Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
32 Cards in this Set
- Front
- Back
- 3rd side (hint)
|
What are the 3 different Liver Spleen scans?
|
Hemangioma
Spleen Hepatobiliary which includes ejection fraction |
|
|
|
What are the 4 lobes of the liver?
|
Right
Left Quadrate Caudate |
|
|
|
Explain the blood flow to the liver and what is meant by 2 vessels and a duct?
|
Between the lobules is the hepatic triad (2 vessels and a duct) which are the PORTAL VEIN, hepatic artery and a bile duct. 3/4 of the blood comes from portal vein, from digestive system rich in nutrients and 1/4 is from the hepatic artery rich in oxygen
|
|
|
|
Why is there a reservoir for blood in the liver and how much does it hold?
|
Blood can be added to it or taken out of circulation as a pressure regulator, it holds 500ml
|
|
|
|
What is the porta hepatis?
|
It contains the hepatic artery, portal vein and bile ducts
|
|
|
|
What are the 5 functions of the liver?
|
1. secretes and excretes bile from hepatic cells
2. regulate blood volume, and stores erythrocyte maturing factor in development of RBC 3. Stores vitamins A, D, B12, copper, iron, magnesium and glucose next----> |
4. metabolic: synthesizes glycogen, converts it to glucose, fat metabolism, synthesizes cholesterol, phospholipids and ketones and converts amino acids into glucose and synthesizes urea
5. Detoxifies drugs in bile, phagocytosis by Kupffer cells(breaks down RBC) |
|
|
What is phagocytosis by Kupffer cells?
|
Engulfs RBC's and breaks them down
|
|
|
|
What is the main function of the liver?
|
Filtering toxins
|
|
|
|
What is the agent used for hepatic imaging?
|
Tc99m Sulfur Colloid
|
|
|
|
How does the Tc99m Sulfur Colloid work in the liver scan?
(what does particle size have to do with it?) |
the particle size ranges from 10 -500nm, phagocytized by RES cells of the liver and spleen and bone marrow. larger particles by liver and spleen, smaller in bone marrow
|
|
|
|
How long is the uptake of Sulfur Colloid in the liver?
|
maximum concentration in the liver is 10-15 minutes
Where and how long does it take to be cleared? |
It is rapidly cleared by Kupffer cells 80-90% in 2.5 minutes, 5-10% by spleen and remainder by bone marrow
|
|
|
Explain the Liver-Spleen Scan technique
|
no pt prep, (No barium in system)
IV injection of 2-8 mCi Tc99m SC,(flow study for vascular flow of some tumors) Images at 15-20 min post injection counts 500k-1000k collimator: LEAP or LEHR SPECT with anterior and post static is preferred |
|
|
|
What is the concern when the splenic concentration is greater than 1:1?
If there is a problem, what additional images are taken? |
Greater uptake in spleen and bone marrow than liver means there is a liver problem,
What is this called when this happens? and what additional images are then taken? |
Colloid shift
add'l images would then be taken of shoulders and pelvis to see bone marrow. |
|
|
What are the planar images of the liver-spleen if SPECT is not done?
|
same as lung, all images, ant, post, laterals, RPO, LPO, RAO and LAO
|
|
|
|
Why is a flow study useful?
|
You can see vascular abnormalities like aneurisms, collateral flow, etc
|
|
|
|
What is a liver marker and what is it used for and where do you place it?
|
Shows size and position of liver, it is a 10 cm lead bar with holes spaced 1 cm apart. it is placed along the right costal margin (can also use cobalt rope or solder)
|
|
|
|
What is the best position to see the spleen?
|
Posterior view
|
|
|
|
What are breast shadow, rib impression and reidel's lobe have in common?
|
are variations on liver shape and size, all livers have variations
|
|
|
|
What are the indications for liver imaging?
|
Jaundice
elevated liver enzymes (alkaline phosphatase, LDH, GGT) Hepatitis Cirrhosis (scar tissue replaces good cells) Portal hypertension Cancer (metastatic lesions) |
Jumping Extra High Can Provide Clearance
|
|
|
What are we looking for in a liver-spleen scan?
|
determine size and shape of liver
function of RES cells detecting, monitoring masses differentiating hemangioma and nodular hyperplasia from other liver lesions identifying function splenic tissue and suspected asplenia |
Silly Red Men Love Strawberries
|
|
|
What is a liver neoplasm?
|
Cancerous growth that starts in the liver
|
|
|
|
What is focal nodular hyperplasia and how is it unique when compared to other pathologies of liver?
|
It is a benign tumor but unlike other lesions it appears hot (with SC) as it has a proliferation of normal hepatic tissue
|
|
|
|
What could be some sources of error on liver-spleen scan?
|
anatomical variations
respiratory motion colloid size breast attenuation |
CRAB
|
|
|
What is a liver Hemangioma?
|
It is a benign tumor or widening of a blood vessel in the liver that shows up on scan as the area has increased blood pool activity
Is it serous? |
no, up to 60% of people have them
|
|
|
With liver hemangioma when red blood cell tagging is used to visualize how long does it take to reach equilibrium?
|
30 to 60 minutes or more
|
|
|
|
What is the imaging protocol for imaging Liver Hemangioma?
|
Acquistion SPECT at 5 minutes and 2 hrs post injection of tagged RBC
IV injection of 20-25 mCi tagged RBC |
|
|
|
Why are planar and flow studies not done much any more for liver hemangioma studies?
|
SPECT is the preferred method now as lesions as small as 1 cm can be visualized as planar must be 3-4cm
better info and resolution with spect and takes same amount of time |
|
|
|
What are the invivo methods of tagging RBCs?
|
mix PYP with saline, stand 5 min
with draw 1-3 mL and inject wait 10-20 min and inject 20-30mCi Tc99m pertechnetate (modified you withdraw blood and mix with Tc99m pertechnetate mix for 5 min, then inject which is better? |
invivo 75% labeling efficiency
modified invivo 95% efficiency |
|
|
What is the other method for tagging red blood cells that involves multiple sticks that some say go against pharmacology rules?
|
Ultra Tag
it is 95% efficient |
|
|
|
What are the indications for a splenic scan?
|
Splenic scintigraphy is indicated in:
abdominal trauma detection of accesory spleens Polysplenia Asplenia Splenosis Splenomegaly |
TD PASS
|
|
|
What is the procedure for doing a splenic scan?
|
Tc99m SC - 5 mCi 3 sec flow from
posterior view Wait 5-10 (15-30, 30-120min –SNM) marker similar to liver scan. 300- 750k per static image, SPECT imaging can increase sensitivity. |
|
|
|
What is an alternative method that is not used much anymore for spleen?
|
Using denatured rbc with Cr51
goes right to spleen |
|
