CT Application 4 Abdominopelvic Flashcards
where is quadrate lobe
between gallbladder and round ligament
where is caudate lobe
between IVC & ligamentum venosum
what separates left and right lobe
interlobar fissure
largest liver lobe
right lobe
smallest liver lobe
caudate lobe
since liver tissues lack typical capillary network, what do they have instead
blood-filled sinusoids surrounding hepatic cells
what happens during portavenous phase CT
Right + middle + left hepatic veins filled with contrast-mixed blood emptying into IVC
what divides liver vertically
hepatic veins & falciform ligament
what divides liver horizontally
hepatic portal veins
cirrhosis indicator
Jagged outline of liver
biliary system includes
- gallbladder
- intraheptic bile duct
- common bile duct
- pancreatic duct
hemangioma
benign vascular tumor
3 constrictions of KUB
- ureteropelvic junction
- pelvic inlet
- bladder entrance
In CT Abdominal imaging, what does ‘contrast enhancement’ refer to?
Improve visualization of structures of similar density
fasting duration for oral contrast
2 - 6 hrs
CT triphasic liver process
non-contrast > arterial > portavenous > delayed
when does arterial phase occur
20 - 40s
when does portavenous phase occur
80 - 90s
slice thickness & interval for CT abdomen pelvis
3 - 5 mm
recon window for CT abdomen pelvis
mediastinum & lung base
scan region for CT abdomen pelvis
lung bases > past rectum / upper thigh (male)
non-contrast CT abdomen pelvis indication
renal / colic stone
early arterial phase timing
20 - 30s post IV injection / bolus tracking
importance of early arterial phase
- studying arterial vessels
- aortic dissection
- arterial bleeding
late arterial phase timing
30 - 40s post IV injection / 20s after bolus
late arterial phase enhances view of ___
- hypervascular lesion
- stomach + bowel
- pancreas parenchyma
- spleen
- kidney cortex
portavenous phase timing
80 - 90s post IV injection / 50 - 60s after bolus tracking
portavenous phase detects ___
- hypovascular liver lesion
- cysts
- abscess
- metastasis
- hepatic parenchyma
delayed phase timing
4 - 7 mins post injection
delayed phase enhances viewing of ___
- fibrotic lesion
- KUB collection
- liver metastasis
- TCC
TCC
transitional cell carcinoma
In liver triphasic contrast, which phase will determine whether the lesion in the liver is benign or malignant?
delayed phase
Which of the following is NOT a common indication for CT MSK imaging?
A) spinal cord injury
B) joint dislocation
C) muscle strain
D) bone tumors
C) muscle strain
What is the typical slice thickness used for CT imaging of the small extremities?
0.5mm
MAR
metal artifact reduction
DSI
dual source imaging
what does DSI allow for
use of high keV monochromatic images to reduce beam hardening effects
Which of the following is/are benefit(s) of using CT for musculoskeletal imaging? Select all that apply.
A) high spatial res
B) image complex #
C) superior soft tissue contrast
D) faster scan times than MRI
A, B, D
where does liver receive blood from
hepatic portal vein mainly and hepatic artery
cirrhosis features
jagged edge liver (surface nodularity), hypertrophy, parenchymal heterogeneity, ascites
cysts/lesion features
hypodense bubblesf
fatty liver features
hypodense liver
gallbladder stone features
diamonds in gallbladder
dilatation features
“black vessels” seen
hemangioma features
“sun” shape seen
HU of simple cyst
<20HU
complex cyst HU
80HU
what indicates 1st part of duodenum
duodenal bulb
how to differentiate between jejunum & ileum
ileum hyperdenser than jejunum and closer to right side
what oral contrast used to distend GI tract and show intestinal lumen
diluted iodinated CM, barium sulphate, water
CT contrast phases of kidneys
corticomedullary = 30-40s
nephrogram = 80 - 120s
excretory 3 mins
small obstructions occur due to ___
adhesions, hernias, masses
inflammatory bowel disease sign
target sign made of serosa, submucosa, mucosa
volvulus sign
bird beaks at large bowels
how does HCC liver appear
arterial phase = hyperdense
portavenous = isodense
delay = hypodense
slice thickness of CT hip/pelvis
2-5mm
