10. Imaging

Question 1

maximum normal diameter of caecum

Answer 1

9cm

Question 2

why is large bowel dilation alone uncommon?

Answer 2

ileocaecal valve allows backflow of pressure to small bowel

Question 3

typical patients who develop sigmoid volvulus

Answer 3

care home residents, psychotropic meds, slow bowel habits

Question 4

who develops caecal volvulus?

Answer 4

congenital rudimentary mesentery

caecum position abnormal

Question 5

where is contrast usually injected for GI CT?

Answer 5

anterior cubital fossa, wait 30 secs to reach aorta, further 30 secs to all GI tract and portal venous system, then renal

Question 6

benefit of barium meal/follow through vs endoscopy

Answer 6

see further into bowel

Question 7

first line for small bowel obstruction, renal colic

Answer 7

CT

Question 8

use of AXR in
-large bowel obstruction
-acute IBD
-renal colic

Answer 8

-volvulus
-toxic megacolon
-stone passed? (prevent unneeded surgery if so_)

Question 9

what forms haustra?

Answer 9

sacculations from contractions of outer longitudinal muscle of large bowel

Question 10

toxic megacolon appearance on AXR

Answer 10

fluffy due to mucosal islands
large

Question 11

why might free abdo gas under diaphragm be ok?

Answer 11

if patient had laparoscopy they day, they had co2 given to view stuff better

Question 12

CT features at T12

Answer 12

coeliac trunk
aortic hiatus of diaphragm,

Question 13

CT features at L1

Answer 13

-fundus of gallbladder
-pylorus of stomach
-neck of oancreas
-SMA
-L kidney hilum above
-R kidney hilum below

Question 14

CT features at L3

Answer 14

umbilicus
IMA

Question 15

CT features at L4

Answer 15

iliac crest
abdo aorta bifurcation to common iliacs

Question 16

where is IVC compared to liver at L3?

Answer 16

more distinct

Question 17

cool thing CT angiography can do

Answer 17

3D reconstruction