, underscoring the unpredictability of watchful waiting.24JAMA Surgery. Celiac Arterial Aneurysms: A Critical Reappraisal of a Rare Entity
Celiac Plexus Block for Cancer Pain
Because the celiac plexus is the main highway for pain signals from the upper abdominal organs, destroying or blocking it can dramatically reduce pain in conditions like pancreatic cancer. A Cochrane review found that celiac plexus block lowered pain scores compared to standard pain management at both four and eight weeks, and patients who received the block used significantly fewer opioids.25PubMed Central. Celiac plexus block for pancreatic cancer pain in adults The World Health Organization’s cancer pain relief program has endorsed the neurolytic version of this procedure, which uses alcohol or phenol to permanently destroy the nerve fibers, for patients with upper abdominal cancer pain.26The Tohoku Journal of Experimental Medicine. Celiac Plexus Block in Cancer Pain Management
The block can be performed by inserting needles through the back under CT or fluoroscopic guidance, or more recently through endoscopic ultrasound, where the needle passes through the stomach wall directly into the plexus. Endoscopic ultrasound-guided celiac plexus neurolysis has been suggested as a first-line option for patients with pancreatic cancer pain because it provides better pain control than narcotics alone and avoids the risks of a percutaneous approach through the back.27PubMed Central. Endoscopic ultrasonography guided celiac plexus neurolysis and celiac plexus block in the management of pain due to pancreatic cancer and chronic pancreatitis For chronic pancreatitis, the results are less impressive: only about half of patients get meaningful relief, and the benefit fades relatively quickly.27PubMed Central. Endoscopic ultrasonography guided celiac plexus neurolysis and celiac plexus block in the management of pain due to pancreatic cancer and chronic pancreatitis
When Tumors Invade the Celiac Axis
Pancreatic cancers arising in the body or tail of the pancreas sometimes grow directly into the celiac trunk, which in the past made them inoperable. A procedure called distal pancreatectomy with celiac axis resection, or DP-CAR, removes the distal pancreas and spleen along with the celiac trunk itself, relying on the collateral circulation through the pancreaticoduodenal arcades to keep the liver alive through retrograde flow from the superior mesenteric artery. In one series, surgeons achieved clear margins (R0 resection) in about 71% of cases, comparable to standard distal pancreatectomy rates.28PubMed Central. Distal pancreatectomy with celiac axis resection for pancreatic body and tail cancer invading celiac axis A separate institutional experience reported an even higher R0 rate of 88%, particularly when patients received chemotherapy or chemoradiation before surgery, and a median overall survival of over three years in those who had neoadjuvant treatment.29PubMed. En Bloc Celiac Axis Resection for Pancreatic Cancer: Classification of Anatomical Variants Based on Tumor Extent
This kind of surgery only works if those collateral pathways are robust enough. The surgeon typically confirms adequate retrograde flow before committing to removing the celiac trunk, often by temporarily clamping the artery and checking that the liver still has blood supply. The anatomical variants discussed earlier become extremely relevant here: if a patient’s right hepatic artery happens to arise from the superior mesenteric artery rather than the celiac trunk, for instance, the liver has an alternative supply that makes the operation safer.
Stenting for Chronic Mesenteric Ischemia
When atherosclerosis narrows the celiac trunk or the mesenteric arteries to the point that the collateral pathways cannot fully compensate, patients develop chronic mesenteric ischemia, classically described as “intestinal angina” with cramping pain after eating and progressive weight loss. Balloon angioplasty with stent placement has become a common treatment. In one single-center experience treating 45 patients, stenting provided complete symptom relief in about two-thirds and partial relief in an additional group, though a few patients had symptom recurrence within three years from stent blockage.30PubMed. Celiac and Superior/Inferior Mesenteric Angioplasty and Stenting for Chronic Mesenteric Ischemia: A Single-Center Experience The initial technical success rate is high, but long-term restenosis remains a problem. A study tracking patients over four years found that freedom from significant restenosis on strict Doppler criteria dropped to just 13% by the fourth year, even though most patients remained symptom-free because of compensatory collateral flow.31PubMed. Angioplasty/stenting of the superior mesenteric artery and celiac trunk: early and late outcomes That disconnect between recurrent narrowing on imaging and continued clinical improvement illustrates just how effective those natural backup channels are.
Traumatic Injuries to the Celiac Artery
Blunt abdominal trauma, such as from a seatbelt or steering wheel in a car crash, can occasionally tear or dissect the celiac artery. A five-year review from a level-one trauma center found only ten cases, with the most common injuries being intimal dissections and intraluminal blood clots.32PubMed. Traumatic Blunt Injuries to the Celiac Artery: A 5-Year Review From a Level I Trauma Center The vast majority of these patients, 80%, were managed without surgery, and half were sent home on aspirin alone. The collateral circulation that protects against chronic stenosis also protects in the acute setting. However, one patient in that series who was initially managed conservatively later required emergency surgery for ischemia in the bowel, liver, and stomach, a reminder that close monitoring is essential.
Management decisions in trauma hinge on patient stability, the type and extent of injury, and whether adequate collateral flow exists. Options range from simple observation and blood-thinning medication to endovascular stent placement to open surgical bypass or even ligation of the celiac trunk with reliance on retrograde flow from the superior mesenteric artery.33PubMed Central. Blunt traumatic celiac artery avulsion managed with celiac artery ligation and open aorto-celiac bypass The rarity of these injuries means there are no large trials comparing strategies, so treatment is individualized case by case.34Trauma Case Reports. Isolated celiac trunk dissection following blunt abdominal trauma: A case report and review of the literature
Celiac Trunk Abnormalities in Children With Congenital Disease
Celiac trunk anatomy takes on special importance in certain pediatric populations. In children with Alagille syndrome, a genetic condition that affects the bile ducts, heart, and blood vessels, nearly half of those studied had celiac trunk stenosis, a rate far higher than in the general population.35PubMed. Abdominal Arterial Anomalies in Children With Alagille Syndrome: Surgical Aspects and Outcomes of Liver Transplantation This creates serious challenges during liver transplantation, since the transplanted liver needs a reliable arterial supply from the celiac trunk. Surgeons working with these children must map the vascular anatomy in detail beforehand and often need creative reconstructions.
Children with congenital heart disease also show celiac trunk variants at notable rates. In one study using chest CT angiograms, about 89% had the standard three-branch pattern, but the remaining 11% showed various anomalies including gastrosplenic trunks, combined celiac-mesenteric trunks, and in a few cases complete absence of the celiac trunk.36Anales de PediatrÃa. Evaluation of coeliac trunk and hepatic artery variations in thoracic CT angiography in patients with congenital heart disease These findings reinforce that the embryological processes shaping the celiac trunk can go awry alongside other developmental programs, and that preoperative imaging should include the celiac region whenever abdominal or hepatic surgery is planned in children with known congenital conditions.