Chest X Rays

Question 1

What’s a chest x ray

Answer 1

A CXR is produced by the electromagnetic beams passing through the thorax and exposing a photographic film, Image based on the anatomy of the patient blocking the transmission by varying degrees which results in an image caused by the degree of exposure of the photographic plate

Question 2

What’s radio-density

Answer 2

Less dense tissue such as air or air filled structures are referred to as radiolucent (black) more dense structures are referred to as radiopaque (white)

Question 3

What are the 4 basic radio densities

Answer 3

Gas= black e.g air filled lungs
Fat= grey e.g lipid tissue around muscle
Soft tissue= grey e.g heart, blood vessels
Bone of metal= white e.g ribs and sternum

Question 4

What are the types of CXR

Answer 4

Posteroanterior- most common, passes post to ant
Anteroposterior- commonly used for portable x rays
Lateral
Oblique

Question 5

How do you interpret a CXR

Answer 5

Easy to kiss significant abnormalities so use a systematic approach, preliminary check: name + date, projection, exposure, position, inspiration

Question 6

What questions to ask in a cxr

Answer 6

Who?what?when?why?how?

Question 7

What system to follow in a cxr

Answer 7

A- alignment, b-bones, c-cardiac, d-diaphragm, e-expansion, f-lung fields, g-gadgets(drips: drains and tubes)

Question 8

What to look for in alignment

Answer 8

Is this a straight film, look at prox end of clavicles in relation to spinous processes

Question 9

What to look for in bones

Answer 9

Are they all there, intact in a normal position, don’t just look at ribs

Question 10

What to look for in cardiac

Answer 10

Is there a clear Heart border, normal size, is there anything else to note in the mediastinum, evidence of shifting structures

Question 11

What to look for in diaphragm

Answer 11

Are both hemi diaphragm clearly visible? What about angles, cardiophrenic and castrophrenic

Question 12

What to look for in expansion

Answer 12

How well expanded is the chest, 10th rib posteriorly should bisect the right hemi diaphragms or mid clavicular line and rib the 6th rib anteriorly

Question 13

What to look for in fields

Answer 13

Are the lung fields clear? Any areas of density, increases or decreases, can you see a lung edge, fluid level?collapse and compnsolidayion you will see increased opacity, collapse you can see shifting of structures

Question 14

What to look for in gadgets

Answer 14

What drips, drains, tubes, limes and other gadgets are visible, are they in or around the patient

Question 15

What are some common abnormalities

Answer 15

Consolidation, atelctasis, collapse, pleural effusion, pneumothorax, pulmonary oedema

Question 16

What are other imaging that can be used

Answer 16

CT, MRI, U/S, CTPA

Question 17

How would you see consolidation on x ray

Answer 17

Lung tissue has become firm due to accumulated fluids, white grey shadow, no loss of volume, increased breath sounds ore decreased breath sounds with or without crackles, mainly due to pneumonia or lung infection

Question 18

How would you see atelectasis on a chest x ray

Answer 18

Airless state of lung, tissue (collapsed lung) can affect all or part of the lung, white grey shadow. With loss of volume and shifting of structures, only visible if collapse is significant, total collapse may pull mediastinum to affected side, quiet breath sounds p, fin end inspiratory crackles

Question 19

What would you see on cxr with pleural effusion

Answer 19

Excess fluid in pleural cavity, fluid white on CXR, small amount of fluid results in loss of Costco phrenic angle, large amount of fluid will push mediastinum to non affected side

Question 20

What would you see on cxr with pneumothorax

Answer 20

Air in pleural space secondary to rupture in pleural layer, lung squashed towards hilum, air in pleural space black, no lung markings, lung squashed appears as white density towards hilum, mediastinum pushed to unaffected side

Question 21

What would you expect to see on cxr of pulmonary oedema

Answer 21

Extra vascular water in lungs, bilaterally fleecy opacifies spreading from hila known as bats wing shadows, may also be enlarged, crackles in dependent regions, sometimes fine