indications for a KUB
i. Bowel gas pattern
ii. Foreign bodies (especially things up the butt)
iii. Calcifications,
iv. Tube placement
KUB stands for
kidney abdomen bladder
need to see the entire abdomen and the diaphragm
when would you get a KUB ubright and CXR
is you suspect a bowel obstruction
if you suspect a perf
1. Upright film –>look for air-fluid levels &/or free air
if you are looking for air fluid levels with images would you want
upright horizontal to the floor or lying down but the beam needs to be placed at the side
this is a sign of obstruction
what muscle should be visible bilaterally in a KUB
psoas
Has valvulae conniventes
small or large bowl?
small
Has haustra
small or large bowl?
large bowel
characteristics of haustra
- Widely spaced
diameter and wall thickness of large bowel
< 5 cm diameter
< 3 mm wall thickness
how much air do we usually see in the small bowel
Little air in lumen (2-3 loops max)
diameter and wall thickness of small bowel
< 2.5 cm diameter
< 3 mm wall thickness
characteristics of valvulae conniventes
Traverse the entire lumen
-Spaced closer together compared to haustra
air fluid levels in the colon normal or nah?
NO
no air fluid levels in the colon NOT NORMAL
when the bowel stops progressing it is known as a
ilieus
can you have air in the rectum with a small bowle obstruction?
yes~
what is the difference between a complete and partial small bowel obstruction
Complete –>no air distal to obstruction (sigmoid, rectum)
- Partial —> some air distal to obstruction
what is the relationship between obstruction proximity in the small bowel and loops of air seen on film
More proximal the obstruction, the fewer bowel loops are seen
what would you expect to see on a supine (KUB)
of a small bowl obstruction
Dilated loops, centrally located
- “Stack of coins,”
“bent finger sign”
what would you expect to see on a upright film of a pt with a small bowel obstruction
Air-fluid levels, may look like a “step-ladder”
- “String of pearls” (air trapped in successive valvulae conniventes)
types of large bowel obstructions
Can be mechanical (mass, twist)
- Can be from fecal impaction or inflammation
LBO
Volvulus
special type of LBO where it twists like a Jesus fish
Coffee bean sign
. Sigmoid volvulus
and axis of bean points to LLQ)
. Cecal volvulus
feet of embryo point to RLQ