cxr

Question 1

List the steps of going through an xray

Answer 1

1. Confirm details
2. Asses Image quality (RIPE)
3. CXR Interpretation (ABCDE)

Question 2

What does RIPE stand for?

Answer 2

Rotation
Inspiration
Projection
Exposure

Question 3

What does ABCDE stand for?

Answer 3

Airway
Breathing
Cardiac
Diaphragm
Everything else

Question 4

How do you asses rotation?

Answer 4

The medial aspect of each clavicle should be equidistant from the spinous processes

The spinous processes should also be in vertically orientated against the vertebral bodies

Question 5

How do you asses inspiration?

Answer 5

5-6 anterior ribs
The lung apices
Both costophrenic angles
Lateral rib edges should be visible

Question 6

How do you asses projection?

Answer 6

AP vs PA film

Tip- if there is no label, then assume it’s a PA. Also, if the scapulae are not projected within the chest, it’s PA.

Question 7

How do you asses exposure?

Answer 7

Left hemidiaphragm visible to the spine and vertebrae visible behind heart

Question 8

List the things you should interpret for AIRWAYS

Answer 8

Trachea
Carina and Bronchi
Hilar structures

Question 9

How do you asses the trachea?

Answer 9

The trachea is normally located centrally or just slightly off to the right
If the trachea is deviated, look for anything that could be pushing or pulling at the trachea.
Also inspect for any paratracheal masses/lymphadenopathy

Question 10

What do abnormal tracheal deviation findings mean?

Answer 10

Pushing of trachea – e.g. large pleural effusion / tension pneumothorax

Pulling of trachea – e.g. consolidation with lobar collapse

Rotation of the patient can give the appearance of a deviated trachea, so as mentioned above, check the clavicles to rule out rotation as the cause.

Question 11

How do you asses the carina and bronchi?

Answer 11

The carina is located at the point at which the trachea divides into the left and right main bronchus.

On a good quality CXR this division should be visible and is an important landmark when assessing nasogastric tube placement, as the NG tube should bisect the carina if it is correctly placed

Question 12

Which bronchus is wider?

Answer 12

The right main bronchus is generally wider, shorter and more vertical than the left main bronchus. As a result it is more common for inhaled foreign objects to become lodged here (as the route is more direct).

Question 13

How do you asses hilar structures?

Answer 13

The hilar consist of the main pulmonary vasculature and the major bronchi.

The hilar are usually the same size, so asymmetry should raise suspicion of pathology

Question 14

What do bilaterally symmetrical enlarged hila mean?

Answer 14

Associated with sarcoidosis.

Question 15

What do unilaterally asymmetrical enlarged hila mean?

Answer 15

Underlying malignancy

Question 16

List the things you need to asses BREATHING

Answer 16

Lungs

Pleura

Question 17

How do you asses the lungs?

Answer 17

Inspect the lungs:

When looking at a CXR we divide each of the lungs into 3 zones, each occupying 1/3 of the height of the lung.

Question 18

What does shadowing mean?

Answer 18

Increased airspace shadowing in a given area of the lung field may suggest pathology (e.g. consolidation / malignant lesion).

Question 19

What does absence of lung markings mean?

Answer 19

Suspect pneumothorax

Question 20

How do you asses the pleura?

Answer 20

The pleura are not normally visible in healthy individuals, unless there is an abnormality such as pleural thickening.

Inspect the borders of each of the lungs to ensure lung markings extend all the way to the edges of the lung fields

Fluid (hydrothorax) or blood (haemothorax) can also accumulate in the pleural space, causing an area of increased opacity or a combination of both a pneumothorax and fluid

Question 21

List the things you should asses for CARDIAC

Answer 21

Asses heart size

Asses heart borders

Question 22

How do you asses heart size

Answer 22

In a healthy individual the heart should occupy no more than 50% of the thoracic width (e.g. a cardiothoracic ratio of <0.5).

This rule only applies to PA chest x-rays (as AP films exaggerate heart size), so you should not draw any conclusions about heart size from an AP film.

Question 23

List a few reasons that can cause cardiomegaly

Answer 23

Cardiomegaly can occur for a wide variety of reasons including valvular disease, cardiomyopathy, pulmonary hypertension and pericardial effusion.

Question 24

How do you asses heart borders?

Answer 24

The right atrium makes up most of the right heart border.

The left ventricle makes up most of the left heart border.

Question 25

What does loss of definition of heart borders indicate?

Answer 25

Loss of definition of the right heart border is associated with right middle lobe consolidation Loss of definition of the left heart border is associated with lingular consolidation

Question 26

List the things you need to look at to asses the DIAPHRAGM

Answer 26

Diaphragm | Costophrenic angles

Question 27

How do you asses the diaphragm?

Answer 27

The right hemi-diaphragm is in most cases higher than the left in healthy individuals (as a result of the underlying liver). The stomach underlies the left hemi-diaphragm and is best identified by the gastric bubble located within it. The diaphragm should be indistinguishable from the underlying liver in healthy individuals on an erect CXR

Question 28

What does it mean when you can distinguish the liver from the diaphragm?

Answer 28

PNEUMOPERITONEUM - free gas is present (often as a result of bowel perforation), air accumulates under the diaphragm causing it to lift and become visibly separate from the liver

Question 29

Which (niche) condition can give the false appearance of free air under the diaphgram?

Answer 29

Chilaiditi syndrome: Which involves the colon becoming positioned between the liver and the diaphragm resulting in the appearance of free gas under the diaphragm (because the bowel wall and diaphragm become indistinguishable due to their proximity)

Question 30

How do you asses costophrenic angles?

Answer 30

In a healthy individual the costo-phrenic angles should be clearly visible on a normal CXR as a well defined acute angle.

Question 31

What does costophrenic blunting indicate?

Answer 31

Can suggest the presence of fluid or consolidation in the area. Costophrenic blunting can also occur secondary to lung hyperinflation (seen in diseases such as COPD) as a result of diaphragmatic flattening and subsequent loss of the acute angle.

Question 32

List the things you asses at EVERYTHING ELSE

Answer 32

Mediastinal contours Bones Soft tissues Tubes/valves/pacemakers/lines

Question 33

How do you asses mediastinal contours? (2 things)

Answer 33

Aortic knuckle | Aorto-pulmonary window

Question 34

How do you asses aortic knuckle?

Answer 34

Left lateral edge of the aorta as it arches back over the left main bronchus. Loss of definition of the aortic knuckles contours can be caused by an aneurysm.

Question 35

How do you asses the aorto-pulmonary window?

Answer 35

The aorto-pulmonary window is a space located between the arch of the aorta and the pulmonary arteries. This space can be lost as a result of mediastinal lymphadenopathy (e.g. malignancy).

Question 36

How do you asses bones?

Answer 36

Inspect the visible skeletal structures looking for any abnormalities (e.g. fractures / lytic lesions).

Question 37

How do you asses soft tissues?

Answer 37

Inspect the soft tissues for any obvious abnormalities (e.g. large haematoma).

Question 38

How do you asses tubes/valves/ pacemakers/lines?

Answer 38

Tubes – nasogastric tubes are something you’ll often be asked to assess on a chest x-ray to confirm it is safe for feeding Lines (e.g. central line / ECG cables). Artificial valves (e.g. aortic valve replacement). Pacemaker (often located below the left clavicle).

Question 39

What are the review areas?

Answer 39

Lastly, before completing your assessment, always ensure you’ve looked at the ‘Review areas’ which are: ``` Lung apices Retrocardiac Behind the diaphragm Peripheral lungs Hilar ``` This ensures you’ve comprehensively assessed the x-ray and minimises the risk of missing subtle pathology (e.g. a small nodule).