4. Computed Tomography
• Numerous
protocols/techniques
depending on clinical
history
• Helical/spiral versus high
resolution
• Contrast
– Renal failure
– Allergy
5. Computed Tomography
• Role of CT
– Main further investigation
for most CXR abnormality
(eg nodule/mass) or to
exclude disease with
normal CXR
– Main investigation for
certain scenarios (PE,
dissection, trauma)
6. MRI
• Multiple planes
• No radiation
• Common Indication
– Pancoast tumour
– Brachial plexus
– Cardiac
– Vascular (aorta)
• Usually targeted
examination (unlike
CT)
Coronal
7. Nuclear Medicine
• Variety of tests: functional rather than
anatomic
• V/Q specific to chest imaging
• Others: bone scan, gallium, WBC etc.
8. Ultrasound
• Limited use in thorax (non cardiac) due to
air in lungs
• Assess pleural effusions
• Mainly used for procedures
9. Chest Radiographs
• PA (posterior to anterior) and Lateral (left)
– Minimizes magnification of heart (heart closest to film)
• Portable (nearly always AP)
– Supine or Erect
• Specialized Views
– Lordotic
– Lateral decubitus (for effusions, pneumothorax)
10. Lordotic View
Better assess apices without bone overlap
11. 1
1: Adequate penetration of
4
a the mediastinum-is the
a thoracic spine seen?
2: Has the patient taken a good
inspiratory effort? About 8-10
7
posterior thoracic ribs should be
seen through the lungs
3: Is there any rotation of the
chest? Assessed by checking
10 the upper thoracic spinous
process (oval) in relation to the
medial ends of the clavicles
(lines ‘a’) - this CXR is rotated to
left
15. Chest Radiograph: Approach and
Normal Anatomy
THERE IS NO ONE APPROACH: BE SYSTEMATIC
• Bone and Soft Tissue including abdomen
• Heart
• Mediastinum-aorta, trachea
• Hila
• Pulmonary Vasculature
• Lungs
• Pleura
16. Sequence For X Ray Reading
5 Ds
• Detect
• Describe
• Differential Diagnosis
• Discuss
• Diagnosis
24. Pulmonary Artery
Left Lung
Coronal Image
PA
Lung “markings”
are
pulmonary arteries
and veins
25. • Spine Sign: Lungs
posteriorly should get
Scapula
darker as you go down
inspexp more inferiorly
Retrosternal
Airspace
Hilum
IVC
Pulmonary
Vessels
26. Case: (Look at the trachea)
Trachea is
Deviated by
large mass
(goiter)
27. Abnormal Cases
• Bone
• Cardiovascular
• Airspace Disease including Silhouette Sign
• Interstitial Disease and Pulmonary Edema
• Atelectasis
• Pulmonary Nodule
• Pleura and Diaphragm
• Mediastinal Mass
28.
29. ACINAR PATTERN (CXR)
Radiology: Round or elliptical ill-defined 4-8mm opacities in lung
Microscopic: Portion of lung distal to terminal bronchial (respiratory bronchial,
alveolar duct, alveolar sac and alveoli) is the acinus
CXR close up of acinar pattern
30. ACINAR PATTERN (CT SCAN)
Round or elliptical ill-defined 4-8mm opacities in
lung
CT scan of right upper lobe
showing typical acinar pattern
(arrow)
32. NODULAR PATTERN
Collection of innumerable small, linear and nodular opacities
together producing a net with small superimposed nodules.
CT
CXR
Close up of nodular pattern
33. EMPHYSEMA:
Abnormally expanded air spaces distal to terminal
bronchiole with destruction of walls of involved air
spaces..
BULLA: Gas containing avascularity of lung measuring 1cm or more in
diameter, 1mm thickness
Bulla CT of bulla
34. Pneumonia (consolidation)
• Air bronchograms would confirm an alveolar process.
• The lung volume should not be lost (may even be
increased).
• Usually all radiographic abnormalities should disappear
after 6 weeks of appropriate antibiotic therapy.
40. Consolidation and follow-up X-rays
• Recommendations are, repeat film at 1, 3 and 7 days to check for
the development of complications.
• Resolution of the X-ray signs always lags behind the clinical
findings
• The X-ray should therefore be repeated 4 weeks later to check for
resolution.
• If there is persistent consolidation at this stage, further investigation
is necessary to exclude an obstructive lesion.
41. SIGNS OF COLLAPSE
DIRECT SIGNS:
• Displacement of fissures
• Loss of aeration
• Vascular & bronchial signs
INDIRECT SIGNS:
• Mediastinal & Hilar displacement
• Elevation of Hemidiphragm
• Compensatory hyperinflation
72. Severe heart failure
• Severe pulmonary edema gives confluent
alveolar shadowing which spreads out from the
hilum giving a 'bat's wing' appearance.
• If this is the cause of generalized shadowing
then upper lobe blood diversion and Kerley B
lines should be present.
• In pulmonary edema hilum may appear
distended and the vessels close to the hilum
may be blurred.
73. Severe heart failure vs. non-
carcinogenic pulmonary edema
• In non-cardiogenic pulmonary edema the heart
size is likely to be normal and there will not
necessarily be sparing of the peripheries.
