Radiology IV - Abdomen Flashcards
1
Q
Abdominal radiography indications
A
- Limited use of abdominal x-rays compared to CXR
- Bowel obstruction vs ileus
- Constipation
- GI perforation
- Renal calculus
- Foreign body/ ingestion
2
Q
AXR anatomy
A
- Lung bases
- Heart size
- Free air/ portal venous gas
- Solid organs
- Bowel gas pattern
- Abnormal calcifications
- Bones
3
Q
Bowel obstruction
A
- Small bowel obstruction (scarring, adhesions) = most common
- Large bowel obstruction or gastric outlet obstruction (tumors) = less common
4
Q
Free air
A
- # 1 concern = bowel perforation
- surgical emergency
5
Q
Urethral calculus (aka. kidney stone)
A
- Size measurements are important bc stones >5 mm are unlikely to pass on their own
- Non-obstructing calculi are not of ACUTE concern
6
Q
Cholecystitis
A
- Underlying pathophysiology related to obstructing stone in neck –> inflammation
- u/s is 1st dx imaging test
7
Q
AXR advantages
A
- Quick & cheap
- Good eval of bowel gas pattern
8
Q
AXR disadvantages
A
- Radiation
- Limited differentiation & specificity
9
Q
X-ray densities
A
From least to most dense:
- Air/lung
- Fat
- Soft tissue density
- Bone/calcification
- Metal
10
Q
Bowel size
A
3/6/9 rule
- Small bowel < 3 cm
- Large bowel <6 cm
- Cecum <9 cm
11
Q
Colitis ddx
A
- Infectious
- Inflammatory
- Ischemic
- Neoplastic
12
Q
What is inflammation on CT?
A
Fat stranding
13
Q
Acute appendicitis
A
- Obstruction of proximal appendiceal lumen –>
dilation, inflammation, & eventual perforation - Commonly w/ appendicolith
14
Q
Colon cancer
A
- Early stage may be occult on CT. More advanced lesions visible
- Colonoscopy is best
- Barium enema
15
Q
When should you order a non-contrast CT?
A
- Renal stone
- Abdominal pain & low GFR
