radiology: chest imaging

38
Chest Imaging

Upload: scgh-ed-cme

Post on 07-May-2015

1.706 views

Category:

Health & Medicine


0 download

DESCRIPTION

chest radiology

TRANSCRIPT

Page 1: Radiology: Chest Imaging

Chest Imaging

Page 2: Radiology: Chest Imaging

Densities

• Four densities on XR• Black – air/gas• Dark grey – fat• Light grey – fluid/solid organ• White – bone/calcium

Increasing opacification

Page 3: Radiology: Chest Imaging

CXR

• Rule No 1! – always check name of patient and date

• Check orientation (L & R labeled correctly)• Projection (PA or AP, lateral, decubitus,

supine)• Accurate assessment of heart size and

mediastinum on PA views• All supine/portable - AP

Page 4: Radiology: Chest Imaging

CXR - systematic• ABCDE for both frontal & lateral projection• A – airways

– Trachea/central bronchi midline or just to right, no narrowing, carinal angle <90°

• B – breathing/lungs– Parenchyma – too white or too black?

• Look at the fissures

– Bones – ribs, vertebrae, humeri clavicles, scapulae – for fractures, lytic(black), sclerotic (white) lesions, vertebral body heights

• C – cardiac/vessels– Cardiac silhouette & Mediastinum contours & width– Hilum – normal hilar shadow made up of vessels, Lt is higher than right by 0-2.5

cm. Must have concave shape– Pulmonary vessels – upper zone vessels vessels smaller than lower

Page 5: Radiology: Chest Imaging

CXR - systematic

• D – look under the diaphragm– free gas – perforated viscus– Costophrenic angle for pleural effusion

• E – extremities– The corners of the film

• Line position• Hidden areas: lung apices, behind the heart,

breast shadows, paravertebral, thyroid

Page 6: Radiology: Chest Imaging

Normal CXRTrachea

Rt Mainstem bronchus

Aortic Arch

Pulm artery

Pulm artery

LV

Diaphragm

stomach

RA

Atrial appendage

Page 7: Radiology: Chest Imaging

Normal CXR

Trachea

Pulmonary artery

RVLV

Aortic arch

Costophrenic angle

LA

Page 8: Radiology: Chest Imaging

Anatomy

RUL

ML

RLL

LUL

LLL

Page 9: Radiology: Chest Imaging

Heart

• Cardiothoracic ratio (CTR)– <50% adults– PA film – AP magnifies heart– Causes of increased CTR

• Obesity, pectus, portable film, cardiomegaly, pericardial effusion

• Shape• Valve calcification

Page 10: Radiology: Chest Imaging

Lungs• Too black• Too white

– Opacity, density, infiltrate, mass/nodule• Alveolar air cells

– Normally contain air (black)– Cells eg infection/inflam pus, tumour, eosinophils– Fluid eg aspiration, drowning, oedema, haemorrhage

• Interstitial• Collapse V consolidation

– Volume loss: mediastinal shift, fissures, diaphragm, hilum, rib crowding

– Air bronchograms

Page 11: Radiology: Chest Imaging

Silhouette sign

• When air in alveoli replaced with fluid/cells contrast between the lung and the neighbouring structure (heart, diaphragm) is lost and borders become indistinct.

• Use the silhouette sign to determine which lobe of the lung consolidation is in.

Page 12: Radiology: Chest Imaging

14 y M

Page 13: Radiology: Chest Imaging

Hx: 61 y M SOB

Page 14: Radiology: Chest Imaging

10 y F bilateral crackles. No response to ventolin

Page 15: Radiology: Chest Imaging

Hx 60 y M, chronic cough, haemoptysis

Page 16: Radiology: Chest Imaging

Hx 12 Y F fever & cough

Page 17: Radiology: Chest Imaging

Hx: 5Y M reduced air sounds left chest, decrease O2 sat

Page 18: Radiology: Chest Imaging

Hx 23 F confusion

Page 19: Radiology: Chest Imaging

66 Y F SOB

Page 20: Radiology: Chest Imaging

FHx: 54 y M SOB

Page 21: Radiology: Chest Imaging

Hx 41 Y F

Page 22: Radiology: Chest Imaging

Hx 16 Y M known malignancy

Page 23: Radiology: Chest Imaging

Hx: 88 Y M fever weight loss

Page 24: Radiology: Chest Imaging

Hx 78 Y F previous rectal cancer

Page 25: Radiology: Chest Imaging

The Black Lung

• First consider Rotation: – (look at the clavicles)– The lung closer to the film plate will absorb

more of the x-rays and so be whiter, whilst the lung further away allows distance for scattered rays to get through, and so will be blacker

Page 26: Radiology: Chest Imaging

9 y M Wheeze

Page 27: Radiology: Chest Imaging

23 y M

Page 28: Radiology: Chest Imaging

21 y M chest pain

Page 29: Radiology: Chest Imaging

20 Y M

Page 30: Radiology: Chest Imaging

87 y M SOB

pseudopneumothorax

Page 31: Radiology: Chest Imaging

Pulmonary embolism

• Abnormalities seen on CXR in PE– MORE OFTEN NORMAL – never forget this!!– Segments/subsegments of linear atelectasis– Raised hemidiaphragm– Focal region of hyperlucency (oligaemia) “Westermark’s sign” – black area of lung seen in only 2%

– Peripheral foci of consolidation (infarction) e.g. Hampton’s Hump. <10% show infarction.

– Dilated central arteries due to arterial hypertension.– Abrupt cut-off of a vessel – only if in the central

arteries– Pleural effusion

Page 32: Radiology: Chest Imaging

38 y M

Page 33: Radiology: Chest Imaging
Page 34: Radiology: Chest Imaging

Pleural Plaques

• Associated with asbestos exposure• Thickening of the parietal pleura which

calcifies, especially seen over the diaphragmatic surface as dense linear bands.

• Does NOT equal asbestosis, which is pulmonary parenchymal disease related to asbestos exposure – can occur together.

Page 35: Radiology: Chest Imaging

77 y M

Page 36: Radiology: Chest Imaging

• Hilar Enlargement – unilateral or bilateral – Look for the convex contour

• Neoplasm: – central bronchogenic tumour itself, or lymphadenopathy. e.g. Ca

Bronchus, lymphoma, Lymphangitis carcinomatosis• Infective e.g. TB (usually unilateral), Mycoplasma, Viral in children• Sarcoidosis rarely unilateral, very symmetrical• Post-stenotic dilatation of pulmonary artery• Pulmonary artery aneurysm (very rare)• All causes of pulmonary arterial hypertension: primary (idiopathic) or

secondary e.g. COAD, long- term PE, chronic left to right cardiac shunt.

Page 37: Radiology: Chest Imaging

Mediastinum• When reviewing CXR, don’t forget this

region, which contains the oesophagus, the trachea, the aorta, the thymus

• Differential Diagnosis of an anterior Mediastinal mass: “The 4 Ts”

• Thymoma• Thyroid goitre• Teratoma• Terrible Lymphoma• Assessing the mediastinal width after

severe road trauma is important to assess for

– aortic rupture. However, these films are always supine (so AP) so very variable!!

• In practice, if the widest part of the upper mediastinum is >30% of the total thorax diameter at that level, suspect aortic injury if clinically possible. However, NEVER ignore high clinical suspicion even if the xray seems normal.

Page 38: Radiology: Chest Imaging

14 y M