Biliary System and Liver Biliary System and Liver 8/21/2015

Liver Largest gland of body –(any organ that secrets enzymes is a gland - all glands are organs) 2nd largest organ- (group specialized tissues performing specific function or function) What is the 1 st ? Skin How much does it weigh? Approx. 3 lbs

Liver is only internal human organ capable of natural regeneration of lost tissue! as little as 25% of a liver can regenerate into a whole liver Not true regeneration! Not true regeneration! lobes removed do not regrow- function is restored, but not original form (aka: compensatory growth) (in true regeneration, both original function and form are restored)

Fatty liver Normal liver Cirrhosis Cirrhosis can occur in non-drinkers

2 major lobes: Right lobe Left lobe 2 minor lobes: 2 minor lobes: Caudate lobe- part of right lobe -posterior Caudate lobe- part of right lobe -posterior Quadrate lobe - part of right lobe -inferior Quadrate lobe - part of right lobe -inferior Falciform ligament divides liver into :

Functions of liver Main function -formation of bile Main function -formation of bile Not on midterm or final : (Filter harmful substances from blood (alcohol) Maintain a proper level of glucose in blood Convert glucose to glycogen Produce urea Make certain amino acids Store vitamins and minerals Produce 80% of cholesterol )

It has a dual blood supply! It has a dual blood supply! 1. From Hepatic artery- Liver gets oxygenated blood from Liver gets oxygenated blood from abdominal aorta to like any other part of body abdominal aorta to like any other part of body 2. From Portal vein- (Portal system) Liver receives deoxygenated blood from digestive Liver receives deoxygenated blood from digestive organs (stomach, spleen, intestinal tract, gall bladder and pancreas ) organs (stomach, spleen, intestinal tract, gall bladder and pancreas ) Modifies and filters it Modifies and filters it Sends it back by hepatic veins to heart where it is circulated to rest of body Sends it back by hepatic veins to heart where it is circulated to rest of body What is unique about liver?

Big Problem! Many drugs taken orally are substantially metabolized by portal system of liver before reaching general circulation! Known as “First Pass Effect” Known as “First Pass Effect” Thus certain drugs can only be taken via certain other routes! 1. Sublingual Example: Nitroglycerin cannot be swallowed - liver would inactivate medication -must be taken under tongue or transdermally (patch) Example: Nitroglycerin cannot be swallowed - liver would inactivate medication -must be taken under tongue or transdermally (patch)

Alternate ways to take meds (cont’d) 2. Intravenously 3. Intramuscularly 4. Aerosol inhaler 5. Suppository

What is the Biliary System? Consists basically of : 1. gallbladder 1. gallbladder 2. bile ducts 2. bile ducts The Excretory system of liver!

Biliary Combining Forms chole – relationship with bile (aka: gall) bladder – sac or bag, serving as receptacle for a secretion cyst – closed sac having distinct membrane and division with nearby tissue docho – duct – tube or passage way for conducting a substance angio – vessel graph- representation of a set of objects - iasis – presence of - itis – inflammation of

What is Bile? Greenish-yellow fluid produced in liver Greenish-yellow fluid produced in liver (consists of waste products, cholesterol, and bile salts) (consists of waste products, cholesterol, and bile salts) (when excreted gives feces dark brown color) (when excreted gives feces dark brown color) 2 Primary Functions of Biliary System: Aids in digestion- by controlling release of bile Drains waste products from liver into duodenum

Gall bladder Reservoir for bile from liver – 2oz. capacity (50 percent of bile is stored in gallbladder) How does bile get into gallbladder ? Sphincter of Oddi closes up, and bile is re- routed up into GB for temporary storage when not needed How much bile does liver produce per day? 1-3 pints

Transportation of bile sequence Liver secretes bile- into right and left hepatic ducts join to become common hepatic duct right and left hepatic ducts join to become common hepatic duct which joins with cystic duct from gallbladder to become the: common bile duct which joins with pancreatic duct to form a junction known as: hepatopancreatic ampull a (or ampulla of vater Spincter of Oddi (or spincter of hepatopancreatic ampulla) controls emptying of bile into duodenum

Gallstones Hardened deposits of digestive fluid that can form in gallbladder Range in size from grain of sand to a golf ball Can have one or hundreds! 1 in 10 people have gallstones (can’t see if not calcified!)

Two types of gallstones 80% are cholesterol stones: usually yellow-green and made primarily of hardened cholesterol usually yellow-green and made primarily of hardened cholesterol 20% are pigment stones: small, dark stones made of bilirubin

Risk Factors for Gallstones Female Female Age 60 or older Age 60 or older American Indian or Mexican heritage American Indian or Mexican heritage Overweight or obese Overweight or obese Pregnant Pregnant Eating a high-fat, high-cholesterol, or low fiber diet Eating a high-fat, high-cholesterol, or low fiber diet Family history of gallstones Family history of gallstones Diabetes Diabetes Losing weight very quickly Losing weight very quickly Taking cholesterol-lowering medications Taking cholesterol-lowering medications Taking medications containing estrogen (such as hormone therapy drugs) Taking medications containing estrogen (such as hormone therapy drugs)

Complications from Gallbladder Stones! Choledocholithiasis - presence of bile stones in ducts Cholecystitis - bile sac inflammation Pancreatitis Can cause increased risk of gallbladder cancer (very rare)

Treatment for Gallstones Use medicines to dissolve stones (isn't suitable for everyone -may take a very long time) Shock-wave lithotripsy - high-energy sound waves break gallstones into tiny fragments, then dissolve by medicines Cholecystectomy - Surgical removal of gallbladder

If your gallbladder is removed… No longer have a holding space to store bile! Most animal species don’t even have one! Bile continuously runs out of liver, through hepatic ducts, into common bile duct, and directly into small intestine When a high-fat meal is eaten - not enough bile available to digest it properly – (may resolve in time) When a high-fat meal is eaten - not enough bile available to digest it properly – (may resolve in time) Small intestine’s ability to absorb essential fatty acids, vitamins and minerals is compromised Can result in chronic diarrhea

Release of bile from gallbladder is stimulated by secretion of hormone: “cholecystokinin” When food containing fat enters digestive tract…

Pancreas Both an exocrine and endocrine gland! Endocrine- (Isle of Langerhans) produces glucagon and insulin to regulate sugar metabolism Exocrine- secretes digestive enzymes Generally cannot be seen on radiographs

Radiologic Exams of Biliary System ( largely replaced by Ultrasound, CT, MRI, nuclear medicine)

Cholecystography Study of gallbladder Oral contrast is used Cholangiography Study of biliary ducts IV contrast is used 2 Basic Types of Radiological Exams of Biliary System

Indications for Biliary Tract Exam Cholelithiasis (gallstones) -bile calculi presence Cholecystitis (inflammation of gallbladder)-bile sac inflammation Check liver function Biliary neoplasia (tumor or mass in biliary system) Biliary stenosis (abnormal narrowing of ducts) Demonstrate concentrating/emptying ability of gallbladder

Patient Prep Fat -free meal evening before (don’t want GB to empty) Oral contrast taken 2 to 3 hours after evening meal to be absorbed by GB NPO after midnight until exam No laxatives less than 24 hours before exam to avoid prevent voiding of contrast medium! Early morning appointment

Position of Gallbladder RUQ RUQ In hypersthenic pt. In hypersthenic pt. Superior and lateral Superior and lateral In Asthenic In Asthenic Inferior and nearer to spine Inferior and nearer to spine

Shielding Review What 3 things must you consider? 1. Are gonads within 2” of primary x-ray field after proper collimation? 2. Are clinical objectives compromised? 3. Does pt have reasonable reproductive potential?

Cholecystogram Cholecystogram ( Gallbladder Exam) Scout film (the one time you should see gall bladder in image if pt prepped properly) PA, RAO, R Decub Dr. may do fluoroscopic examination Post-fatty meal image may be obtained to demonstrate emptying ability of GB

PA Projection Patient prone- or upright facing wallboard Center 10x12 cassette at RUQ, level of the right elbow kVp range Exposure made at end of full expiration

PA Oblique Projection LAO position Pt rotated degrees depending on body habitus CR at level of elbow, between spine and R midaxillary line 10x12 cassette

Rt. Lateral Decubitus Demonstrates stones lighter than bile visible only by stratification CR: Directed horizontally to level of gallbladder

Intravenous Cholangiography (IVC) ( Very rarely performed anymore) Radiologic procedure to: look at bile ducts coming from liver locate any gallstones passed into the bile ducts identify other causes of obstruction of flow of bile Used when pts can’t tolerate oral contrast Used when pts can’t tolerate oral contrast Iodine-containing dye is injected intravenously (or directly) to outline ducts and gallstones 3 types we’ll talk about:

Percutaneous Transhepatic Cholangiography (performed preoperatively) Performed when ductal system shown to be obstructed by CT or Ultrasound Contrast is injected directly into bile ducts using long needle (chiba)) through abdominal wall and liver under fluoro Decision is made to drain biliary ducts, extract stones, or possibly leave catheter in for long te rm drainage ( Percutaneous : any medical procedure where access to inner organs or other tissue is done via needle- puncture of skin, rather than by scapel)

Cholangiography Intra-operative Obtained during a cholecystectomy Examines patency of ducts and functionality of Spincter of Odi during or after surgical removal of GB

T-Tube Cholangiography Post-operative (after cholecystectomy) procedure performed through T-tube left in common hepatic and common bile ducts (for drainage) To determine: patency (openness) of biliary ducts after cholecystectomy patency (openness) of biliary ducts after cholecystectomy status of Spincter of oddi status of Spincter of oddi presence of residual or undetected stones presence of residual or undetected stones

Intraoperative (during) Percutaneous (before surgery) 3 Cholangiogram types compared T-Tube (post)

ERCP Used to diagnose biliary and pancreatic pathologic conditions when ducts are not dilated and ampulla is not obstructed Fiberoptic endoscope passed through mouth into duodenum under fluoroscopy Common bile duct is catheterized Contrast is injected Stones can be removed at same time Endoscopic Retrograde Cholangiopancreatography Endoscopic Retrograde Cholangiopancreatography