Radiology

Question 1

What is a radiograph?

Answer 1

An electromagnetic wave of high energy and very short wavelength, which is able to pass through many materials opaque to light.

A photographic or digital image of the internal composition of the body, produced by X-Rays being passed through the body part and being absorbed to different degrees by different tissues.

This is displayed as levels of contrast on a grey scale (black to white)

Question 2

What is the dose of X-Rays in a radiograph?

Answer 2

0.02 mSv - Very minimal so unlikely to get anything from it.

Question 3

What is a standard projection of X-Ray?

Answer 3

PA - posterior to anterior

Question 4

Why is PA better than AP?

Answer 4

Cant comment on heart being enlarged on AP film as there is a degree of magnification.

Question 5

When looking at an X-Ray, What do we need to see?

Answer 5

1st rib
Lateral margins of ribs
Costophrenic angle (inferio)

Question 6

How can we tell if the chest is rotated?

Answer 6

Look at the alignment of the spinous process and clavicles -medial ends

Question 7

Why is it important that a chest X-Ray isn’t rotated?

Answer 7

Because many pathologies pull the trachea to the side and, if a chest X-Ray isn’t central. the trachea can look off centre.

Question 8

If an X-Ray is taken during the inspiratory phase, what do we expect to see?

Answer 8

5-7 anterior ribs at MCL.

But, if they have incomplete inspiration, it looks like they have a big heart and increased lung markings.

Exaggerated expansion occurs in obstructed airway disease.

Flattened diaphragm = sign of emphysema.

Question 9

How do we know if there is adequate penetration?

Answer 9

Vertebrae just visible through the heart

Complete left hemidiaphragm visible.

Question 10

What is an artefact?

Answer 10

External / iatrogenic material which obstructs view.

• Clothes - buttons
• Hair
• Surgical/ vascular lines
• Pacemaker

Question 11

What is the hilar points?

Answer 11

This is formed by the outer margins of the superior pulmonary vein and the descending pulmonary artery as they cross each other.

The left should always be higher or the same level as the right or it implies pathology.

Question 12

How do you break down the lungs to describe where pathologies are?

Answer 12

Upper, middle and lower zones.

Also into right and left.

Question 13

What are the costophrenic recess / angles?

Answer 13

These are the spaces at the bottoms of the lungs between them and diaphragm (on outside). If they aren’t there, we worry about pathology