Interpretation of Normal Chest X-rays

Question 1

What percentage of Chest X-rays are of all plain films?

Answer 1

30%

Question 2

What are the indications for chest X-rays?

Answer 2

• Acute deterioration in SOB
• Acute chest pain
• Suspected malignancy
• Pneumonia
• Pleural disease (mesothelioma)
• Peritonitis (erect for at least 10 mins pre image)
• Chronic lung disease
• Following invasive procedure e.g. central line, chest drain

Question 3

What are the two most common chest radiographs?

Answer 3

1. Posteroanterior

2. Anteroposterior

Question 4

What is more common over-exposed (hard) or under-exposed (soft)?

Answer 4

Under-exposed

Question 5

How do you make sure the patient has been orientated correctly when taking the x-ray?

Answer 5

The ends of the clavicles should be equidistant from the midline. The midline is determined by the spinous process’ of the vertebrae.

Question 6

What can too black or black in the wrong place indicate?

Answer 6

• Air

- Loss of tissue density

Question 7

What can too white or white in the wrong place indicate?

Answer 7

• Fluid

- Increased tissue e.g lymphadenopathy

Question 8

What can very bright white or very radio opaque indicate?

Answer 8

Medical hardware (e.g Pacemaker, ETT, NG tube, sternal wiring, prosthetic heart valves, CVP line, chest drain)

Question 9

What does the ABCDEFGH approach stand for?

Answer 9

• Airway
• Breathing
• CArdiac (heart)
• Diaphragm
• External structures and equipment
• Fat and soft tissue
• Great vessels
• Hidden areas

Question 10

What should you think about when assessing the airway (trachea)?

Answer 10

• Is it central?

- Carina at T4

Question 11

What bronchus is shorter wider and more vertical?

Answer 11

The right main bronchus

Question 12

What should you look for in Breathing (the lungs)?

Answer 12

• Is the patient at maximal inspiration? - this is checked by looking if the anterior 6th rib is crossing the dome of the right hemi-diaphragm
• Under-expansion (pain?)
• Over-expansion (Lung pathology COPD?)

Question 13

If your describing an abnormality on a chest x-ray what word would you use to describe the area in which it falls?

Answer 13

Upper, Middle or Lower Zone

Question 14

How big should the heart be in relation to the chest?

Answer 14

<50% of the diameter of the chest

Question 15

Where should the heart be visible from?

Answer 15

1/3 should be visible to the right of the sternum (2/3 to the left)

Question 16

What should you look for when looking at the x-ray of the diaphragm?

Answer 16

• The right hemi-diaphragm is usually one rib higher than the left
• Identify the gastric bubble
• Look below the right (and the left) hemi-diaphragm for air from a ruptured hollow abdominal viscus

Question 17

What should you look for when looking for external structures?

Answer 17

• Bones

- Medical devices

Question 18

What should you look for in fat and soft tissues?

Answer 18

• Breast shadows

- Signs of surgical emphysema

Question 19

What should you look for in the great vessels?

Answer 19

• The aortic arch, pulmonary arteries and veins of the mediastinum
• Look for calcium deposits in the elderly amongst vessles
• Left hilum should be higher up than right hilum
• Enlargement of the hilum could indicate lymphadenopathy

Question 20

What should you look for when looking at hidden areas?

Answer 20

• Neck
• Apices
• Mediastinum: widening, adenopathy, mediastinal lymph nodes
• Behind the heart
• Costophrenic angle
• Behind/below diaphragm
• Soft tissues
• Bone

Question 21

What is the ‘gold standard’ x-ray?

Answer 21

Erect PA film