US Flashcards
Vessel anatomy - inner to most outward?
Tunica interna
(connective tissue) inbetween these two
Tunica Media
Tunica externa
AAA Symptoms? Measurement on US? Additional images to take? Causes?
SOB, back pain, flank pain, N/V, Abdo pain
>3cm - thrombus on the lumen
•Aneurysm measured in transverse and longitudinal planes (depth and width)
•Assess for clot or thrombus
•Longitudinal images of iliac vessels from bifurcation to the most distal segment
Transvers scans of iliacs below the bifurcation. (need to determine where it is).
Dissecting aneurysm
Aortic dissection is a tear in the aortic intima that enables blood to force its way between the other layers of the vessel wall, forming an intimal flap that divides the aorta into a true and false lumen.
What are the three classifications of dissecting aneurysm
- Type 1 &2: involve ascending aorta and arch.
* Typer 3: descending aorta at a level inferior to left subclavian artery
what is cylinder tangent effect?
Your plane of the beam enters the aorta at a tangent and falsely reduced AP diameter is resulted
What makes the portal conflunce?
where the portal vein and splenic vein meet
Where is the GDA and CBD located?
Gastroduodenal artery is superior in the head of the pancreas
Common bile duct is inferior in the head of pancreas
why does the pancreas become more echogenic in older patients?
Fatty infiltration
what happens to the GB when we eat?
When we eat - stomach stimulates the GB to excrete bile into the duodenum and stimulate the pancreas to excrete digestive enzymes
Excocrine cells (97%) - what do they do? How does it work
Pancreatic duct conveys pancreatic digestive secretions to the duodenum
Pancreatic duct empties into the duodenum via the major papilla after meging with the CBD in the ampulla
What are the three ezymes that acinar cells secrete and what do they help with?
Amylase, lipase, peptidase
Digestion
Endocrine cells (3%) What are they responsible for?
Insulin productions
What are the insulin hormones called in the pancreas?
Islets of langerhan - found in clusters
What are the islets of langerhan hormones cells divided into?
Alpha- glucagon, stop the levels from dropping to low
Beta- Insulin, controls blood glucose levels - help storage of it
Gamma - pancreatic polypeptide - regulates pancreatic secretion
Delta - somatostatin - inhibits the secretion of pancreatic hormones including glucagon and insulin
Acute pancreatitis
Acute inflammaotry process of the pancreas
Caused by destruction by own digestive enzymes - occue when digestive enxymes become activated while still in the pacreas - causing inflammation
Causes: gallstone in the ampulla of vater, alcohol
Signs and symptoms: epigastric pain, nausea, vomitting, pain
ultrasound appearance pancreatic periampullary neoplasm
ill defined margins alter in gland controur solid hypoechoic lesion ductal dilation double duct sign pacreatic duct and CBD dilation
Intraductal papillary mucinous neoplasm (arise from main pancreatic duct and its side branches) US appearance
Pancreatic duct dilation
formation of cysts
Mucinous cystic neoplasms (arise from peripheral ducts) US appearance
in body/tail
round of ovoid-shaped unilocular or multilocular cysts
fine echoes, thick walkks, calcifications on the wall of sepata.
Parietal nodules and papillary vegetations
Serous cystadenoma (benign lesion/ tiny cysts) US appearance
Head
microcystic appearance, lobulated margins internal septa arrange radially and converging on the central scar
name two neuroendocrine tumours andultrasound appearance
Gstrinoma (focal isoechoic mass, single or multiple) - produce large amounts of hormone gastrin - stimulates excess production of excess gastric acid from the stomach - can lead to zollinger ellison syndrome
Insulinoma (homogneously hypoechoic, round in shape with distinct margins - make extra insulin more than your body can use. Causes hypogylcemia or low blood sugar (can go into coma).
What is zollinger-ellison syndrome
rare digestive disorder that results in too much gastric acid. causes peptic ulcers in your stomach and intestine
Choledochal cyst
congenital dilations of the bile ducts
most common is - diffuse dilation of the extrahepatic bile duct
Caroli disease
congenital disease of the intrahepatic biliary tree. biliary tree does not form. Causes biliary stasis
Appearance: dilated ducts with sacculation
type one: simple
typer two: congenital hepatic fibrosis also associated with cystic renal disease
Choledocholothiasis
stones made of calcium bilirubinate.
Primary: within the ducts - distal duct or at the ampulla of vater.
Secondary: Migration of stones from the gallbladder into the CBD (most common)
Highly echogenic
posterior shadowing
Cholangitis
Biliary tree infections
Biliary obstruction most common causes.
Dilation of biliary tree
Choledoc /sludge
Bile wall thickening
CBD greater than 6
three types of cholethiasis stones?
Cholesterol supersaturation
Excess bilirubin
Ultrasound appearance of Cholelithiasis
Highly echogenic
posterior acoustic enhancement
May demonstrate twinkling artefact
Gallbladder sludge
sludge forms when bile remain in the GB for too long.
Low level echoes within GB with no acoustic shadowing
Mobile sludge
Lack of internal vascularity.
Sludge has same echotecture as the liver, camouflaging the GB called hepatisation.
Acute /chronic cholecystitis
Acute -caused by gallstones in more than 90% impaction of stones in the cystic duct or GB neck
Chronic - reoccuring events. swelling and irritation of the GB - advanced stages will have no positive murphy sign and hyperemia
Thickened GB >3mm
Distension of GB lumen 4cm
High echogenic gallstones - posterior acoustic enhancement
impacted stone in cystic ducts of GB neck
Pericholecystic fluid collection
hyperemic GB on doppler
Adenomyomastosis (GB)
benign condition caused by hyperplastic changes. Causes over growth of mucosa,, thickening of the muscular wall, formation of intramural diverticula (rokitansky-ascoff)
Focal or diffuse
tiny echogenic foci in the GB with comet tail artefact
Pneumobilia
Air within the biliary tree
from intervention
Bright echogenic linear structure following the portal triads
Posterior dirty shadowing, reverberations and ring down artefact
Biliary atresia
Blockage in the ducts - congenital - occurs when bile ducts inside or outside the liver do not develop normally.
Jaundice, dark urine, >bilirubun, jaundice
Echogenic fibrous tissue anterior to the portal triangular cord sign
GB ghost triad - <19mm in length, irregular or lobular contour, lack of smooth/complete echogenic mucosal lining with indistinct wall
