Chest Masterclass

Question 1

how does X ray make an image?

Answer 1

compares densities
- more dense = whiter
less dense = darker

Question 2

process of interpreting an X ray?

Answer 2

check name and CHI
is there a side marker?
is it technically accurate
- projection
- inspiration
- rotation
- penetration

Question 3

PA radiograph?

Answer 3

…

Question 4

normal cardiothoracic ratio?

Answer 4

<0.5

Question 5

how is cardiothoraciC ratio (CTR) measured?

Answer 5

PA x-ray

not AP as objects close to the x ray tube are enlarged so the heart would look bigger on AP

Question 6

why is a large inspiration in CXR important?

Answer 6

to see at least 6 ribs

can look like pathology of not fully inspired

Question 7

how can you tell if CXR is centred?

Answer 7

medial ends of clavicles are equal distance from spinous processes

Question 8

mediastinal borders on CXR?

Answer 8

aorta
pulmonary artery
left auricle
left ventricle
right atrium
trachea
hemidiaphragm
stomach bubble
horizontal fissure
- should all be seen on CXR

Question 9

what are pulmonary hila?

Answer 9

junctions between the heart and lungs
where the pulmonary arteries and bronchi enter and the pulmonary veins exit the lungs
mainly arteries (veins small)

Question 10

which hilum generally sits higher?

Answer 10

left

- come out above the bronchus which the right comes out below

Question 11

normal difference in diaphragm height?

Answer 11

right side 1.5cm higher

Question 12

zones of lungs?

Answer 12

not same as lobes
lungs divided into
 - upper (to 2nd rib)
- middle (2-5)
- lower (below 5)
should be roughly same size

Question 13

review areas/

Answer 13

ares where things are missed

• lung apices (masses etc)
• behind heart (consolidation etc)
• below diaphragm (gas bubbles, gastic things etc)
• bones and soft tissue

Question 14

lingula is found in which lung?

Answer 14

left lower lobe

Question 15

what causes lobar collapse?

Answer 15

blockage in bronchus (lobe supplied by obstructed bronchus isnt ventilated and its air gets reabsorbed so lobe looses volume and collapses)

Question 16

signs of lobe collapse?

Answer 16

reduced volume in lung

• sail sign
• higher diaphragm

Question 17

how does upper lobe collapse present?

Answer 17

collapses forward against anterior chest wall
heart becomes less visible
volume loss causing higher diaphragm etc
“veil like opacity” in upper lobe

Question 18

how does middle lobe collapse present?

Answer 18

smallest lobe so not much volume loss seen
obscuration of righ atrium loss of clarity of right heart border
preservation of the diaphragm on that side

Question 19

what can cause collapse of middle and lower right lobes?

Answer 19

blockage in bronchus intermedius (common bronchus which splits to supply air to middle and lower lobes)

Question 20

how does consolidation present?

Answer 20

diaphragm preserved

may have clouding of other mediastinal features but no volume loss?

Question 21

air bronchograms?

Answer 21

tubular outline of an airway made visible by filling of the surrounding alveoli with fluid/exudate etc (e.g from infection)
specific for consolidation?

Question 22

should pleural cavity be visible if normal?

Answer 22

no

Question 23

when is pleural cavity seen?

Answer 23

pleural effusion
- fluid gathers at lung bases if upright and often forms curved meniscus sign (blunt costophrenic recess)
pneumothorax

Question 24

larger pleural effusion?

Answer 24

more homogenous

meniscus sign tracks against the lobes

Question 25

what is seen in pneumothorax?

Answer 25

clear black crescent overlying edge of lung markings clear black area surrounding lung if larger (lung edge should not be visible in normal lungs as stuck to pleura)

Question 26

how does large tension pneumothorax present?

Answer 26

large air filled space displaces mediastinum and trachea | heart can be pushed over to other side

Question 27

signs of pulmonary oedema (heart failure) in order?

Answer 27

1. dilation of upper lobe vessels and right side of heart (then left side) - upper lobe veins should be pencil thin and hard to see) 2. interstitial opacities (fluid overspills into interstitium which supports the lungs) 3. airspace opacification (alveoli causing cotton wool appearence, perihilar/batwing effusion) 4. pleural effusion

Question 28

ABCDE of heart failure signs?

Answer 28

``` alveolar bat wings kerly B lines cardiomegaly dilated upper lobe vessels edema ```

Question 29

tubes which may be seen on CXR?

Answer 29

endotracheal tubes -normal = 5cm abover carina, 2/3 width of trachea, balloon cuff should not expand trache - abnormal = tip extends past carina inot right main bronchus, may enter oesophagus) nasogastric tube - normal = in subdiaphragmatic position in stomach (overlying gastric bubble on CXR), 10cm beyond gastro-oesophageal junction - abnormal = tip in oesophagus, bronchus/lung, coiled un upper airway, intracranial in case of skull fracture Central venous catheters - inserted via right or left internal jugular or subclavian veins but has to enter right side SVC - 2nd intercostal space is normal place of tip - abnormal = too high in proximal SVC - ........

Question 30

what might malpositioned endotracheal tube cause?

Answer 30

lung collapse | if too far into right bronchus, only right lung will be inflated

Question 31

nodule classification based on size?

Answer 31

miliary nodule = <2mm pulmonary micronodule = 2-7mm pulmonary nodule = 7-30mm pulmonary mass = >30mm

Question 32

distribution of pulmonary nodules?

Answer 32

perilymphatic centrilobular random

Question 33

morphology of pulmonary nodules?

Answer 33

solid partly solid ground glass

Question 34

primary lung cancer tend to be where?

Answer 34

apical (where the smoke does) | metastases = lower (where most blood vessels are)

Question 35

cancer staging?

Answer 35

TNM - tumour size - nodes - metastases

Question 36

investigations in suspected lung cancer?

Answer 36

``` contract enhanced CT - asses size, mets and biopsy guidacne FDG-PET CT - nodal metastases - distant mets - delineating tumour ```

Question 37

what is pneumoperitoneum?

Answer 37

perforation of hollow organ results in gas in peritoneal cavity gas rises up above the diaphragm seen as a thin black line between diaphragma nd sub-diaphragmatic structures

Question 38

PE presentation?

Answer 38

``` dyspnoea pleuritic chest pain cough orthopnoea haemoptysis signs of DVT in leg ```

Question 39

PE investigation?

Answer 39

``` D dimers (can rule out but not confirm) CTPA = gold standard as visualises the clot ```

Question 40

PE x ray features?

Answer 40

usually normal or show non-specific findings | only really used to look for alternative causes of symptoms

Question 41

CTPA features of PE?

Answer 41

clot can be visualised

Question 42

V/Q scan features of PE?

Answer 42

looks for defects caused by the clot | mis-matched perfusion defect

Question 43

how might the heart be affected by PE?

Answer 43

enlarged right side as it cant pump blood out against blockage in pulmonary artery contrast/blood can back up into IVC etc