Imaging the normal and abnormal lung There is

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Imaging the normal and abnormal lung There is minimal descriptive text in the presenter’s

Imaging the normal and abnormal lung There is minimal descriptive text in the presenter’s notes field Please email me if you have questions Dr I Runcie Consultant Radiologist PRH Ian. [email protected] nhs. uk http: //alberich 4. tripod. com/index. html

Chest X-ray CT scan Ventilation and perfusion imaging

Chest X-ray CT scan Ventilation and perfusion imaging

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This is a radiograph of what appears to be a bunch of grapes. Would

This is a radiograph of what appears to be a bunch of grapes. Would you / could you eat these grapes? 5

Grape in a cup of air 6

Grape in a cup of air 6

Grape in a cup of water 7

Grape in a cup of water 7

What is in this cup of water? 8

What is in this cup of water? 8

The radiologist’s radiographic world view Water - all body fluids and tissues except fat

The radiologist’s radiographic world view Water - all body fluids and tissues except fat and bone Fat Gas High atomic number calcium iodine barium metals 9

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Pulmonary arteries ✓ Pulmonary veins ✓ Bronchi ? 12

Pulmonary arteries ✓ Pulmonary veins ✓ Bronchi ? 12

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CT scan of the lungs Shows greater detail Resolve small structures Resolve small differences

CT scan of the lungs Shows greater detail Resolve small structures Resolve small differences in attenuation

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CT thorax and HRCT lung Slice thickness Resolution Thin section (1 mm) is the

CT thorax and HRCT lung Slice thickness Resolution Thin section (1 mm) is the optimal technique for demonstrating lung CT thorax 5 -8 mm slice thickness 21

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2 1 5 4 4 3

Structure and function The primary pulmonary lobule and acinus 6 -10 mm Secondary pulmonary

Structure and function The primary pulmonary lobule and acinus 6 -10 mm Secondary pulmonary lobule 5 -20 mm diam is the functional unit of the lung. 300 M alveoli per adult – total area 143 m 2

CTS connective tissue septum Secondary Pulmonary Lobule art pulmonary artery v+l vein & lymphatic

CTS connective tissue septum Secondary Pulmonary Lobule art pulmonary artery v+l vein & lymphatic tb terminal bronchus rb respiratory bronchus alveolus venule ac acinus tru terminal respiratory unit or primary bronchiole pok Pore of Khon alv Alveolus 25

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2 1 26

What are lungs for? How could we image function? 28

What are lungs for? How could we image function? 28

Lung function - Gas exchange Ventilation - move air in and out Perfusion -

Lung function - Gas exchange Ventilation - move air in and out Perfusion - move blood in and out Diffusion - moves gases between alveoli and blood 29

How could we obtain a picture of the distribution of ventilation in the lungs?

How could we obtain a picture of the distribution of ventilation in the lungs? 30

Ventilation Radioactive gas - Xenon-133, Krypton-81 m Radioactive aerosol - Tc 99 m-DTPA, Radioactive

Ventilation Radioactive gas - Xenon-133, Krypton-81 m Radioactive aerosol - Tc 99 m-DTPA, Radioactive dry carbon particles 20 nm (0. 02 microns) 50 micrograms Tc 99 m (2 0 rders of magnitude below 24 hour permitted atmospheric pollution) 31

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Normal lung scan 33

Normal lung scan 33

How could we produce a steady state image of lung blood flow? 34

How could we produce a steady state image of lung blood flow? 34

If you inject particles into a peripheral vein where will they stop? Does this

If you inject particles into a peripheral vein where will they stop? Does this carry any risk? 35

Lung perfusion 2 -500, 000 intravenous particles 16 -90 micron diameter Macroaggregated human serum

Lung perfusion 2 -500, 000 intravenous particles 16 -90 micron diameter Macroaggregated human serum albumen Occlude <1% of pulmonary circulation 36

What patient posture would achieve the most uniform distribution of particles throughout the lungs?

What patient posture would achieve the most uniform distribution of particles throughout the lungs? Upright? Lying on the right side? Lying flat on back? 37

Normal lung scan 38

Normal lung scan 38

A few test cases

A few test cases

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R What has happened to the right lung 41

R What has happened to the right lung 41

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What are the round white objects in the lower part of each lung field?

What are the round white objects in the lower part of each lung field? 44

High temperature & cough 45

High temperature & cough 45

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Lung imaging A danger of DIY How is the patient breathing? What might her

Lung imaging A danger of DIY How is the patient breathing? What might her blood gases be like? 49

Air space shadowing = consolidation Fluffy blobs About 1 cm dia Tending to confluence

Air space shadowing = consolidation Fluffy blobs About 1 cm dia Tending to confluence Could be oedema /transudate / exudate / pus / blood +/- air bronchogram

What is missing from much of these lungs? 51

What is missing from much of these lungs? 51

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Is this shadow at the front or the back? 54

Is this shadow at the front or the back? 54

RML consolidation resolved 55

RML consolidation resolved 55

Is this shadow at the front or the back ? 56

Is this shadow at the front or the back ? 56

x 57

x 57

A very thin tramp 58

A very thin tramp 58

What extra shadows can you see in the lungs? 59

What extra shadows can you see in the lungs? 59

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Interstitial shadowing Dots and lines

Interstitial shadowing Dots and lines

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Normal High Resolution CT of lung 64

Normal High Resolution CT of lung 64

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Normal lung scan 69

Normal lung scan 69