Module 3 : Liver Flashcards
1
Q
Liver - location
A
- intraperitoneal
- largest organ in the body
- RUQ
- right hypochondrium, epigastric, left hypochondrium
2
Q
Liver - superior margins
A
- bordered superiorly by diaphragm
- superior anterior posterior surface of liver are in contact with the diaphragm
3
Q
Liver - inferior surface
A
- in contact with viscera, rests on upper abdominal organs
4
Q
Liver - posterior surface
A
- indented by right kidney
- ## IVC is posterior
5
Q
Liver- displacement
A
Caudally - tumors - cirrhosis - subphrenic abscesses Cranially - abdominal tumor - ascites - excessive dilatation of colon
6
Q
Liver - shape and size
A
- varies in size and shape dependent on body habitus
- right lobe 2-3 times larger than left lobe in size
- left lobe varies in size and shape
+ wedge shaped
7
Q
Liver - measurement
A
- length (midclavicular line - from diaphragm to inferior edge)
- = 15.5
- AP at mid point of longitudinal measurement
- 8.1 +/- 1.9 S.D
- Caudate/ RT Lobe ratio (subcostal true transverse)
- < 0.65
8
Q
Liver enlarged if…
A
- Rt lobe extends below lower pole of right kidney
- except with reidels lobe
9
Q
Reidels lobe
A
- tongue like extension of inferior tip of Rt lobe of liver, frequently found in slim females
10
Q
Lobar anatomy - anatomical
A
- not typically used in medicine
- based on external markings
- 4 lobes: quadrate , caudate, right and left
- falciform ligament divides right and left lobes
11
Q
Anatomical division - caudate and quadrate
A
Caudate - lies between IVC, LIG venosum, and Portal Vein
Quadrate - porta hepatis, gallbladder fossa, LIG teres
12
Q
Functional division
A
- based on blood supply and biliary drainage (important for surgical reasons)
- ligaments, fissures, and gallbladder as landmarks
- 3 lobes and 4 segments
+ right lobe : anterior posterior
+ left lobe : lateral medial
+ caudate
13
Q
Functional - intrasegmental
A
- right and left portal veins course WITHIN the segments
14
Q
Functional - Intersegmental
A
- right left and middle hepatic veins course between the lobes and segments
- INTERLOBAR
15
Q
Functional - right lobe
A
- separated by left lobe by main lobar fissure
+ middle hepatic vein courses through MLF - divides into anterior posterior segments by right Intersegmental fissure
+ right hepatic vein and right portal vein course though RIF
= anterior Right Portal within anterior Right Lobe
= posterior right portal within posterior right lobe
16
Q
Functional - left lobe
A
- divided into medial and lateral segments by left Intersegmental fissure
+ left hepatic vein, left portal and LIG teres run through LIF - medial left lobe considered quadrate lobe
17
Q
Functional - caudate lobe
A
- receives portal venous and hepatic arterial blood from both right and left systems
- located on the posterior aspect of the liver
- posterior landmark = IVC
- anterior landmark = LIG venosum
- structure directly inferior = MPV
18
Q
Functional- caudate process
A
- portion of the caudate that extends to the right obliquely and passes between the IVC and portal vein
- everyone has one
19
Q
Functional - papillary process
A
- caudal projection of the caudate lobe
- not on everyone
20
Q
main lobar fissure
A
- divides liver into functional right and left lobes
- gallbladder and IVC used as landmarks
- short portion of the main lobar fissure is identified between the right portal vein and gallbladder neck in sagittal
- middle hepatic vein courses through it
21
Q
- right intersegmental fissure
A
- divides right lobe into anterior and posterior segments
- right hepatic vein and portion of rpv course through it
22
Q
left intersegmental fissure
A
- divides the left lobe into medial and lateral segments
- fissure divided into cranial middle and caudal
+ left hepatic vein courses within the cranial third
+ ascending branch of left portal vein represents middl third
+ lig teres divides caudal portion
23
Q
fissure for the ligamentum venous
A
- divides the left lateral segment from the caudate lobe
- contains lig venosum (remnant of ductus venous)
- contains hepatogastric ligament (makes up lesser omentum)
24
Q
gallbladder fossa
A
- contains gall bladder
- located on posterior inferior portion of right lobe of liver
- closely related to main lobar fissure
25
inferior vena cava fossa
- contains portion of IVC
| - depression on posterior surface of the liver between the caudate and bare area
26
porta hepatis
- main vessel and biliary ducts leave and enter the liver at this point
- COMMON BILE DUCT AND HEPATIC ARTERY ARE ANTERIOR TO PORTAL VEIN
27
glissons capsule
- thin layer of connective tissue surrounding the liver
| - thickest at IVC and porta hepatis
28
hepatoduodenal ligament
- a fold of lesser omentum
+ with hepatogastric is full lesser omentum
- anterior boundary of epiploic foramen
+ connection between greater and lesser sac
- 3 structures within HL
+ main portal vein, hepatic artery, CBD
29
falciform ligament
- extends from umbilicus to liver
- attaches the diaphragm to the superior surface of the liver
- conducts fetal umbilical vein
30
ligamentum teres (round ligamnetum)
- inferior margin of the liver
| - atrophied umbilical vein
31
ligamentum venosum
- remnant of the fetal ductus venosum
| - anterior border of the caudate lobe
32
coronary ligaments
- defines bare area of liver
- connects the posterosuperior surface of the liver to the diaphragm upper portion continuous with falciform ligament
- forms right and left triangular ligament
33
portal veins
- carry partially oxygenated blood from intestines, spleen, pancreas, GB and bowel
- travel intrasegmentally (within the segments)
- echogenic reflective walls (connective tissue surrounding portal triad)
- vessel caliber is greater near porta hepatis
34
main portal vein
- formed by conjunction of splenic vein, SMV, IMV
- travels to the right in a cephalic oblique
- divides into the right and left portal vein at porta hepatis
35
right portal vein
- anterior and posterior branches
- travels posterior and caudally
- can appear as elongation of MPV
36
left portal vein
- moves cranially along the anterior surface of the caudate lobe and then turns anterior
- divides into medial and lateral branches
- steers head
37
hepatic veins
- carry deoxygenated blood from the liver to the IVC
- drain toward right atrium
- travel intersegmentally (between lobes)
- caliber increases as the approach diaphragm and IVC
- do NOT have echogenic walls
38
right hepatic vein
- Largest
| - travels in right intersegmental fissure
39
left hepatic vein
- smallest
| - travels in left intersegmental fissure
40
middle hepatic vein
- travels in main lobar fissure
41
sonographic appearance
- homogenous with fine to medium level echoes
- MINIMALLY HYPERECHOIC OR ISOECHOIC WHEN COMPARED TO RIGHT RENAL CORTEX
- fissures and ligaments are highly echogenic
- portal vein walls are echoic
42
patient prep and scanning
- over night fast NPO
- supine of LLD
- subcostal and intercostal
- big breath in and hold
- curvilinear
- sag and trans assessment
- attention to size, texture, vasculature, and biliary structs
43
lobule
- FUNCTIONAL UNIT OF THE LIVER
- 1 to 2 mm in diameter
- consists of
+ hepatocytes
+ central hepatic vein
+ sinusoids
+ kupffer cells
+ bile canaliculi
+ portal triads
44
hepatocytes
- organized in two layered columns converging toward a central vein in a radial pattern
- in contact with sinusoid blood
- liberate substances into the blood
- make up most of liver tissue
45
sinusoids
- blood enters periphery of lobule and travels to central vein via sinusoid
- located between hepatocyte and colomns
- consists of 80% portal venous blood and 20% hepatic blood
46
kupffer cells
- scattered along sinusoids
- part of reticuloendothelial system (defensive)
- ingest and destroy foreign material (phagocytosis)
- cleanse blood
47
bile canaliculi
- between 2 layers of liver cell columns
- smalles division of biliary tract
- bile liberated from hepatocytes into canaliculi flowing toward the later bile duct outer edge of liver lobule
- bile duct is always separated from the sinusoid blood
- converge to form larger ducts then unite to form right and left hepatic ducts
48
portal triad
- consist of bile duct, portal vein, and hepatic artery
- at outer edge of lobule
- several portal triads in single lobule
49
central hepatic vein
- blood enters periphery of lobule and travels toward the central vein via the sinusoids
- blood in central vein should be cleansed of toxins and rich in lover secretions
- converge into larger veins which unite into hepatic veins draining into IVC
50
function of liver
- primary centre of metabolism
- performs about 500 separate activities
- functions carried out via hapetocytes, kupffer cells, biliary cells
51
bile formation and secretion
- bilirubin is a product of red blood cell breakdown
- bile salts are formed froth cholesterol in hepatic cells
- bile emulsifies fats and aids in absorption of fatty acids
- 700 to 1200ml / day
52
bilirubin
```
- unconjugated bilirubin
+ indirect
+ fat soluble
+ not excreted into urine
+ toxic to tissues
- conjugated bilirubin
+ direct
+ non toxic
+ water soluble
+ secreted by liver into bile canaliculi
```
53
reticuloendothelial function/immune system
- produces blood cells in the embryo (hemopoiesis)
- produces plasma protein and antibodies
- remove foreign material and worn out red blood cells via kupffer cells (phagocytosis)
- recovers bile pigment
54
metabolism
- carbohydrate
+ glucose buffer
- fat
- protein
55
storage depot
- vitamin A, D, B12
- glycogen, fats, amino acids
- ferritin (derivative of iron)
- copper and iron
+ poison
56
blood reservoir
- can store 200 - 400 ml
57
heat production
- produces heat result of chemical reactions
58
detoxification
- alcohol
59
lymph formation
- one third to half of body lymph fluid
60
lab tests
- test for enzyme
61
enzyme
- protein that catalyze chemical rxn
- accelerate and control rxn rates = not destroyed
- diff cells produce diff enzymes
- tissue cell damage >> enzyme in blood streams
- reflect function of body
- blood (serum) & urine
62
ALT / SGPT
- enzyme porduced in hepatocytes
- SPECIFIC INDICATOR FOR HEPATOCELLULAR DAMAGE
- used with AST to distinguish between cardiac and hepatic damage
- increased values seen in hepatitis, cirrhosis, tutors, hepatotoxicity
63
AST / SGOT
- found in liver, muscle and tissue with high metabolic rates
- released with injury to cells in tissue
- increased values in hepatitis , cirrhosis, hepatotoxicity, myocardial infarction
64
ALP or Alk Phos
- enzyme in liver bone placenta
- BILIARY OBSTRUCTION
- ALP INCREASED WITH NORMAL AST AND ALT INDICATES DISEASE OF BILE DUCT
65
LDH
- multiple organ systems
- usually used to detect myocardial infarctions or pulmonary infarcts
- increase in hepatitis cirrhosis instructive jaundice
66
GGT
- nonspecific indicator of hepatic disease
| - SENSITIVE TO EFFECTS OF ALCOHOL IN LIVER
67
AFP
- produced in fetal tissue
- PROTEIN
- INCREASED VALUES IN HEPATOCELLULAR CARCINOMA AND TESTICULAR CARCINOMA
68
BILIRUBIN
- breakdown product of hemoglobin
- values consist of
+ total bilirubin
- combined conjugates and unconjugated bilirubin
- increase in hepaticelluar damage
+ unconjugated/indirect
- elevated in hepatocellular disease and hemolytic anemia
+ conjugated/direct
- ELEVATED IN EXTRAHEPATIC BILE DUCT OBSTRUCTION
69
PROTHROMBIN TIME (PT)
- clotting factor affected by levels of vitamin K
- ability of blood to clot
- prolonged in nonfunctioning or scarred liver and lack of vitamin K
- also prolonged with anticoagulant therapy
70
INR (internation normalized ratio)
- ratio used in place of PT
| - greater than 1.2 liver biopsies should not be done
71
PTT
- measures clotting time of blood
72
SERUM PROTEIN
- albumin is a PROTEIN synthesized by the liver and maintains osmotic pressure in blod
- decreased levels seen in liver dysfunction
73
HEPATITIS TESTING
- used to determine is patient has been exposed to or currently infected with or carrier of viral hepatitis
- hep A or B
- hep non A or non B
