CXR

Question 1

List the first steps needed to determine the quality of a CXR.

Answer 1

1. AP vs PA:
   i) PA is standard
   ii) AP at bedside (larger heart shadow, more lines, clavicle above apex of lung, lower diaphragm, horizontal ribs).
2. Exposure:
   i) Overexposed is too much x-ray, black.
   ii) Underexpose is too little x-ray, white.
   - Should see T/S vertebrae through mediastium up to T5/6.
3. Sufficient Inspiration:
   i) R diaphragm 9-11th rib posteriorly
   ii) L diaphragm 10-12th rib posteriorly
4. Patient position:
   i) clavicles should be equally close to vertebrae (rotated toward side w/ larger space).

Question 2

List features to look for regarding structures bordering and in the lung on a CXR.

Answer 2

1. Cardiothoracic index:
   i) heart to thorax ratio should be 1:2.
   ii) mediastinum should be 1:2, L:R
2. Costo and cardiophrenic angles (AKA silhouette signs):
   i) should be visible bilaterally
3. Trachea:
   i) should be inline w/ vertebrae
4. hilar markings
5. Vascular markings

Question 3

What would a COPD CXR look like?

Answer 3

i) flat diaphragm
ii) horizontal ribs
iii) pear shaped heart
iv) ++ rib count - hyperinflation

Question 4

What are the three direct and indirect signs of atelectasis on a CXR?

Answer 4

Direct:
i) displacement of fissures (toward)
ii) increased radiopacity
iii) vascular crowding
Indirect: 
i) displaced hilum (toward)
ii) raised diaphragm
iii) mediastinal shift (toward).