Abnormal CXR

Question 1

Identify the main “things” to look at when looking at a CXR.

Answer 1

A Airway
B Breathing (i.e. lungs)
C Cardiac (heart)
D Diaphragm
E External Structures & Equipment
F Fat & soft tissue
G Great vessels
H Hidden areas

Question 2

What are possible abnormalities in the airway on a CXR?

Answer 2

• Endotracheal tube too close to the carina (i.e. needs to be withdrawn)
• Mediastinal shift (i.e. trachea moves to one side)
• Angle of the bronchi increased by pressure from enlarged lymph nodes (Sarcoid, Tumour) or by local tumour.

Question 3

What are possible pathologies which may lead to mediastinal shifts ?

Answer 3

Pathologies pushing mediastinum AWAY:

• Too black = tension pneumothorax
• Too white = massive pleural effusion (or any mass effect, i.e. effect of a growing mass that results in secondary pathological effects by pushing on or displacing surrounding tissue e.g. tumour)

Pathologies pulling mediastinum TOWARDS
-Too white = Atelectasis (=lobar collapse, i.e. something obstructing a main bronchus, no air can get into the lung, lung shrivels up and pulls mediastinum towards it), or pleural fibrosis, or pneumonectomy/lobectomy

Question 4

Give the CXR appearance of a pneumothorax.

Answer 4

• Black on one side
• Mediastinal shift away from blacker area
• Visceral pleural line, with no lung markings seen peripheral to this line (abnormal)

Question 5

What are possible causes of pneumothorax ?

Answer 5

Penetrating chest injury

Iatrogenic (e.g. dialysis central line)

Question 6

What signs of pneumothorax would you find upon clinical examination ?

Answer 6

• Inspection: Chest pain, diminished respiratory rate (and shortness of breath), possibly cyanosed
• Palpation: Limited expansion on the R inside of the pneumothorax
• Percussion: Hyper resonance
• Auscultation: Decreased breath sounds on the right

Question 7

What are possible abnormalities in breathing (i.e. lungs) on a CXR ?

Answer 7

1) Consolidation (i.e. opacification due to replacement of normal air space gas with fluid or solid material).
- Characteristic sign of consolidation is air bronchogram (i.e. large airways are spared so become visible (black) against the white background)

2) Atelectasis
Some opacification, mediastinal shift (TOWARDS) and a loss of V (dragging diaphragm/fissures superiorly)

3) Pleural effusion
Mediastinal shift AWAY, lower zone uniformly white (on one side or the other), concave upper border (meniscus), no evidence of air bronchograms

4) Asbestos Exposure
- Calcified plaque (not malignant itself) on pleural cavity
- Mesothelioma (present as pleural effusion, but with holly leaf opacification)

5) Pneumothorax
- Black on one side
- Mediastinal shift away from blacker area
- Visceral pleural line, with no lung markings seen peripheral to this line (abnormal)

Question 8

What are the clinical findinds of pneumonia ?

Answer 8

Inspection: 
Productive cough
Fever
Shortness of breath 
Tachycardia

Percussion: Dull to percussion over the left lower lung
Auscultation: breath sounds are harsh

Question 9

What are the main substances of consolidation ? What causes each ?

Answer 9

Pus - infection (pneumonia) 
Blood - Pulmonary haemorrhage
Fluid - Pulmonary oedema, drowned lung
Cells - Lung cancer
Protein - Alveolar proteinosis

Question 10

How do we know which lobe is affected by consolidation ?

Answer 10

On L side:

• L heart border clearly defined then LLL (opacification lower than that)
• If opacification directly adjacent to L heart margin, causing blurring of heart border then LUL (/lingula)

On R side:

• If opacification above horizontal fissure, RUL
• If opacification directly adjacent to R heart margin, causing blurring of heart border then RML
• If opacification lower than RUL and does not cause blurring of heart border, then RLL

Question 11

What might we be unsure of the location of the consolidation ?
What can we do to figure out which lobe is affected ?

Answer 11

Due to the presence of the oblique fissure on the R lung (so can have UL anteriorly but LL posteriorly)
By using a lateral X Ray

Question 12

Can we know the substance in a consolidation based on the CXR ?

Answer 12

No, but possibly have a guess using patient history

Question 13

Distinguish atelectasis from consolidation.

Answer 13

Consolidation involves opacification
Atelectasis involves some opacification, mediastinal shift (TOWARDS) and a loss of V (dragging diaphragm/fissures superiorly)

Question 14

What are the clinical findings of consolidation ?

Answer 14

• Dull to percussion
• Increased vocal resonance
• Bronchial breathing

Question 15

Define atelectasis. Which features of a CXR may hint at an atelectasis ?

Answer 15

Reduction in inflation of all or part of the lung.

Suspect this on X-ray if:
-Volume loss
-Some opacification
-Displacement of trachea
-Displacement of diaphragm (raised)
-Displacement of lung fissures (superiorly)
-Compensatory over inflation of non collapsed lung (blacker)
-Crowding of vessels & bronchi
Often do not have all abnormalities, but some.

Question 16

Describe the appearance of a LUL atelectasis.

Answer 16

• “veil like” opacification of left lung field
• Elevated hemi-diaphragm (due to loss of volume)
• Loss of cardio mediastinal contour (due to opacification directly adjacent to heart margin)

Question 17

What are the main pathological causes of opacification on a CXR ?

Answer 17

• Consolidation
• Atelectasis
• Pleural effusion

Question 18

Describe the appearance of a pleural effusion on a CXR.

Answer 18

• Mediastinal shift AWAY
• (one side or the other) lower Zone uniformly white
• Concave upper border (meniscus)
• No evidence of air bronchograms

Question 19

What kinds of liquids can be found in pleural effusion ? How may we find out what liquid there is in a pleural effusion ?

Answer 19

Transudate (low protein) - effusion visible on both lung fields (i.e. bilateral blunting of costophrenic recesses), due to increased hydrostatic P pushing fluid out of vessels. Systemic issue, could be Congestive Cardiac Failure.

Exudate (high protein) - large effusion unilaterally (>50% of hemithorax), (malignancy although may not be able to see it due to whiting out, infection, rheumatoid)

Take a history to determine which of these is more likely. To find out definitively what the liquid is, sample the effusion.

Question 20

What are the clinical finds of pleural effusion ?

Answer 20

Inspection: Chest pain, dyspnoea, dry cough
Auscultation: Diminished vocal resonance
Percussion: Stony dullness

Question 21

What are signs of asbestos exposure on a CXR ?

Answer 21

• Calcified plaque (not malignant itself) on pleural cavity

- Mesothelioma (i.e. cancer of pleural lining), present as pleural effusion, but with holly leaf opacification

Question 22

What are possible cardiac abnormalities on a CXR?

Answer 22

HEART FAILURE
5 things to look out for:
A - alveolar (interstitial) oedema (bat wing opacities coming out of hilum)
B - Kerley B lines (“thin linear pulmonary opacities caused by fluid or cellular infiltration into the interstitium of the lungs”)
C - cardiomegaly (i.e. diameter of heart > 50% of thoracic diameter)
D - dilated upper lobe vessels
E - pleural effusion (if pleural effusion present, anticipate it to be small and bilateral, with blunting of costophrenic recesses)

DEVICES IN HEART
Artificial valve
Pacemaker

STERNOTOMY

Question 23

What are possible abnormalities in the diaphragm on a CXR ?

Answer 23

-Air under both hemi-diaphragms (increased translucence under diaphragms). Could be either because of an operation where patient was exposed to air, or laparoscopic operation, or perforated viscus in abdomen (eg perforated peptic ulcer or perforated cancer of bowel)
-A stomach bubble in the left chest (ie above where the diaphragm lies) may indicate diaphragmatic rupture following trauma or
a congenital diaphragmatic hernia in infants.

Question 24

How may we differentiate between free air under the diaphragm, and gastric bubble.

Answer 24

If on the right side at all, free gas (stomach is on the left).
If translucence extends more than half of left hemi-diaphragm, likely to be free gas. If not, may be stomach.
If free gas under both hemi-diaphragms, free gas.
If fairly thin, likely to be free air. If thicker, likely to be stomach.

Question 25

What are possible abnormalities in the external structures on a CXR ?

Answer 25

``` Bone fracture Medical devices (pacemaker, artificial valves, chest drain, tracheostomy tube etc.) ```

Question 26

What are possible abnormalities in the fat and soft tissues, on a CXR ?

Answer 26

- Unilateral breast shadow: may indicate breast cancer (either primary or secondary invasion from primary cancer) - Air in soft tissue: subcutaneous emphysema (trauma, severe asphyxia)

Question 27

Describe some of the features to be looking for when checking the hidden areas on a CXR.

Answer 27

* Neck * Apices (e.g. TB lodges in apex) * Mediastinum: widening, adenopathy, mediastinal emphysema * Retro-cardiac area * Costophrenic angle (Should be nice, sharp, acute. If pleural effusion, the angle will become blunt ) * Behind/below diaphragm (Any free gas, anything in lung tissue behind and below the diaphragm) * Soft tissues * Bones

Question 28

What is a possible abnormality in the hidden areas of a CXR ?

Answer 28

- Atelectasis of the LLL behind the heart - Lingular pneumonia behind the heart - Pleural effusion rendering the costophrenic angle blunt - Mediastinal widening: possibly 1) hilar lymphadenopathy 2) aortic dissection 3) mediastinal emphysema. 1) Bilateral hilar lymphadenopathy (well defined whiteness coming out from hilum) can either be Hodgkin's lymphoma (younger patients) or sarcoidosis (older patients). If unilateral or asymmetrical, could be TB or metastatic spread. 2) Aortic dissection can be due to trauma, atherosclerotic disease/hypertension or be associated with congenital abnormalities such (e.g. Marfans syndrome or Turners syndrome) 3) Mediastinal emphysema: due to asthma, asphyxia, rupture trachea/oesophagus

Question 29

What can cause a person to start having a gravelly voice ?

Answer 29

Recurrent laryngeal nerve invasion

Question 30

Distinguish between a tension pneumothorax and a pneumothorax.

Answer 30

Pneumothorax is the accumulation of air between the rib cage and the lungs i.e. in the pleural space. Tension pneumothorax, is the most severe, life threatening variety of pneumothorax wherein a colossal amount of air is trapped within the chest cavity. In such cases, the wound acts like a one-way valve i.e. air enters the chest cavity during inhalation but has no way to escape. Accumulating air steeply increases the intra-thoracic pressure and, by extension, pressure on important life-sustaining structures in the chest — lungs, heart, major blood vessels, trachea (windpipe). The lung/s on the affected side quickly collapse and mediastinal shift occurs.

Question 31

Distinguish between lobar collapse and atelectasis.

Answer 31

Lobar collapse refers to the collapse of an entire lobe of the lung. As such it is a subtype of atelectasis (although collapse is not entirely synonymous is atelectasis), which is a more generic term for 'incomplete expansion'

Question 32

What are possible causes of under- and over-exansion of the lungs ?

Answer 32

- Under-expansion: Poor compliance | - Over-expansion: Emphysema or bronchiolitis (latter v common in children)

Question 33

What are possible abnormalities in the great vessels on a CXR ?

Answer 33

- Increased size or density of hilar area (lymph node enlargement possibly due to cancer which has spread to the lymph nodes, or due to pulmonary oedema) - Calcium deposits in the elderly (atheroma, atherosclerosis)