imaging Flashcards
liver, biliary and pancreatic disease= ultrasound benefits and uses
noninvasive safe and cheap jaundiced patient hepatomegaly or splenomegaly gallstones focal liver disease (lesions greater than 1 cm) general parenchymal disease portal and hepatic vein patency lymph node enlargement
colour doppler ultrasound
demonstrate vascularity within the lesion and the direction of portal vein blood flow
ultrasound contrast agents (liver)
production of micro bubbles can detect blood flow allows the detection of vascularity and abnormal circulation within the liver nodules (specific diagnosis of hepatocellular carcinoma)
hepatic stiffness (transient elastography)
volcity of the transducer beam correlates with hepatic stiffness increased stiffness is associated with worsening liver fibrosis (80% sensitivity and specificity compared to biopsy) limited to not detecting cirrhosis, and not in obese or with ascites
useful in staging of small potentionally opera table pancreatic tumours and bile duct imaging. used to place transmural tubes to drain pancreatic and peripancreatic fluid collections
endoscopic ultrasound
CT use in liver pancreas and biliary tree
Contrast- good for showing the arterial and venous vasculature
lesions and vascular supply of the lesions.
guidance for biopsy and also can detect calcification and used with obese patients
MRI in Liver, BD, Pancreas
focal liver disease
angiography and venography of splanchnic circulation,
Magnetic resonance cholangiopancreatography
This has replaced diagnostic endoscopic retrograde cholangiopancreatography. It can visualise the biliary ducts dn pancreatic ducts with high quality imaging.
Chest X ray of the abdomen
rarely requested
gallstones (but only if they contain more than 10% calcium)
any sort of calcification they will show
radionucleotide imaging
IODIDA scan used for acute cholecystitis
ERCP
endoscopic retrograde cholangiopancreatography
technique outlines the biliary and pancreatic ducts.
Endoscope into he second part of the duodenum and cannulation of the ampulla. contrast is then injected and the patient is screened radiologically. So this is reserved for therapeutic measures such as: common bile duct stones (sphinctotomy complication acute pancreatitis)
biliary drain or stent
brachytherapy treatment for cholangiocarcinoma
percutaneous transhepatic cholangiography
this goes through the skin into the liver and then contrast is inserted and then the biliary anatomy is visualised.
liver biopsy
indications: liver disease hepatomegaly jaundice severe cirrhosis tumours primary and secondary CI: patient refused, prolonged PT greater than 3 sec increased bleeding risk.
Rheumatology imaging X-rays
joint space narrowing, erosions in rheumatoid, calcification in the soft tissue, osteopenia (decreased bone density) or increased bone density (osteosclerosis).
- acute back pain if it is recurrent and persistent associated with neurological signs or if worse at night and associated with fever or night sweats.
- useful in baseline but not diagnostic in inflammatory arthritis
Rheum US
detecting active synovitis in inflammatory arthritis
guide local injections
periarticular structures and soft tissue swellings
DXA scan
low radiation dose scan for bone density and screening and monitoring for osteoporosis.
MRI in rheum
shows bone changes and intra-articular structures in high quality detail
bone marrow oedema
articular and periarticular disease more sensitive
CT in rheum
just going to show calcification little usefulness.
arthroscopy in rheum
visualisation of the joints particularly the knee and the shoulder joint
repair and trimming of medic=scal tears and lose body removal.
PET scan in rheum
Positron emission tomography
uses radionuclides which decay emitting positrons
F- fluorodeoyglucose indicates areas of increased glucose metabolism.
looking for tumours and large vessel vasculitis .
renal imaging plain X ray
renal calcification or radiodense calculi in the kidneys renal pelvis line of the ureters or bladder.