Ch.3

Question 1

Iv contrast media and brain gray matter

Answer 1

•iodine raises the attenuation of normal brain gray matter thereby increasing contrast and CT visualization.

Question 2

CTA of the brain is used to identify

Answer 2

• aneurysm
• thrombosis
• stenosis

Question 3

Cerebral perfusion refers to

Answer 3

•the level of blood flow throughout brain tissue

Question 4

Soft tissue neck and iodine to evaluate

Answer 4

• mass
• salivary gland
• lymph nodes
• tumors

Question 5

CTA of the neck is to evaluate

Answer 5

• carotids
• stenosis
• occlusion
• aneurysm
• trauma

Question 6

Pulmonary embolism occurs

Answer 6

• when a thrombus (blood clot) breaks free usually from a lower extremity and migrates to the pulmonary artery
• this it becomes blocked causing reduced blood flow to the lung tissue

Question 7

CTA chest injecting saline reduces

Answer 7

artifact from from the dense contrast in the superior vena cava

Question 8

Aortic dissection

Answer 8

•occurs when an inner layer of the aorta tears and a false lumen is created

Question 9

Hypovascular

Answer 9

•if the contrast is lower in density than the surrounding organ

Question 10

Hypervascular

Answer 10

•if the tumor has is higher in density then the surrounded organs

Question 11

The most common malignant hepatic neoplasm are

Answer 11

• metastases

* usually appear hypodense (less dense than the structures surrounding them)

Question 12

Hemangioma

Answer 12

• benign neoplasm of the liver

* commonly found post contrast imaging

Question 13

Hepatocellular carcinoma

Answer 13

• malignant neoplasms of the liver
• appears hypodense on non contrast scans
• hypervascular/hyperdense during arterial phase

Question 14

Three phases of the hepatic contrast enhancement

Answer 14

• arterial phase
• portal/hepatic (venous phase)
• equilibrium phase

Question 15

Arterial phase (liver)

Answer 15

• 25-35 sec. scan after contrast
• hypervascular tumors or tumors supplied by the hepatic artery are enhanced
• the hepatic arterial supply is well opacified

Question 16

Liver has dual blood supply from

Answer 16

• 75% from portal vein

* 25% hepatic artery

Question 17

Portal venous phase (liver)

Answer 17

• period of peak hepatic parenchymal enhancement
• contrast redistributes from the blood into extravascular space
• 60-80 sec scan delay
• hypovascular are seen

Question 18

Equilibrium phase

Answer 18

•2-3 min delay

Question 19

Hepatic early arterial phase is to visualize

Answer 19

• 15-20 sec

* assessment of the hepatic arterial supply

Question 20

Hepatic arterial phase assessment

Answer 20

• 25-35 sec

* for optimal visualization of hypervascular hepatic lesion such as hemangioma

Question 21

Hepatic portal venous phase assessment

Answer 21

• 60-70 sec

* for evaluation of hepatic parenchyma and hypovascular lesions such as hepatic metastasis

Question 22

Spleen arterial phase

Answer 22

•demonstrates a heterogeneous enhancement pattern

Question 23

Preferred timing phase for spleen

Answer 23

• portal venous phase 60-70 seconds

* homogeneous pattern of enhancement

Question 24

Kidney corticomedullary phase

Answer 24

• late arterial phase 30-40 sec

* enhancement of the Renal cortex and renal veins

Question 25

Kidney nephrographic phase

Answer 25

* 70-90 sec delay * optimal vision of parenchyma lesions * hepatic enhancement

Question 26

Kidney excretory phase

Answer 26

* 3min delay | * contrast has been excreted into renal calyces enhancing the renal pelvis, ureters/bladder

Question 27

Optimal phase for GI tract

Answer 27

* portal venous phase | * optimal gastric and intestinal wall enhancement

Question 28

The duodenum bulb connects to the

Answer 28

•stomachs pyloric sphincter

Question 29

The ileum leads to

Answer 29

•the large intestine at the ileocecal valve