Alvin B. Vibar, M.d.

LIVER Alvin B. Vibar, M.D.

Abdominal Regions Umbilicus – level of IVD of L3 – L4 Subcostal plane – 10th rib ; L3 Transtubercular – iliac tubercle; L5 Nine regions Central – Epigastric Umbilical Hypogastric / Pubic Lateral - R/L Hypochondriac R/L Lumbar R/L Inguinal

LIVER: Surface Anatomy: lies mainly in the RUQ of the abdomen; occupies most of the R hypochondrium, the upper epigastrium & extends into the L hypochondrium

Lies deep to the 7 through 11 ribs on the R side & crosses the midline toward the L nipple Largest visceral organ & gland in the body, soft and pliable, weighs 1500 gms

Functions: Bile production and secretion Filtration of blood Involvement in metabolic activities – carbohydrate, fat and protein metabolism Blood-clotting mechanisms Synthesizes Heparin Detoxification

Surfaces: Diaphragmatic – dome shaped; anterior, superior and posterior parts; covered with visceral peritoneum except posteriorly in the bare area

Surfaces: Visceral (posteroinf.) – covered w/ visceral peritoneum except at the bed of the gall bladder & porta hepatis Related to: R side of stomach 1st part of duodenum lesser omentum Gall bladder R colic flexure & R transverse colon R kidney & adrenal gland

Impressions and structures on visceral surface of liver Renal impression Right lobe Colic impression Duodenal impression Gastric impression Left lobe Porta hepatis – central area undersurface of liver devoid of peritoneum serves as entrance for the structures in the portal triad Portal triad 1. Hepatic artery 2. Bile duct 3. Portal vein

Inferior surface and its impressions

Ligaments: Falciform ligament Coronary ligament R / L triangular ligaments Ligamentum teres / round ligament – remnant of umbilical vein; between left lobe & quadrate lobe Ligamentum venosum – remnant of ductus venosus; between left lobe & caudate lobe

Falciform ligament – 2 layered fold of – free margin contains the Ligamentum teres 2 layers: Right – Coronary ligament – Right triangular ligament Left – Left triangular ligament

Left triangular ligament Coronary ligament Bare area Right triangular ligament

Anatomical lobes: Left lobe

Right lobe – caudate & quadrate

Functional lobes: 2 – approximately equal size A line interconnecting the GB and IVC separates the Left lobe from the Right lobe Has a separate arterial blood supply, venous and biliary drainage

Hepatic Segments

Segments: Medial superior = I Lateral superior = II Lateral inferior = III Medial inferior = IV Anterior inferior = V Posterior inferior = VI Posterior superior=VII Anterior superior=VIII

ABDOMINAL AORTA Anterior Visceral Celiac Superior Mesenteric Inferior Mesenteric Lateral Visceral Suprarenal Renal Gonadal Lateral Abdominal Inferior Phrenic Lumbar Terminal branches Common iliac Median Sacral

Celiac artery – T 12 Left Gastric Splenic – Left Gastroepiploic Short Gastric Hepatic – Right Gastric R/L Hepatic Gastroduodenal – Right Gastroepiploic Sup. Pancreaticoduodenal

Superior Mesenteric Artery – L 1 Inferior Pancreaticoduodenal Middle Colic Right Colic Ileo-colic Jejunal-Ileal

Inferior Mesenteric Artery – L 3 Left Colic Sigmoid Superior Rectal

PRIMITIVE GUT divisible into: FOREGUT – supplied by Celiac trunk MIDGUT – Sup. Mesenteric artery HINDGUT – Inf. Mesenteric artery

Foregut derivatives Primordial pharynx and it’s derivatives ( oral cavity, pharynx, tongue, tonsils, salivary glands, upper respiratory ) Lower respiratory Esophagus and Stomach Duodenum ( proximal to the opening of bile duct ) Liver, Biliary apparatus ( hepatic ducts, Gall bladder and Bile duct ) and Pancreas Supplied by Celiac artery

Midgut derivatives Small intestine, including most of the duodenum Cecum, Vermiform appendix, Ascending colon, and the right half to two thirds of the Transverse colon Supplied by Superior mesenteric artery

Hindgut derivatives Left one third to one half of the transverse colon Descending colon and Sigmoid colon Rectum and Superior part of the Anal canal Epithelium of the Urinary bladder and most of the Urethra Supplied by Inferior mesenteric artery

Blood supply to liver Common Hepatic artery divides into Right and Left hepatic arteries supplying the Right and Left functional lobes of the Liver

Blood supply: Portal vein – formed by union of superior mesenteric & splenic veins ; 70% Hepatic artery – branch of celiac artery; 30%

Blood Flow to liver Portal vein - 70% blood flow - unoxygenated blood , absorbed substance from the alimentary tract - will drain to the hepatic veins Hepatic artery - 30% blood flow - oxygenated blood - branch of the celiac artery from abdominal aorta

Hepatic lobule

Liver Acinus Divisible into 3 zones: Zone 1 – closest to the portal tract and receives the most O2 Zone 2 Zone 3 – farthest and receives the least O2, most susceptible to ischemic injury

LIVER

PORTAL VENOUS SYSTEM Tributaries: Superior mesenteric Splenic Inferior mesenteric Left gastric Paraumbilical

Tributaries of the Portal Veins

Venous drainage, lymphatic & nerve supply Hepatic veins formed by the union of central veins drain into IVC Hepatic lymph nodes drain into celiac lymph nodes – cisterna chyli Hepatic nerve plexus from celiac plexus

Portal-Caval Anastomoses Normal route – portal vein – liver – hepatic vein – IVC If blocked: Esophageal branch of L gastric = esophageal of Azygos Superior rectal = middle & inferior rectal Paraumbilical = superficial veins of ant. Abd’l wall Colic veins = retroperitoneal veins

Portal Hypertension

Azygous vein

Left gastric vein

Esophageal plexus of veins Para-umbilical veins Hemorrhoidal plexus of veins

Clinical Correlation: Liver biopsy usually done at R 10th ICS in MAL Rupture of liver Hepatomegaly Liver cirrhosis – causes portal HPN w/c can produce esophageal varices, caput medusae and hemorrhoids

PANCREAS

Pancreas ( exocrine and endocrine)

Parts Head – expanded part; is embraced by the C shaped curve of the Duodenum Neck – short and overlies the Superior mesenteric vessels Body – to the left of SMA and SMV Tail – closely related to the hilum of spleen and left colic flexure

Parts of the Pancreas Head Neck Body Tail Uncinate process – projection from the inferior part of head; extends medially to the left post. to SMA

Relations: Lies Posterior to the Stomach between the Duodenum on the right and Spleen on the Left

Ducts of the Pancreas Main pancreatic duct (Wirsung) begins in the tail of the pancreas and runs through the parenchyma to the head where it turns inferiorly and merges with the Bile duct

Blood supply: Superior pancreaticoduodenal artery from Gastrodudenal ( Hepatic – Celiac) Inferior pancreaticoduodenal from SMA Pancreatic arteries from Splenic

Blood supply of Pancreas

Blood supply to the body and tail

Venous drainage: Pancreatic veins which are tributaries of the Splenic and Superior mesenteric; most of them empty into the Splenic vein

Rupture of the Pancreas Pancreatic injury can result from sudden, severe, forceful compression of the abdomen Rupture frequently tears its duct system allowing pancreatic juice to enter the parenchyma of the gland and to invade adjacent tissues – digestion of pancreatic and other tissues by pancreatic juice is painful

Pancreatic cancer Cancer involving the pancreatic head accounts for most cases of extrahepatic obstruction of the biliary system Compresses and obstructs the Bile duct causing Obstructive jaundice resulting in the retention of bile pigments, enlargement of GB and jaundice