דימות

Question 1

the five denseties of x-ray

Answer 1

barium (metal, white)
bone
muscle
blood
fat
air (black)
(most to least)

Question 2

GI Fluoroscopy

Answer 2

Contrast:
Barium sulfate suspension
Telebrix (water soluble)

Administration: oral or rectal

Single contrast vs double contrast (with air, usually not SI)

Question 3

barium enema

Answer 3

could be fecal or polips, etc.

bowls need to be clean before exam

Question 4

Imaging Planes

Answer 4

axial-
rostral to coudal, like sausage

coronal-
left is right and right is left, we look at the body from frontal perspective

sagital-
awnterior poterior, we look at the body from lateral perspective

Question 5

Hounsfield units

Answer 5

Range -1000 to 1000
Metal = 1000
Water = 0 HU
Air = -1000
Soft tissue 50-70 HU
Fat = -10 , -20 HU

Question 6

CT window

Answer 6

computer manipulation of the shades of gray we see (no need for additional x-ray!)

Question 7

Triphasic CT

Answer 7

before contrast
after contrast -arteria
after contrast- veins
in tumors lighting from periphery to center

Question 8

ultrasound scale

Answer 8

Anechoic- black, air
Hyperechogenic- white in contrast to serounding tissue
Hypoechogenic- black in contrast to serounding tissue
isoechogenic- same contrast as serounding tissue

Question 9

ultrasound imaging

Answer 9

ideal for soft tissue, fluid spaces

unsutable for air spaces and boney structurs

Question 10

with which atom does MRI deal with?

Answer 10

hydrogen

When placed in a magnetic field, align either with or opposite to the direction of the field

Question 11

MRI contraindications?

Answer 11

Pacemakers
Metal shrapnel
Claustrophobia
Renal failure (contrast is problematic in those)

Question 12

Radiologic Approach to Abdominal Pain

Answer 12

CXR for free air under the diaphragm or lower lobe pneumonia

Supine and upright abdominal x-rays (empty GI)

Ultrasound, CT scan, IVP, barium enema, UGI, endoscopy and colonoscopy when indicated

Question 13

Types of abdominal pain

Answer 13

Colicky pain- distention of a hollow viscus, such as bowel

Somatic pain -inflammation of the parietal peritoneum – “בטן כירורגית”

Visceral pain-
inflammation of the visceral peritoneum and capsule of solid organs (hepatitis)

Question 14

Radiologic Approach to Abdominal Pain (locations)

Answer 14

RUQ/LUQ- ultrasound, Visceral organs

LLQ/RLQ- CT, air filled organs, Bowel pathologies

Question 15

Right Upper Quadrant findings

Answer 15

Gallbladder- most common (US)
Acute cholecystitis (gall wall thickening)
choledocholithiasis

Liver- distention of capsule (US)
hepatitis
liver abscess
metastasis
portal cein thrombosis

pancreas- (US, CT)
acurte pancreatitis (murky serrounding fat)

Stomach /duodenum (ENDOSCOPY)
Gastritis, PUD

Non abdominal causes (CXR)
RLL pneumonia

Question 16

Left Upper Quadrant findings

Answer 16

Spleen- most common (US)
Spelnomegaly (normal up to 13cm)
infarct
hemmorage

Stomach /duodenum (ENDOSCOPY)
Gastritis
PUD
gastric cancer

Non abdominal causes – LLL pneumonia (CXR)

Question 17

lower Q’s of abdomen findings

Answer 17

diverticulosis (CT)
pockets extending out from the colon caused by pressure exerted within by the contracting

appendicitis (CT,demonstrate better complications and alternative diagnoses, radiation / US, NPV is quite low at )
trapped feces
rough
over 6mm diameter

Colitis (CT)
wall thickening

Colon Cancer (CT, MRI superior for rectal Ca – defines sphincters
metastates

polyps (double contrast CT, virtual colonoscopy)

Question 18

Diverticulosis - complications

Answer 18

trapped feces (infection)

30-50% of massive lower GI bleeding caused by small blood vessel in diverticula

Perforation
abcess
peritonitis
fistula

Question 19

Approach to Abnormal LFTs

Answer 19

Obstructive

    Inside ducts (US, ERCP, MRCP)
Stones, polyp, tumor

    Outside ducts (US, CT)
Tumor (pancreas.ect. , inflammation)

Non obstructive
Evaluation of liver parenchyma
Liver masses
(CT, MRI)