Celiac Trunk & Associated Viscera Notes

Celiac Trunk & Associated Viscera

ANA6304 Gross Anatomy
Jessica Walker, PhD
Modified by Dr. Zumpano
Northeast College of Health Sciences

Food Passage and Digestive System

Mouth
Pharynx
Esophagus
Stomach
Small intestines
- Duodenum
- Jejunum
- Ileum
Large intestines
- Cecum
- Ascending colon
- Transverse colon
- Descending colon
- Sigmoid colon
- Rectum
- Anal canal
Foregut – celiac trunk
Midgut – superior mesenteric artery
Hindgut – inferior mesenteric artery

Celiac Trunk Branches

Left Gastric
Splenic
- Left gastro-omental
Common Hepatic
- Proper Hepatic
  - Right gastric
  - Right Hepatic
    - Cystic
  - Left Hepatic
- Gastroduodenal
  - Right gastro-omental
  - Superior pancreaticoduodenal

Hepatobiliary Apparatus

Liver, Gall bladder and ducts
Epiploic foramen (Winslow)
- Anterior: Free lesser omentum with bile duct, portal v. and proper hepatic a.
- Posterior: inferior vena cava
- Superiorly: caudate process of liver
- Inferiorly: first part of duodenum

Esophagus

Esophageal hiatus at level of T10
Phrenico-esophageal ligament
Cardial orifice of stomach
Left of midline at level of 7th costal cartilage & T11
Z-line
Mucosa changes from esophageal to gastric

Esophageal Constrictions

Upper esophageal constriction (cervical constriction) at C6-C7
Middle esophageal constriction (thoracic constriction) at T3-T4
Lower esophageal constriction (abdominal constriction) at T10-T11

Esophagus Muscle Composition

Combination of skeletal and smooth muscle.
- Skeletal Muscle:
  - upper third of the esophagus
  - upper esophageal sphincter (UES) which is responsible for opening and closing the entrance to the esophagus during swallowing. This part is under conscious control.
- Smooth Muscle:
  - lower third of the esophagus
  - lower esophageal sphincter (LES), which prevents stomach acid from flowing back into the esophagus. This portion is under involuntary control.
- Mixed Muscle:
  - middle third of the esophagus contains both

Esophagus Blood Supply & Innervation

Blood Supply of abdominal portion
- Arterial
  - Left gastric artery
  - Left inferior phrenic artery
- Venous
  - Portal system (left gastric vein)
  - Vena caval system (azygos vein)
Innervated by esophageal plexus
- Parasympathetic: vagus nerve
- Sympathetic: greater splanchnic nerve
Lymph
- Left gastric & celiac lymph nodes

Stomach

Food blender & reservoir
Holds 2-3 L of food
Enzymatic digestion
Chyme
Peristalsis
Smooth muscle contractions
Lesser curvature
Greater curvature
Gastric canal (along lesser curvature)
Gastric rugae (folds)
Cardia
- Superior opening of the stomach
- Cardial orifice
- Posterior to left 6th costal cartilage at the level of T11
Fundus
- Posterior to left 6th rib in MCL plane
- Dilated by gas, food, or fluid
- Cardial notch separates fundus & esophagus
Body
- Region between fundus and pyloric antrum
Pyloric part
- Pyloric antrum
- Pyloric canal
- Pyloric sphincter (pylorus)

Stomach – Arterial Supply

Celiac Trunk branches
- Left & right gastric a. anastomose along lesser curvature
- Left & right gastro-omental a. anastomose along greater curvature
- Short & posterior gastric arteries
- Branches of splenic a.

Stomach – Venous Drainage

Venous
- Mirrors arterial supply
- All veins drain to portal vein
- Prepyloric vein
  - Travels over pyloric sphincter to right gastric vein

Stomach – Innervation

Sympathetic
- Greater splanchnic nerve (T6-T9)
- Celiac plexus
- Celiac ganglion
Parasympathetic
- Anterior vagal trunk
  - Hepatic, duodenal & anterior gastric branches
- Posterior vagal trunk
  - Celiac branch to celiac plexus
  - Posterior gastric branches

Duodenum

Latin for “12 fingers” (~25 cm)
First (and shortest) part of small intestines
Forms “C” around head of pancreas
4 anatomical parts
- Superior
- Descending
- Inferior
- Ascending

Duodenum Parts & Vertebral Landmarks

First part
- Anterolateral to L1 (5 cm)
- First 2 cm = ampulla (duodenal cap)
- Intraperitoneal
  - Hepatoduodenal ligament attaches to ampulla
- Distal 3cm secondarily retroperitoneal
Second part
- Descending (2nd) part (~7-10 cm)
- Descends along right side of L1-L3
- Hepatopancreatic ampulla
- Major duodenal papilla/ Sphincter of Oddi
- Secondarily retroperitoneal
Third part
- Inferior (3rd) part (~6-8 cm)
- Crosses L3 vertebrae
- Inferior to head and uncinate process of pancreas
- Secondarily retroperitoneal
Fourth part
- Ascending (4th) part (~5 cm)
- Left of L3, then rises to superior border of L2
- Secondarily retroperitoneal
- Joins jejunum at duodenojejunal flexure
- Suspensory ligament of duodenum (ligament of Treitz)
- Superior duodenal flexure at L1
- Inferior duodenal flexure at L3

Duodenum Blood Supply & Innervation

Arterial = Celiac Trunk branches
- Gastroduodenal
- Superior pancreaticoduodenal
Superior mesenteric artery
- Inferior pancreaticoduodenal
Veins mirror arteries and drain to portal vein
Innervation
- Celiac and superior mesenteric plexus
  - Parasympathetic - Vagus nerve
  - Sympathetic - Greater and lesser splanchnic nerves

Liver

Largest gland & second largest organ (~2.5% of body weight)
Processes nutrients absorbed in gastrointestinal tract
Produces bile, glucose, glycogen, albumin, clotting factors, cholesterol
Right upper quadrant
Deep to ribs 7-11
Diaphragmatic & visceral surfaces

Liver Lobes & Fissures

Four lobes
- Right lobe
- Left lobe
- Caudate lobe
  - Caudate process
    - Between IVC and porta hepatis
    - Connects right & caudate lobes
- Quadrate lobe
Fissures
- Right
- Left

Liver Ligaments

Falciform ligament
- Divides right & left lobes
- Ventral mesentery
- Round ligament of liver
  - a.k.a. ligamentum teres hepatis
  - Remnant of umbilical vein
Coronary ligament
- Anterior & posterior portions
- Surrounds the bare area of liver
Right triangular ligament
Left triangular ligament
Fissure for ligamentum venosum
- Remnant of ductus venosus

Liver Features

Groove for vena cava – IVC
Fossa for gallbladder
Portal triad (porta hepatis)
- Contained within hepatoduodenal ligament
  - Contents:
    - Bile duct – anterior and right
    - Proper hepatic artery & branches
    - Portal vein - posterior

Liver – Blood Supply

Portal (hepatic portal) vein (75-80%)
- Nutrient-rich
- SMV & splenic vein (plus IMV)
- Posterior to neck of pancreas
Hepatic artery (20-25%)
- Proper hepatic artery
  - Right hepatic artery
  - Left hepatic artery
Hepatic veins
- Right, intermediate (middle), and left
- Drain into IVC

Liver – Innervation & Bile Transport

Innervated by hepatic plexus
- Derivative of celiac plexus
  - Parasympathetic – anterior & posterior vagal trunk
  - Sympathetic – greater splanchnic nerves
  - Surrounds hepatic artery
Common hepatic duct (bile)
- Right & left hepatic ducts
- Cystic duct
  - Communicates to gallbladder for bile transport

Gallbladder

Stores & concentrates bile
Holds 50 ml
Fundus
Body
Neck
Spiral fold (valve)
Blood supply from cystic artery
- Branch of right hepatic artery
Cystic vein to hepatic portal vein
Innervated by celiac plexus

Bile Pathway

Bile duct + Pancreatic duct = Hepatopancreatic ampulla (of Vater)
Major duodenal papilla (Sphincter of Oddi)

Pancreas

Secondarily retroperitoneal
Lies transversely across L1-L2 (at level of transpyloric plane)
Posterior to stomach
Between duodenum (right) and spleen (left)
Exocrine gland
- Pancreatic juice
Endocrine gland
- Insulin and glucagon

Pancreas Parts

Head
- Encircled by C-shape of duodenum
- Right of superior mesenteric vessels
Uncinate process
- Projection inferior to head
- Posterior to SMA
Neck
- Anterior to superior mesenteric vessels
Body
- Passes over aorta and L2
Tail
- Anterior to left kidney, close to splenic hilum & left colic flexure

Pancreas Ducts, Blood Supply, & Innervation

Main pancreatic duct
- Runs from tail to head
- Joins bile duct at hepatopancreatic ampulla
- Opens into duodenum at major duodenal papilla
Accessory pancreatic duct
- Opens at minor duodenal papilla
Blood supply
- Splenic artery branches, superior pancreaticoduodenal arteries & inferior pancreaticoduodenal arteries (SMA branch)
Venous drainage into splenic vein
Innervated by superior mesenteric plexus and celiac plexus

Spleen

Upper left quadrant
Largest lymphatic organ
Lymphocyte proliferation
Immune surveillance
RBC removal and destruction and recycling
Blood reservoir
Rests near left colic flexure
Left 9-11 ribs
Splenic capsule
Splenic hilum
- Splenic artery and vein
Trabeculae
Splenic Pulp
- White
- Red

Spleen Ligaments, Blood Supply, & Innervation

Gastrosplenic ligament
- Greater omentum
- Connects stomach to spleen
- Contains short gastric & left gastro-omental vessels
Splenorenal (lienorenal) ligament
- Connects spleen to left kidney
- Contains splenic artery
Arterial Supply
- Splenic artery
  - Largest artery of the celiac trunk
  - Tortuous artery runs posterior to omental bursa (lesser sac) along superior border of pancreas
Venous Drainage
- Splenic vein
  - Inferior Mesenteric Vein drains into
  - Joins with Superior Mesenteric Vein to form hepatic portal vein
Innervated by celiac plexus