Dr. Emad Efat provides a tutorial on chest x-ray fundamentals that includes:
1. A systematic approach for analyzing chest x-rays that involves checking anatomical structures, patient and image data, describing abnormalities, and interpreting findings based on clinical context.
2. Guidelines for assessing chest x-ray quality including factors like inclusion, projection, rotation, inspiration, penetration, and artifacts that can impact the ability to identify abnormalities.
3. An overview of chest x-ray anatomy covering structures like the airways, hilar regions, lung zones, pleura, lung lobes/fissures, diaphragm, heart contours and size, and mediastinum.
5. Systematic approach - Patient and image data
Check the patient's identity
Note the image date and time
Note the image projection: Check if a posterior anterior
(PA) or anterior posterior (AP) projection was used, and
note if the patient was standing, sitting or supine? Was
the mobile X-ray machine used?
The image annotations are often useful:
This is a mobile chest X-ray
taken with the patient supine,
at 11.25 am in the resuscitation
room. The patient's name, ID
number and date of birth are
annotated. Note the side
marker is correct.
7. Systematic approach - Image quality
Assess the image quality: The chest X-ray should be
checked for rotation, inspiration and penetration
(Mnemonic-RIP-Rest In Peace ).
Comment on the presence of medical artifacts
Can the clinical question still be answered?
8. Systematic approach - The obvious abnormality
It is often appropriate to start by describing the most
striking abnormality. However, once you have done this,
it is vital to continue checking the rest of the image.
Remember that the most obvious abnormality may not
be the most clinically important.
The elephant in the
image!
If there is an elephant
in the image, don't
ignore it! Describe it
in detail and then use
your system to
continue examining the
image.
9. Systematic approach - Describing abnormalities
'Shadowing', 'Opacification', 'increased density',
'increased whiteness' are all acceptable terms
'Lesion descriptors' may lead you towards a diagnosis
Be descriptive rather than jumping to a diagnosis
'Lesion descriptors'
6. Position Anterior/
Posterior/Lung zone etc.
7. Shape Round/ Crescentic/etc.
8. Edge Smooth/
Irregular/Spiculated
9. Pattern Nodular/
Reticular(netlike)
10.Density Air/ Fat/Soft tissue/
Calcium/Metal
1. Tissue involved Lung,
heart, aorta, bone etc.
2. Size Large/ Small/Varied
3. Side Right/ Left
Unilateral/ Bilateral
4. Number Single/ Multiple
5. Distribution Focal/
Widespread
10. Systematic approach - Describing abnormalities
'Shadows, opacities, densities'
Tissue involved: Lung
Size: Small (>2 cm)
Side: Bilateral
Number: Multiple
Distribution: Widespread
Position: Mainly middle
to lower zones
Shape: Round
Edge: Irregular
Pattern: Nodular
Density: Soft tissue
Diagnosis:
Description helps with diagnosis. Once you have put all the above terms
together, there can only be one diagnosis.
Metastatic disease
11. Systematic approach - Locating abnormalities
Consider its anterior-posterior position.
A lateral view may help, but 3D location may also be
possible on a posterior-anterior (PA) view if you have a
knowledge of chest X-ray anatomy and an understanding
of the 'silhouette' sign.
The 'silhouette' sign:
The silhouette sign is a misnomer !
It should be called the 'loss of silhouette' sign.
Normal adjacent anatomical structures of differing
densities form a crisp 'silhouette,' or contour.
Loss of a specific contour can help determine
the position of a disease process.
12. Systematic approach - Locating abnormalities
The 'silhouette' sign: Loss of contour of :
1 - Left heart border Lingula disease
2 - Hemidiaphragm Lower lobe lung disease
3 - Paratracheal stripe Paratracheal disease
4 - Chest wall Lung, pleural or rib disease
13. Systematic approach - Locating abnormalities
The 'silhouette' sign: Loss of contour of :
5 - Aortic knuckle Anterior mediastinal or left upper lobe disease
6 - Paraspinal line Posterior thorax disease
7 - Right heart border Middle lobe disease
14. Systematic approach - Review areas
After a systematic look at the whole chest X-ray, it is worth
re-checking hidden areas that may conceal important
pathology.
Hidden areas:
• Apical zones
• Hilar zones
• Retrocardial zone
• Zone below the
dome of diaphragm
15. Systematic approach - Interpretation
Whatever the findings are,
they should only be
interpreted in view of the
clinical setting.
Remember to treat the
patient - not the X-ray!
Occasionally there will be
an unexpected finding
(Incidental Finding), which
may need to be considered
with caution, especially if
equivocal or if it does not
fit the clinical scenario.
Posteroanterior (PA) chest
radiograph shows an incidental
finding of a solitary pulmonary
nodule adjacent to the left hilum.
16. Chest X-ray quality - Inclusion
Check the image for: Inclusion, Projection, Rotation,
Inspiration, Penetration and Artifact.
Check to see if a poor quality X-ray demonstrates a life
threatening abnormality before dismissing it.
Check to see if the clinical question still be answered?
Inclusion:
A chest X-ray
should include
the entire thoracic
cage ( first ribs,
Costophrenic
angles, Lateral
edges of ribs ).
17. Chest X-ray quality - Projection
AP projection :
AP projection image is of
lower quality than PA image.
The scapulae are not retracted
laterally and they remain
projected over each lung.
Heart size is exaggerated
18. Chest X-ray quality - Rotation
Rotation:
The spinous processes should lie
half way between the medial
ends of the clavicles
Rotation affects heart size &
shape, aortic tortuosity, tracheal
position and density of lung fields
Rotation can obscure a
pneumothorax . Can also mimic a
mediastinal shift.
Rotation may cause an increase in the transradiancy (blackness)
of the lung on the side to which the patient is rotated.
Rotation will also alter the relative appearance on the hila and
can mimic hilar asymmetry.
20. Chest X-ray quality - Rotation
Frontal chest x-Ray (CXR) with subject rotated to
the left. Note an enlarged heart and small left
pleural effusion. The left hemithorax is darker
than the right due to the rotation.
21. Chest X-ray quality - Inspiration & lung volume
Assessing inspiration:
Count ribs down to
the diaphragm.
The diaphragm
should be
intersected by:
the 5th to 7th (right
6th anterior rib )
anterior ribs in the
mid-clavicular line or
The 8th–10th (9th)
posterior ribs . CXR in full inspiration
22. If the image is acquired in the
expiratory phase or with a
poor inspiratory effort:
1. The lungs are relatively airless
and their density is increased.
2. Increase in lower zone
opacity
3. The hila are compressed and
appear more bulky
4. Exaggeration of heart size
5. Obscuration of the lung
bases.
Chest X-ray quality - Inspiration & lung volume
poor inspiratory effort
full inspiration the same patient
23. Chest X-ray quality - Penetration
Differential Absorption:
Penetration of the x-ray
beam is dependent on
tissue density
Denser object = Less
beam striking the
film (more
absorption) = whiter
Less dense = More
beam striking the
film = blacker
24. Chest X-ray quality - Penetration
A well penetrated (exposed) chest X-ray :
The end plates of the lower thoracic vertebral bodies
should be just visible through the cardiac shadow.
The left hemidiaphragm should be visible to the edge
of the spine.
25. Chest X-ray quality - Penetration
Good penetration
You should be able
to just see the
thoracic spine
through the heart
26. Chest X-ray quality - Penetration
An under-penetrated film looks diffusely opaque (too
white), structures behind the heart are obscured, and
left lower lobe pathology may be easily missed.
An over-penetrated film looks diffusely lucent, the lungs
appear blacker than usual and the vascular markings and
lung detail are poorly seen.
27. Chest X-ray quality - Artifact
Radiographic artifact
Rotation, incomplete inspiration
and incorrect penetration. Other
radiographic artifact includes
clothing or jewellery not
removed.
Patient artifact
Poor co-operation with
positioning or movement. Very
often obesity exaggerates lung
density. Occasionally normal
anatomical structures such as hair
or skin folds can cause confusion. Hair artifact
28. Chest X-ray anatomy - Airways
Assessing the airways
Start your assessment of
every X-ray by looking at the
airways.
The trachea should be central
or slightly to the right.
If the trachea is deviated:
If the patient is rotated, or if
there is pathology.
If the trachea is deviated:
If it has been pushed or
pulled by a disease process.
The trachea branches at the
carina, into the left and right
main bronchi, and these can
often be followed as they
branch beyond the hila and
into the lungs.
29. Chest X-ray anatomy - Airways
large left pleural
effusion, and
tracheal shift away
from the effusion
Tension pneumothorax
with tracheal deviation
to right
Tracheal shift to the
right due to thyroid
enlargement
Causes of tracheal deviation:
Ipsilateral (To pull): Collapse and Fibrosis
Contralateral ( To push): Apical mass , Pleural effusion
and Pneumothorax
30. Chest X-ray anatomy - Hilar structures
The structures contributing to
hilar shadows are:
Major: Pulmonary artery and veins
Minor: Fat, Lymph nodes and
Bronchial walls (not visible unless
abnormal)
Normal Hilum:
Position: Left hilum is slightly
higher than the right hilum, Only in
a minority of cases the right hilus is
at the same level as the left, but
never higher.
Shape: Concave
Size: Similar on both sides
Density: Almost same on both sides
Deoxygenated blood (blue
arrow) is pumped upwards out
of the right ventricle (RV) via
the main pulmonary artery
(MPA). This divides into left
(LPA) and right (RPA) which
each pass via the lung hila into
the lung tissue
31. Chest X-ray anatomy - Hilar structures
The hilar points: the angle formed
by the descending upper lobe
veins, as they cross behind the
lower lobe arteries
Not every normal patient has a
very clear hilar point on both
sides, but if they are present then
they can be useful in determining
the position of the hila.
Identify main lower lobe
pulmonary arteries: They
can be compared to a
little finger pointing
downwards and medially.
32. Chest X-ray anatomy - Lung zones
The chest radiograph zones:
1. Apical zone: above the
clavicles
2. Upper zone: below the
clavicles and above the
cardiac silhouette (i.e. up to
lower margin of 2nd rib )
3. Mid zone: the level of the
hilar structures (i.e. from
lower margin of 2nd rib to
lower margin of 4th rib )
4. Lower zone: the bases ( i.e. from 4th rib to diaphragm )
33. Chest X-ray anatomy - Pleura and pleural spaces
Trace round the entire edge
of the lung where pleural
abnormalities are seen.
Start and end at the hila
Is there pleural thickening?
Is there a pneumothorax?
The lung markings should
be visible to the chest wall
Is there an effusion? The
costophrenic angles and
hemidiaphragms should be
well defined
34. Chest X-ray anatomy - Pleura and pleural spaces
Costophrenic recesses and
angles:
The costophrenic angles
are limited views of the
costophrenic recess
On a frontal view the
costophrenic angles
should be sharp.
The costophrenic angles
consist of the lateral
chest wall and the dome
of each hemidiaphragm.
35. Chest X-ray anatomy - Lung lobes and fissures
In the right lung there
is an oblique fissure
( of ) and a horizontal
fissure ( hf ) ,
separating the lung into
three lobes - upper,
middle, and lower.
Each lobe has its own
visceral pleural
covering.
36. Chest X-ray anatomy - Lung lobes and fissures
The left lung is
divided into two
lobes, upper and
lower.
These lobes have
their own pleural
covering and these
lie together to form
the oblique (major)
fissure ( of ).
37. Chest X-ray anatomy - Diaphragm
The hemidiaphragms are not
at the same level on frontal
erect inspiratory chest
radiographs, but are usually
within one rib intercostal space
height (2 cm) of each other.
The left hemidiaphragm is
usually lower than the right.
If the left hemidiaphragm is
higher than the right or the
right is higher than the left by
more than 3 cm, one of the
many causes of diaphragmatic
elevation should be considered.
38. Chest X-ray anatomy - Diaphragm
Hemidiaphragms - lateral
view:
The left and right
hemidiaphragms are
almost superimposed on
a lateral view.
Anteriorly the left
hemidiaphragm blends
with the heart and
becomes indistinct.
39. Chest X-ray anatomy - Heart size and contours
From superior to inferior:
1. Right paratracheal stripe:
made up of right
brachiocephalic vein and SVC
2. Arch of the azygous vein
3. Ascending aorta in older
individuals projects to the
right of the SVC
4. Superior vena cava (SVC)
5. Right atrium
6. Inferior vena cava (IVC)
The normal contours of the heart and mediastinum
(cardiomediastinal contour):
Right cardiomediastinal contour
40. Chest X-ray anatomy - Heart size and contours
From superior to inferior:
Left paratracheal stripe
Made up of left common
carotid artery, left subclavian
artery and the left jugular vein
Aortic arch +/- aortic nipple
(left superior intercostal vein)
Pulmonary artery
Auricle of left atrium
Left ventricle
The normal contours of the heart and mediastinum
(cardiomediastinal contour):
Left cardiomediastinal contour
42. Chest X-ray anatomy - Heart size and contours
Lateral view:
Anterior cardiomediastinal contour
From superior to inferior:
1. Superior mediastinum
1. great vessels
2. thymus
2. Ascending aorta
3. Right ventricular outflow track
4. Right ventricle
Posterior cardiomediastinal contour
From superior to inferior:
1. Left atrium and pulmonary veins
2. Right atrium
3. Inferior vena cava
43. Chest X-ray anatomy - Heart size and contours
Cardiothoracic ratio:
The cardiothoracic ratio
should be less than 0.5. i.e.
A+B/C<0.5
A cardiothoracic ratio > 0.5
suggests cardiomegaly in
adults
A cardiothoracic ratio > 0.6
suggests cardiomegaly in
newborn.
44. Chest X-ray anatomy - Heart size and contours
There are several structures in the superior mediastinum
that should always be checked. These include the aortic
knuckle, the aorto-pulmonary window, and the right
para-tracheal stripe.
45. Chest X-ray anatomy - Heart size and contours
It is a space
located between
the arch of the
aorta and the
pulmonary
arteries.
This space can be
lost as a result of
mediastinal
lymphadenopathy
(e.g. malignancy).
The aorto-pulmonary window:
Aortic knuckle (red arrow) &
Aortopulmonary window (green arrow)
46. Chest X-ray anatomy - Mediastinum
In lateral CXR, mediastinum divided into :
Superior mediastinum (S): above the
thoracic plane or the plane of Ludwig
(a horizontal line that runs from sternal
angle or angle of Louis) to the inferior
endplate of T4)
Inferior mediastinum: below the plane of
Ludwig
Anterior mediastinum (A): anterior to
the pericardium
Middle mediastinum (M): within the
pericardium
Posterior mediastinum (P): posterior to
the pericardium
In PA view, the mediastinum is that space
between the lungs and pleural surfaces
(yellow lines).
47. Chest X-ray anatomy - Bones and Soft tissues
Bones:
Ribs (anterior
and posterior)
Clavicles and
shoulders
Sternum
Vertebrae
Shoulder joints
Soft tissues :
Breast shadows
Skin folds
Muscles
Check for: Symmetry, Deformities, Fractures, Masses, Calcifications
and Lytic lesions .
49. Chest X-ray anatomy - Lateral view
Interpretation of lateral film
The clear spaces
Retrosternal space
Retrotracheal
space
Retro cardiac
Vertebral
translucency
Diaphragm outline
The fissures
The trachea
The sternum
50. Chest X-ray anatomy - Lateral view
Retrosternal space
Seen as a normal lucency
between the posterior aspect
of the sternum and anterior
aspect of the ascending aorta
This space should be visible
and less than 2.5cm in width.
Can be demonstrated at point
3cm below manibrium sterni
An increased retrosternal
airspace is a reliable sign of
pulmonary emphysema, while
obliteration indicates anterior
mediastinal mass e.g.
lymphoma.
51. Chest X-ray anatomy: Lateral view
Vertebral translucency
The ‘‘spine sign,’’ which
states that the normal
lateral chest film shows
increasing overall lucency
as one looks down the
thoracic vertebral bodies
from the neck to the
diaphragms.
Causes of failure to darken
gradually above the
diaphragms:
Pleural thickening
Lower lobe collapse
Mediastinal mass
52. Chest X-ray anatomy - Lateral view
Diaphragm outline
Right
hemidiaphragm
continues
anteriorly
left
hemidiaphragm
blends with the
heart and
becomes
indistinct
Anteriorly.
53. Chest X-ray anatomy - The fissures
The oblique fissures
(the major fissures or
greater fissures):
begins roughly at the
spinous process of the
T4 level of the thoracic
spine and ends at the
anterior costophrenic
angle
The right lung
54. Chest X-ray anatomy - The fissures
The horizontal fissure
(the minor fissure):
running horizontally
from the edge of right
lung towards the right
hilum, at approximately
the level of the anterior
4th rib
The right lung
Consolidation abutting the horizontal
fissure allows it to be localized to the
right upper lobe (arrow)
55. Chest X-ray anatomy - The fissures
The oblique fissures
(the major fissures
or greater fissures):
begins between the
spinous processes of
vertebrae T3 and T4
and ends about 5 cm
posterior to the
anterior costophrenic
angle
The left lung
56. How to speak - Normal CXR
This is chest radiograph, PA view with
normal exposure, no rotation and without
any apparent bony abnormality. Trachea is
placed centrally & lung fields are clear with
normal broncho-vescicular markings.
Cardiovascular silhouette is within normal
limits with normal cardiothoracic ratio.
Mediastinum, costo-phrenic, cardio-phrenic
angles, dome of diaphragm & soft tissue
shadow within normal limits.
57. Chest X-ray Abnormalities - Trachea
Ensure trachea is visible and in midline
1. Tracheal displacement (discussed previously)
2. Trachea normally narrows at the vocal cords
3. View the carina, angle should be between 60 –100
degrees. Beware of things that may increase this angle,
e.g. left atrial enlargement, lymph node enlargement and
left upper lobe atelectasis
4. Follow out both main stem bronchi
5. Check for tubes, foreign bodies etc.
6. If an endotracheal tube is in place, check the positioning,
the distal tip of the tube should be 5-7cm above the
carina
59. Chest X-ray Abnormalities - Trachea
In this patient, the endotracheal tube is in the right
mainstem bronchus, and the left sided is not being
ventilated. That is why the left side is collapsed
60. Chest X-ray Abnormalities - The lung hilum
A. Hilar position:
If a hilum has moved, you should try to determine if it has
been pushed or pulled, just like you would for the
trachea.
The left hilum must never be lower than the right hilum.
Whenever a left hilum appears lower than the right hilum
– look for other evidence suggestive of:
Collapse of either the left lower lobe or of the right
upper lobe
Enlargement of the right hilum
61. Chest X-ray Abnormalities - The lung hilum
A. Hilar position:
Superior displacement and
horizontalization of the right hilum
(white curved arrow) due to
atelectasis of the right upper lobe
(black arrows). the hilum (red arrow)
Left lower lobe atelectasis. The blue
arrows point to the edge of a
triangular region of atelectatic left
lower lobe. Left Hilum displaced
inferiorly. the hilum (red arrow)
62. Chest X-ray Abnormalities - The lung hilum
B. Hilar enlargement:
May be unilateral or bilateral, symmetrical or asymmetrical
63. Chest X-ray Abnormalities - The lung hilum
Analyze the enlargement of
hilum (if present):
1. Lymph Node enlargement:
Lobulated appearance
(lumpy-bumpy opacity )
Presence of calcification
within the mass
indicates usually
tuberculosis.
Egg-shell calcification
indicates silicosis or
sarcoidosis. Calcified bilateral hilar
lymphadenopathy in
sarcoidosis
64. Chest X-ray Abnormalities - The lung hilum
2. Arterial enlargement:
Smooth margins
In pulmonary arterial
hypertension the
arteries in the outer
two-thirds of each
lung are smaller than
those at the hila
(peripheral pruning)
Primary pulmonary hypertension showing
right heart enlargement and enlargement
of the main pulmonary artery and its right
and left branches.
65. Chest X-ray Abnormalities - The lung hilum
3. Malignancy:
Spiculated irregular or
indistinct margins
Hilar enlargement due
to malignant lung lesion
is also associated with
superior mediastinal
lymphadenopathy. Look
at the lung fields (for
presence of tumor) and
bone/ribs for
metastasis.
This patient has a bulky right
hilum. This was shown to be due
to a bronchogenic tumour.
66. Chest X-ray Abnormalities - The lung hilum
C. Hilar density:
May be due to :
A mass or calcification in
the hilum
Dense Hilum Sign:
superimposition of
another abnormal
density (pneumonia or a
mass ) in the lung or
mediastinum that
projects over the hilum
on the frontal image.
Here is increased density and
enlargement of the right hilum with
a multilobular contour. The CT
scans show enlarged mediastinal
and right hilar lymph nodes.
67. Chest X-ray Abnormalities - The lung hilum
Dense Hilum Sign:
On the frontal (PA) image, the left hilum (red arrow)
appears denser than the right hilum (white arrow). This
may be caused by a hilar mass, but not necessarily. The
lateral view shows airspace disease (pneumonia) in the
superior segment of the left lower lobe (yellow arrow).
68. Chest X-ray Abnormalities - lung fields
Lung abnormalities:
Abnormal whiteness
(increased density):
Consolidation
Atelectasis
Nodule or mass
Interstitial
Abnormal blackness
(decreased density):
Cavity
Cyst
Emphysema
Assess the lungs by comparing the upper,
middle and lower lung zones on the left
and right
69. Chest X-ray Abnormalities - lung fields
Four patterns of
increased density:
Consolidation
Lobar
Diffuse
Multifocal ill-
defined
Atelectasis
Nodule or mass
Solitary Pulmonary
Nodule
Multiple Masses
Interstitial
Reticular
Fine Nodular
72. lung field abnormalities - Consolidation
The key-findings on the
Ill-defined
homogeneous opacity
obscuring vessels
Silhouette sign: loss of
lung/soft tissue
interface
Air-bronchogram
Extention to the pleura
or fissure, but not
crossing it
No volume loss
May be Blunting of
costophrenic angle
X-ray are:
73. lung field abnormalities - Consolidation
Air bronchogram refers to the phenomenon of air-filled
bronchi (dark) being made visible by the opacification of
surrounding alveoli (grey/white).
82. lung field abnormalities - Consolidation
Lymphoma: Imaging Findings:
Mediastinal widening due to
mediastinal lymphadenopathy
Parenchymal lung involvement:
Multiple nodules
Consolidation with an
air - bronchogram
Segmental or lobar
atelectasis
Pleural effusions (Mostly
small, unilateral, and
exudative)
Destructive rib or vertebral
body lesion
Chest X-ray reveals multiple
scattered consolidation lesions
involving both lungs
83. lung field abnormalities - Consolidation
Tuberculosis (TB): Primary pulmonary tuberculosis:
Imaging Findings:
Patchy or lobar consolidation
Cavitation (uncommon)
Caseating granuloma
(tuberculoma) which usually
calcifies (known as a Ghon
lesion)
Ipsilateral hilar and
mediastinal (paratracheal)
lymphadenopathy, usually
right sided.
Calcification of nodes
Atelectasis
Pleural effusions
Chest X-ray shows right upper lobe
and left midzone consolidation
and adenopathy.
84. Consolidation - Tuberculosis
Post-primary pulmonary: Imaging Findings:
Almost always affect:
1. Posterior segments of the
upper lobes
2. Superior segments of the
lower lobes
Patchy consolidation
Poorly defined linear and
nodular opacities
Cavitation, Aspergillomas,
fibrosis and Bronchiectasis
pleural effusion
Hilar nodal enlargement
Lobar consolidation,
tuberculoma and miliary TB
Patchy bilateral opacification of the
upper lung lobes with cavitation most
marked on the left (arrow)
85. Consolidation - Tuberculosis
Tuberculoma and Miliary Tuberculosis: Imaging Findings:
Tuberculoma and miliary
tuberculosis are rare
Miliary deposits are seen
both in primary and post-
primary tuberculosis. It
appear as 1-3 mm diameter
nodules, which are uniform in
size and uniformly distributed
Tuberculomas are usually
found as single nodules and
they may include a cavity or a
calcification with sharp
margins. They are usually
found in the upper lobes
Miliary Tuberculosis
86. lung field abnormalities - Consolidation
Aspergillomas:
Mass-like fungus balls of Aspergillus fumigatus, occur in patients
with normal immunity but with pre-existing cavities:
pulmonary tuberculosis
pulmonary sarcoidosis
bronchiectasis
bronchogenic cyst
pulmonary sequestration
Pneumocystis pneumonia (PCP)
associated pneumatocoeles
Imaging Findings: Air crescent sign :
Rounded or ovoid soft tissue attenuating
masses located in a surrounding cavity
and outlined by a crescent of air.
Differential diagnosis (DD); hydatid cyst,
bronchogenic carcinoma and PCP.
Rounded density with an
air crescent
88. lung field abnormalities - Consolidation
Aspiration Pneumonitis and Pneumonia: Imaging Findings:
Chest x-ray shows an infiltrate,
frequently in the superior or
posterior basal segments of a
lower lobe or the posterior
segment of an upper lobe (The
right lower lobe is the most
frequent location).
Multifocal patchy infiltrates
Bilateral perihilar, ill-defined,
alveolar consolidations and
aspiration-related lung abscess
Interstitial or nodular
infiltrates, pleural effusion
Typically localized pneumonia in
the right lower lobe.
89. Consolidation - Lung infarction
Hampton’s Hump: consists of a pleural based
shallow, wedge-shaped consolidation in the lung
periphery with the base against the pleural surface
90. lung field abnormalities - Consolidation
Klebsiella pneumonia (Friedländer’s pneumonia):
Imaging Findings:
Usually involves one of
the upper lobes
Homogeneous,
nonsegmental, lobar
consolidation
Bulging Fissure Sign:
bulging of usually minor
fissure from heavy,
exudate ( arrow)
Lung abscess (es)
Pleural effusion (70%)
and/or empyema
92. Consolidation - Cardiogenic pulmonary edema
Stage I CHF – Redistribution:
Redistribution of the pulmonary veins. This is know as
cephalization (blue arrow) because the pulmonary veins
of the superior zone dilate due to increased pressure.
An increase in width of the vascular pedicle (red arrows)
93. Consolidation - Cardiogenic pulmonary edema
The vascular pedicle is bordered on the right by the
superior vena cava and on the left by the left subclavian
artery origin
94. Consolidation - Cardiogenic pulmonary edema
Stage II CHF - Interstitial edema Characterized by:
1. Kerley’s A lines: extend radially from the hilum to the
upper lobes; represent thickening of the interlobular
septa that contain lymphatic connections.
95. Consolidation - Cardiogenic pulmonary edema
2. Kerley’s B lines: are short horizontal lines situated
perpendicularly to the pleural surface at the lung base;
they represent edema of the interlobular septa.
96. Consolidation - Cardiogenic pulmonary edema
3. Thickening of the bronchial walls (peribronchial cuffing)
and as loss of definition of these vessels (perihilar haze).
97. Consolidation - Cardiogenic pulmonary edema
4. Fluid in the major or minor fissure (shown here)
produces thickening of the fissure beyond the pencil-
point thickness it can normally attain
98. Consolidation - Cardiogenic pulmonary edema
Stage III CHF - Alveolar edema Characterized by:
Alveolar edema with
perihilar consolidations
and air bronchograms
( Bat's wing or butterfly
pulmonary opacities )
(yellow arrows)
Pleural fluid (blue arrow)
Prominent azygos vein
and increased width of
the vascular pedicle (red
arrow)
An enlarged cardiac silhouette (arrow heads).
99. lung field abnormalities - Consolidation
Bat's wing appearance:
A bilateral perihilar distribution of consolidation.
Reverse bat's wing appearance:
Peripheral or subpleural consolidation
100. lung field abnormalities - Consolidation
Reverse bat's wing appearance
In Chronic eosinophilic pneumonia
101. lung field abnormalities - Consolidation
Adult Respiratory Distress Syndrome ( ARDS )
ARDS versus Congestive Heart Failure:
Diffuse bilateral
patchy infiltrates
More uniform
opacification
Homogenously
distributed
No cardiomegaly
No cephalization
Usually no pleural
effusion or Kerley
B lines
102. lung field abnormalities - Consolidation
Pneumonia can be classified histologically into lobar, lobular,
bronchopneumonia, and interstitial.
Bronchopneumonia characterised by:
Multiple small nodular
or reticulonodular
opacities which tend to
be patchy and/or
confluent.
The distribution is often
bilateral and
asymmetric, and
predominantly involves
the lung bases
103. lung field abnormalities - Consolidation
Atypical pneumonia (AP) characterised by:
Patchy reticular or reticulonodular opacities
Subsegmental and sometimes segmental atelectasis
Seen in the perihilar lung.
(AP) Legionella pneumonia:
Multifocal and bilateral patchy
infiltrate
Middle and lower zone
predominance
Pleural effusions can be common
Associated hilar adenopathy
may be present.
Cavitation and a mass-like
appearance
Legionella pneumonia.
Chest radiograph shows
dense consolidation in
both lower lobes.
104. lung field abnormalities - Consolidation
(AP) Mycoplasma pneumonia characterised by:
Peribronchial and perivascular interstitial infiltrates.
Reticular densities most common
Airspace consolidation.
Reticulonodular
opacification
Nodular or mass-like
opacification
Bilateral peribronchial
perivascular interstitial
infiltrates
Common Lower lobes
affection
Mycoplasma pneumonia .The chest
radiograph shows patchy non-
segmental opacities bilaterally.
105. lung field abnormalities - Consolidation
(AP) Chlamydia pneumonia characterised by:
Alveolar infiltrates or bronchopneumonia
Findings are often limited to a single lobe
lower lobe involvement
occurring more frequently
Up to 25% of patients may
have a small to moderate-
sized pleural effusion
Interstitial pneumonia is rare
Hilar or mediastinal
lymphadenopathy is
uncommon
Chlamydia pneumonia .
Consolidation within the superior
segment of the left lower lobe.
106. lung field abnormalities - Consolidation
(AP) Viral pneumonia characterised by:
Patchy, unilateral, or bilateral:
consolidations and
ground-glass opacity or
poorly defined centrilobular
nodules.
Peribronchial thickening
Areas of atelectasis or
air trapping
Pleural effusion, hilar
lymphadenopathy and
pneumothorax are
uncommon findings. Respiratory syncytial virus
(RSV). Bilateral upper zone
patchy airspace opacification.
107. lung field abnormalities - Consolidation
(AP) Covid-19 pneumonia characterised by:
Normal in up to 63% in the early stages
Ground glass (68.5%), coarse horizontal linear opacities, and
consolidation. These are more likely to be peripheral and in
the lower zones
Bilateral lung involvement is
most common
Pleural effusion is rare (3%)
Covid-19 pneumonia. ground glass
opacity in both mid and lower zones of
the lungs, which is predominantly
peripheral (white arrows) with
preservation of lung marking. Linear
opacity can be seen in the periphery of
the left mid zone (black arrow)
108. lung field abnormalities - Consolidation
(AP) Fungal Pneumonia
characterised by:
Patchy infiltrate, nodules,
consolidation, cavitation,
or pleural effusion may be
observed.
Mediastinal adenopathy is
common in endemic fungal
pneumonias.
The adenopathy may be
either unilateral or bilateral.
Miliary infiltration occurs in
patients with disseminated
disease.
Fungal Pneumonia . multiple
pulmonary nodules
109. lung field abnormalities - Consolidation
E-Cigarette or Vaping Product-Associated Lung Injury:
Bilateral lower-lobe predominant hazy (ground glass) and
consolidative opacities
Rarely:
Pleural effusion
Pneumothorax
pneumomediastinum
E-cigarette or
Vaping-product
associated lung injury,
showing significant
bilateral alveolar opacities
110. lung field abnormalities - Consolidation
Wegener's granulomatosis characterized by:
Nodules or mass lesions, which may cavitate
Fleeting focal infiltrates (lung consolidation )
111. lung field abnormalities - Consolidation
It is a congenital abnormality. A
nonfunctioning part of the lung lacks
communication with the bronchial
tree and receives arterial blood
supply from the systemic circulation.
The plain X-ray often shows a
triangular or oval-shaped, basal,
posterior lung mass, or, less
commonly, as a cyst more on the left
An infected sequestration may be
associated with a parapneumonic
effusion, and may contain one or
more fluid levels.
Pulmonary sequestration: This is an uncommon cause of lobar
consolidation.
Chest radiograph showing left
lower lobe consolidation
(arrow)
112. lung field abnormalities - Consolidation
Eosinophilic pneumonia (EP):
Acute EP : A pattern consistent
with pulmonary edema, with
extensive airspace opacity,
interlobular septal thickening (ie,
Kerley B-lines), and pleural
effusions. The infiltrates are
diffuse and not peripherally
based.
Chronic EP : Nonsegmental
peripheral airspace consolidation
(“photographic negative shadow
of pulmonary oedema” - reverse
bat wing appearance) involving
mainly the upper lobes .
Chronic EP: The chest x-ray
shows bilateral peripheral
patchy infiltrates with relative
sparing of the lower lobes.
113. lung field abnormalities - Consolidation
Septic emboli:
Usually present as
multiple ill-defined
densities, which are
probably
consolidations.
In about 50%
cavitation is seen.
114. lung field abnormalities - Interstitial disease
On a CXR the most common pattern is reticular.
The ground-glass pattern is frequently not detected.
The cystic pattern is also difficult to appreciate.
High-resolution computed tomography (HRCT) has the ability
to better define diseases that have similar CXR patterns.
There are many causes. For example:
116. lung field abnormalities - Alveolar vs. Interstitial
Alveolar = air sacs
Radiolucent
Can contain blood,
mucous, tumor, or
edema (“airless lung”)
Interstitial = vessels,
lymphatics, bronchi, and
connective tissue
Radiodense
Interstitial disease:
prominent lung markings
with aerated lungs
117. lung field abnormalities - Interstitial disease
Linear Pattern:
There is thickening of the
interlobular septa (contain
pulmonary veins and
lymphatics ), producing
Kerley lines.
DD of Kerly Lines:
( Pulmonary edema is the
most common cause, Mitral
stenosis, Lymphangitic
carcinomatosis, Malignant
lymphoma, Congenital
lymphangiectasia, Idiopathic
pulmonary fibrosis, Pneumoconiosis and Sarcoidosis )
118. lung field abnormalities - Interstitial disease
Reticular Pattern:
Fine "ground-glass" (1-2
mm): e.g. interstitial
pulmonary oedema
Medium "honeycombing"
(3-10 mm): commonly seen
in pulmonary fibrosis
Coarse (> 10 mm): cystic
Spaces caused by
parenchymal destruction,
e.g. usual interstitial
pneumonia, pulmonary
sarcoidosis, pulmonary
Langerhans cell histiocytosis
120. lung field abnormalities - Interstitial disease
Nodular pattern:
A nodular pattern consists
of multiple round
opacities, generally
ranging in diameter from
1 mm to 1 cm
Nodular opacities may be:
Miliary nodules: <2 mm
Pulmonary
micronodule: 2-7 mm
Pulmonary nodule:
7-30 mm
Pulmonary mass:
>30mm
123. lung field abnormalities - Interstitial disease
A reticulonodular
pattern results from a
combination of reticular
and nodular opacities.
A differential diagnosis
should be developed
based on the
predominant pattern.
If there is no
predominant pattern,
causes of both nodular
and reticular patterns
should be considered.
Causes: the same disorders as reticular patterns
Reticulonodular pattern:
124. lung field abnormalities - Interstitial disease
Ground-glass appearance
A hazy area of increased
attenuation in the lung with
preserved bronchial and
vascular markings.
Aetiology:
Normal expiration
Partial filling of air spaces
Partial collapse of alveoli
Interstitial thickening
Inflammation
Oedema
Fibrosis
Neoplasm
Perihilar ground-glass
appearance in the shape of
bats-wings
125. lung field abnormalities - Interstitial disease
A lung cyst:
an air filled structure and occurs without associated pulmonary
emphysema with perceptible wall typically 1 mm in thickness but can
be up to 4 mm. The diameter of a lung cyst is usually < 1 cm.
Aetiology:
Sjogren syndrome
light chain deposition disease
Amyloidosis
Others:
Birt-Hogg-Dubé syndrome
Pulmonary trauma
Congenital cystic lung disease
(congenital pulmonary airway
malformation, pulmonary
sequestration, bronchogenic cyst)
Tracheobronchial papillomatosis
Hydatid Cyst
Interstitial disease:
Pulmonary Langerhans cell
histiocytosis
lymphangioleiomyomatosis with
or without tuberous sclerosis
Interstitial pneumonia (DIP, LIP)
Pneumatocele
Sarcoidosis
Neurofibromatosis
Cystic bronchiectasis
PCP
Honeycombing in UIP
126. lung field abnormalities - Interstitial disease
Hypersensitivity pneumonitis (HP) - (acute & Subacute):
PCX-ray may be normal
PCX-ray commonly shows
a bilateral diffuse micro nodular
infiltrate, usually dense towards
hila, have a predilection for the
midzones or lower zones. An
irregular and linear infiltrate
may be present in lower zones.
Acute severe attack : a pattern
of diffuse airspace disease or a
ground-glass pattern mimicking
that of pulmonary edema or,
more rarely, as consolidation.
Bilateral reticulonodular
interstitial infiltration
secondary to subacute
hypersensitivity pneumonitis.
127. lung field abnormalities - Interstitial disease
Hypersensitivity pneumonitis (HP) - (chronic):
Pulmonary fibrosis affects
upper zones predominantly,
loss of lung volume.
Reticular pattern and
honeycombing, more severe
in the upper lobes than in
the lower ones
Larger ring shadows 1-4 mm
in diameter are due to bullae,
blebs, cysts, or bronchiectasis.
Parallel line shadows are
caused by bronchiectasis or
bronchial wall thickening
Chronic HP. Diffuse reticular pattern, more
severe in the upper lobes with a decrease
of lung volume. Note also the ground glass
opacity present in the inferior lobes,
especially on the left inferior
128. lung field abnormalities - Interstitial disease
Sarcoidosis; classified by chest x-ray into 5 stages :
Stage 0: normal chest
radiograph
Stage I: hilar or
mediastinal nodal
enlargement only
Stage II: nodal
enlargement and
parenchymal disease
Stage III: parenchymal
disease only
Stage IV: end-stage
lung (pulmonary
fibrosis)
129. lung field abnormalities - Interstitial disease
Radiographic varieties of Sarcoidosis :
Hilar and mediastinal lymphadenopathy: Garland triad, also known
as the 1-2-3 sign is bilateral hilar and right paratracheal
lymphadenopathy.
Dystrophic calcification of involved lymph nodes: Calcification can
be amorphous, punctate, popcorn like, or eggshell.
Parenchymal changes: including fine nodular; reticulonodular;
acinar (poorly marginated, small to large nodules or coalescent
opacities); and, rarely, focal (solitary nodule or mass).
Mycetomas: in stage IV sarcoidosis and apical bullous disease
In stage IV : when fibrosis supervenes, hilar retraction, decreased
lung volume, and honeycomb lung may be present. Bullous disease,
air trapping and diaphragmatic tenting may also be seen.
Pulmonary hypertension may develop: Prominent main pulmonary
artery, enlarged right and left pulmonary arteries, right ventricular
enlargement, and attenuation of peripheral vessels.
130. lung field abnormalities - Interstitial disease
Can be even normal in patients
with very early disease
In advanced disease:
Decreased lung volumes
Basal fine to coarse
reticulation due to more
extensive involvement of the
lower lobes
Honeycomb Lung and traction
bronchiectasis
The major fissure is shifted
inferiorly which is best seen on
the lateral chest radiograph.
Usual interstitial pneumonia (UIP):
Plain film features are nonspecific
Usual interstitial pneumonia
(UIP). X- ray show reticular
opacities with apibasal gradient
131. lung field abnormalities - Interstitial disease
Usual interstitial pneumonia (UIP):
Honeycombing:
Chest radiograph demonstrates coarse
bibasilar reticular interstitial disease
(honeycomping) (red arrows)
The radiographic appearance
of honeycombing comprises
reticular densities caused by
the thick walls of the cysts.
Honeycomping
132. lung field abnormalities - Interstitial disease
Bronchiectasis:
CXR may be normal
Volume loss
Increased pulmonary markings
Indistinct vessel margins due
to peribronchial fibrosis.
Tram lines: dilated and thickened
airways
Ring shadows: thickened and
abnormally dilated bronchial walls
Clusters of cysts in Cystic type
Dextrocardia (Immotile cilia
syndrome)
Mucus plugging (finger-in-glove)
appearance
Atelectasis or diffuse lung fibrosis
Tram-Track sign
133. lung field abnormalities - Interstitial disease
Bronchiectasis:
Cystic bronchiectasis with
multiple cystic airspaces
Ring shadow ( red arrow) & Tram
lines ( yellow arrow)
134. lung field abnormalities - Interstitial disease
Bronchiectasis: Location:
Allergic bronchopulmonary
aspergillosis – central
Childhood viral infections –
Lower lobe predominance
Mounier-Kuhn syndrome –
First to fourth order bronchi
Mycobacterial avium complex
- Right middle lobe and lingual
Primary ciliary dyskinesia –
Fifty percent associated with
situs inversus, middle lobe,
and lingular predominance
Cystic fibrosis - Upper lobe,
particularly right upper lobe
Postprimary mycobacterial
tuberculosis (traction
bronchiectasis) – Apical
and posterior segments of
upper lobes
Sarcoidosis (traction
bronchiectasis) – Upper
lobe predominance
Usual interstitial
pneumonitis (commonest
cause of traction
bronchiectasis) - Lower
lobe predominance, worse
peripherally
135. lung field abnormalities - Interstitial disease
Allergic bronchopulmonary aspergillosis (ABPA):
Early in the disease : normal
CXR, or only demonstrate
changes of asthma.
Fleeting shadows of
transient pulmonary
infiltrates represent
eosinophilic pneumonia.
Eventually, bronchiectasis
may be evident.
Mucoid impaction in dilated
bronchi can appear mass-
like or sausage-shaped or
branching opacities (finger
in glove sign).
Pulmonary collapse.
"Glove like" opacity in the right upper
zone (yellow dotted line) represents
sputum plugged bronchiectasis
136. lung field abnormalities - Interstitial disease
Pneumocystis Carinii Pneumonia (PCP) - CXR findings:
Bilateral, diffuse, often perihilar
finely granular / reticular interstitial
airspace infiltrates.
Isolated lobar or focal consolidation,
particularly with an upper-lobe
predominance
Cavitation
Cystic lung disease and spontaneous
pneumothorax.
Miliary nodularity, bronchiectasis,
endobronchial lesions
Pleural effusion and hilar
lymphadenopathy are uncommon
CXR may be normal
Typical bilateral air-space
consolidation of PCP in
acquired immunodeficiency
virus infection.
137. lung field abnormalities - Interstitial disease
Lymphangitic carcinomatosis:
The term given to tumour spread
through the lymphatics of the lung,
and is most commonly seen
secondary to adenocarcinoma e.g.
breast cancer, bronchogenic
adenocarcinoma, colon cancer,
stomach cancer, prostate cancer,
cervical cancer, thyroid cancer, etc.
CXR may be normal or Appears as
reticular or reticulonodular
opacification, often with associated
septal lines (Kerley A and B lines),
peribronchial cuffing, pleural
effusions, and mediastinal and/or
hilar lymphadenopathy
Lymphangitic carcinomatosis.
The radiograph
like in the case of interstitial
pulmonary oedema
138. lung field abnormalities - Interstitial disease
Silicosis:
1. Acute silicosis (silicoproteinosis):
Large bilateral perihiliar consolidation
or ground glass opacities.
2. Chronic simple silicosis
(common type ): CXR shows multiple
nodular opacities:
Well-defined and uniform in shape
and attenuation
From 1 to 10 mm in diameter
Predominantly located in the upper
lobe and posterior portion of the lung
Nodules may Calcify
Lymph node enlargement common:
Eggshell calcification of hilar nodes
(5%), DD: Sarcoidosis
Silicosis features a diffuse
micronodular lung disease
with an upper lobe
predominance
139. Interstitial disease - Silicosis
3. Complicated silicosis
(progressive massive fibrosis
(PMF), or conglomerate
silicosis): CXR shows large
symmetric bilateral opacities
that are:
1 cm or more in diameter and
with an irregular margin
Usually in mid-zone or
periphery of upper lobes
Compensatory emphysema
occurs in lower lung fields.
Progressive Massive Fibrosis
(PMF) with scarring and
retraction of hila upwards.
Progressive Massive Fibrosis. There are
conglomerate soft-tissue densities in
both upper lobes (black arrows) with
linear scarring leading from the lower
lobes (white arrows).
140. Interstitial disease - Silicosis
4.Complicated silicosis : Complicated
by tuberculous (Silicotuberculosis),
non-tuberculous mycobacterial,
and fungal infection, certain
autoimmune diseases, and lung
cancer.
Eggshell node calcification in silicosis
Silicotuberculosis, with bilateral
conglomerate disease. Several
cavities are present in the left upper
lobe
141. lung field abnormalities - Atelectasis
CXR show direct and indirect signs of lobar collapse:
Direct signs include displacement of fissures and opacification of
the collapsed lobe.
Indirect signs include the following:
Displacement of the hilum
Mediastinal shift toward the side of collapse
Loss of volume in the ipsilateral hemithorax
Elevation of the ipsilateral diaphragm
Crowding of the ribs
Compensatory hyperlucency of the remaining lobes
Silhouetting of the diaphragm or heart border
Atelectasis can be sub-categorized by morphology as follows:
linear (plate, band, discoid, subsegmental) atelectasis
lobar atelectasis
segmental and subsegmental atelectasis
round atelectasis
142. lung field abnormalities – Atelectasis
Complete atelectasis: Characterized by:
Opacification of the entire hemithorax
An ipsilateral shift of the mediastinum.
143. lung field abnormalities - Atelectasis
Increased density in the upper medial
aspect of the right hemithorax
Elevation of the horizontal fissure
Loss of the normal right medial
cardiomediastinal contour
Elevation of the right hilum
Hyperinflation of the right middle and
lower lobe result in increased
translucency of the mid and lower
parts of the right lung
Right diaphragmatic tenting
Non-specific signs :
Elevation of the hemidiaphragm
Crowding of the right sided ribs
Shift of the mediastinum and trachea to the right
Lobar atelectasis: Right upper lobe collapse:
144. Atelectasis - Lobar atelectasis
Right upper lobe collapse: The Golden S-sign (or reverse
S-sign of Golden): is seen on
PA view and the appearance
is that of right upper lobar
collapse with a central mass
expanding the hilum.
On the lateral projection it is
harder to identify. Elevation
of the horizontal fissure and
upper part of the oblique
fissure may be visible.
145. Atelectasis - Lobar atelectasis
Right middle lobe collapse:
On lateral projection, right
middle lobe collapse is
usually relatively easy to
identify,
Appearing as a triangular
opacity in the anterior
aspect of the chest overlying
the cardiac shadow.
The horizontal fissure is
displaced inferiorly and the
inferior part of the oblique
fissure, displaced
anterosuperiorly.
146. Atelectasis - Lobar atelectasis
Right middle lobe collapse:
On frontal CXR, the findings are more
subtle:
The normal horizontal fissure is no
longer visible (as it rotates down)
Blurring of the right heart border
(silhouette sign) (in atelectasis as
well as consolidation)
Non-specific signs may be subtle or
absent due to the small size of the
right middle lobe :
Elevation of the hemidiaphragm
Crowding of the right sided ribs
Shift of the mediastinum to the right
linear opacities in the lobe suggest that the collapse is chronic
(right middle lobe syndrome), with associated bronchiectasis.
147. Atelectasis - Lobar atelectasis
Right lower lobe collapse:
On frontal CXR, the findings :
Increased opacity (triangular in
shape) at the medial base of the
right lung
Obliteration of the silhouette of
the right hemidiaphragm
The right hilum is depressed
Descending right lower lobe
pulmonary artery is not visualized
Right heart border maintained.
Non-specific signs :
Elevation of the hemidiaphragm
Crowding of the right sided ribs
Shift of the mediastinum to right
The collapsed right lower lobe
is a triangular opacity (orange
arrows).The right
hemidiaphragmatic outline is
lost (blue dashed line).
148. Atelectasis - Lobar atelectasis
Right lower lobe collapse:
On lateral projection:
The right
hemidiaphragmatic
outline is lost posteriorly
The lower thoracic
vertebrae appear denser
than normal (they are
usually more radiolucent
than the upper
vertebrae) The collapsed right lower lobe a
triangular opacity (orange arrows).
The right hemidiaphragmatic
outline is lost (blue dashed line).
149. Atelectasis - Lobar atelectasis
Left upper lobe collapse:
Hazy or 'Veil-like' opacification of
the left hemithorax
Right heart border not visible
The left hemidiaphragm is still
visible
Near-horizontal course of the left
main bronchus
The luftsichel sign (next)
Elevation of the hemidiaphragm
Non-specific signs :
'peaked' or 'tented‘
hemidiaphragm: juxtaphrenic peak
sign
Crowding of the left sided ribs
Shift of the mediastinum to the left
Left upper lobe collapse: Notice
the ovoid density at the left
hilum, CT confirmed a large left
hilar mass, which occluded the
left upper lobe bronchus
150. Atelectasis - Lobar atelectasis
Left upper lobe collapse:
The luftsichel sign:
In some cases the
hyperexpanded superior
segment of the left lower
lobe insinuates itself
between the left upper
lobe and the superior
mediastinum, sharply
silhouetting the aortic
arch and resulting in a
lucency medially ( red
arrow ).
151. Atelectasis - Lobar atelectasis
Left upper lobe collapse:
On lateral projections:
Increase in the
retrosternal opacity.
left lower lobe is
hyperexpanded and
the oblique fissure
displaced anteriorly
(arrows).
152. Lobar Atelectasis - Left upper lobe collapse
Lingular collapse:
The lingula collapses inferiorly and medially
This produces an opacity in contact with the left heart border,
which causes loss of the normal silhouette
Lingular collapse. (A) Frontal view of isolated collapse of the lingular
segments of the left upper lobe showing loss of clarity of the left
heart border and a raised hemidiaphragm. (B) The similarity to a right
middle lobe collapse can be appreciated on the lateral view.
153. Atelectasis - Lobar atelectasis
Left lower lobe collapse:
1. Triangular opacity in the
posteromedial aspect of left lung
2. Edge of collapsed lung may
create a 'double cardiac contour'
3. left hilum will be depressed
4. loss of the normal left
hemidaphgragmatic outline
5. loss of the outline of the
descending aorta
6. Non-specific signs :
Elevation of the hemidiaphragm
Crowding of the left sided ribs
Shift of the mediastinum to left
154. Atelectasis - Lobar atelectasis
Left lower lobe collapse:
7. The flat waist sign refers to flattening
of the contours of the aortic arch and
adjacent main pulmonary artery. It is
seen in severe left lower lobe collapse
and is caused by leftward
displacement and rotation of the
heart.
8. On lateral projection:
The left hemidiaphragmatic outline
is lost posteriorly
The lower thoracic vertebrae appear
denser than normal (they are usually
more radiolucent than the upper
vertebrae)
155. lung field abnormalities - Atelectasis
Rounded atelectasis:
Classically associated with
asbestos exposure
It is typically found in lower
lung lobes, particularly in
posterior regions
Has the form of peripheral
round, oval or fusiform lesion
of diffuse outline.
The size of the lesion ranges
from 2.5 to 8 cm.
Pleural thickening at the level
of atelectasis is typical.
The volume of the affected
lobe is reduced
Posteroanterior chest radiography:
peripheral, well-defined opacity (round
atelectasis).
156. lung field abnormalities - Atelectasis
Segmental atelectasis:
Collapse of one or several
segments of a lung lobe.
It is a morphological subtype
of lung atelectasis.
It is better appreciated on CT
and Its radiographic
appearance can range from
being a thin linear to a wedge
shaped opacity then does not
abut an interlobar fissure.
Plain radiograph: shows a band-
like opacity with well-defined
borders, perpendicular to costal
surface, located in the left upper
lobe.
157. lung field abnormalities - Atelectasis
Plate-like atelectasis due to poor inspiration in a
patient who had abdominal surgery
Plate-like/subsegmental atelectasis:
Seen in smokers, elderly, after abdominal surgery, patients in the
ICU and in pulmonary embolism
linear shadows of increased density at the lung bases, usually
horizontal, measure 1-3 mm in thickness and are only a few cm long
158. lung field abnormalities - Atelectasis
Cicacitration atelectasis:
Atelectasis can be the result of fibrosis of lung tissue.
Seen after radiotherapy and in chronic infection, especially TB.
Atelectasis of the right upper lobe as a result of TB. Notice the
deviation of the trachea. There is also some atelectasis of the left
upper lobe, which results in a high position of the left pulmonary
artery as seen on the lateral view (red arrow)
159. lung field abnormalities - Nodules and Masses
A solitary pulmonary nodule:
Defined as a discrete, well-marginated, rounded opacity less than or
equal to 3 cm in diameter that is completely surrounded by lung
parenchyma, does not touch the hilum or mediastinum, and is not
associated with adenopathy, atelectasis, or pleural effusion.
161. lung field abnormalities - Nodules and Masses
Other causes :
Hyperdense pulmonary mass:
(a pulmonary mass with internal
calcification)
Cavitating pulmonary mass:
(gas-filled areas of the lung in
the center of the mass. They are
typically thick walled and their
walls must be greater than 2-5
mm. They may be filled with air
as well as fluid and may also
demonstrate air-fluid levels).
A Pulmonary mass:
It is an area of pulmonary opacification that measures more than
3 cm. The commonest cause for a pulmonary mass is lung cancer.
162. lung field abnormalities - Nodules and Masses
Hyperdense pulmonary mass:
They include:
Granuloma: most common
Pulmonary hamartoma
Bronchogenic carcinoma
Bronchogenic cyst
Carcinoid tumours
Pulmonary metastases
Dystrophic calcification:
Papillary thyroid carcinoma
Giant cell tumour of bone
Synovial sarcoma
Bone forming / cartilage
mineralisation:
Osteosarcoma
Chondrosarcoma
A solitary well marginated
homogeneous radiodensity is seen in
the right upper zone with focal central
area of increased density within.
163. lung field abnormalities - Cavities
Pulmonary cavities :
Are gas-filled areas of
the lung in the center
of a nodule, mass or
area of consolidation.
They are typically thick
walled and their walls
must be greater than
2-5 mm.
They may be filled with
air as well as fluid and
may also demonstrate
air-fluid levels.
165. lung field abnormalities - Cavities
Multicystic mass with air in cysts
CXR in type I ( large (2-10 cm)
cysts ) and II (small (< 2 cm)
cysts) CCAM may demonstrate a
multicystic (air-filled) lesion.
Type III ( microcysts ) CCAM
appear solid.
Large lesions may cause mass
effect with resultant, mediastinal
shift, and depression and even
inversion of the diaphragm.
The cysts may be completely or
partially fluid filled, in which case
the lesion may appear solid or
with air fluid levels.
Congenital cystic adenomatoid malformation (CCAM):
Multiloculated cystic lesion in
right hemithorax with marked
mediastinal shift to the left.
166. lung field abnormalities - Cavities
It can be pulmonary 10-15% or
Mediastinal 65-90%
Usually in the medial 1/3 of lungs
With a lower lobe predilection
Mediastinal cysts are visualized as
a mediastinal mass (image 1)
Intrapulmonary cysts usually present
as a solitary pulmonary nodule unless
the cyst contains air.
Cysts are usually fluid filled,
occasionally a communication may
develop following infection or
intervention, resulting in an air-filled
cystic +/- an air-fluid level (image 2)
Bronchogenic cyst: During development a portion of the tracheo-
bronchial tree gets separated. CXR :
167. lung field abnormalities - Decreased density
Unilateral hypertranslucent hemithorax: potential causes:
Pulmonary (ventilation)
Pulmonary emphysema
Congenital lobar overinflation
Unilateral bullus/bullae
Compensatory hyperinflation
Airway obstruction e.g.
bronchial compression and
endobronchial obstruction
Swyer-James-MacLeod
syndrome
Unilateral lung transplant
Pleura and pleural space
Pneumothorax
Pleural effusion (contralateral)
Rotation:
Poor patient positioning
Scoliosis
Chest wall defect
Mastectomy
Poland syndrome (absent
pectoralis major muscle)
Mediastinal
Mediastinal fibrosis
Vascular (perfusion)
Pulmonary embolism i.e.
Westermark sign
Congenital heart disease
Unilateral absence of pulmonary
artery or hypoplasia or stenosis
Shunt (e.g. Blalock-Taussig)
168. lung field abnormalities - Decreased density
Pulmonary emphysema:
1. Hyperinflation
Flattened hemidiaphragm (s):
most reliable sign
Increased and usually irregular
radiolucency of the lungs
Increased retrosternal airspace
Increased antero-posterior
diameter
Sternal bowing
Obtuse costophrenic angle on
posteroanterior or lateral film.
Widely spaced ribs
A narrow mediastinum
Low flattened diaphragm
169. lung field abnormalities - Decreased density
Pulmonary emphysema:
2. Vascular changes
Paucity of blood vessels,
often distorted
Pulmonary arterial
hypertension:
Prominence of the
pulmonary hilum and
enlargement of the main
pulmonary arteries.
Right ventricular
enlargement: encroachment
into the retrosternal space on
a lateral chest film
Pruning of peripheral vessels
170. Decreased density - Pulmonary emphysema
Flat diaphragm are
present when the
maximum
perpendicular height
(red line) from the
superior border of the
diaphragm to a line
drawn between the
costophrenic and
cardiophrenic angles in
PA view or between
the costophrenic and
sternophrenic angles in
lateral view (blue line)
is less than 1.5 cm.
171. lung field abnormalities - Decreased density
Air within pulmonary interstitium &
lymphatics
New bubbly linear, oval, or spherical
cystic lucencies within lung of intubated
premature infant
Small interstitial lucencies > > large
focal/multifocal cysts
Affected segment is often
hyperexpanded
Precursor to pneumothorax or
pneumomediastinum
Pulmonary Interstitial emphysema (PIE ):
A, CXR shows asymmetric bubblelike,
nonbranching lucencies within the left lung
consistent with PIE. B, The child developed a
tension pneumothorax on subsequent exam.
172. Pleural disease - Pneumothorax
Pneumothorax:
Rotation of CXR can obscure a
pneumothorax . Rotation can
also mimic a mediastinal shift.
A linear shadow of visceral
pleura with lack of lung markings
peripheral to it indicates
collapsed lung
Flattening or inversion of the
diaphragm on the affected side
Mediastinal shift toward the
contralateral side
In erect patients: Pleural gas
collects over the apex .
173. Pleural disease - Pneumothorax
In the supine position:
The juxtacardiac area, the
lateral chest wall, and the
subpulmonic region are the best
areas to search for evidence of
pneumothorax.
The deep sulcus sign: (very wide
and deep costophrenic angle)
An ipsilateral increased lucency
in the upper quadrant of the
abdomen.
Double Diaphragm Sign: both
the diaphragmatic dome and
anterior portions of the
diaphragm are visualized
174. Pleural disease - Pneumothorax
Double Diaphragm Sign
of Pneumothorax. Air in
the right hemithorax
displaces both the
dome (white arrow)
and the anterior
costophrenic angle
(yellow arrow) in this
patient with a large,
right-sided
pneumothorax. There is
also a deep sulcus sign
present (red arrow).
175. Pleural disease - Pneumothorax
large pneumothorax if:
the vertical distance between
the lung and thoracic cage at
the apex > 3cm
or the distance between the
lateral lung edge and chest
wall at the level of the hilum
> 2cm
lateral decubitus studies:
Should be done with the
suspected side up
The lung will then 'fall' away
from the chest wall
Rib films are indicated
This chest X-ray shows a large
pneumothorax (P) which is >2 cm
depth at the level of the hilum.
176. Pleural disease - Pneumothorax
A bulla or thin wall cyst can be
mistaken for loculated
pneumothorax. The pleural
line caused by pneumothorax is
usually bowed at its center
towards lateral chest wall but
the inner margins of bulla or
cyst is generally concave rather
than convex.
Pneumothorax with pleural
adhesion may simulate bulla or
lung cyst. Differential diagnosis
by comparison with previous
chest radiography, lateral
decubitous or CT scanning
A chest radiograph shows
Right bullous formation
177. Pleural disease - Pneumothorax
A skin fold can be mistaken for a pneumothorax. Unlike
pneumothorax, skin folds usually continue beyond the chest
wall, and lung markings can be seen beyond the apparent
pleural line.
178. Pleural disease - Pneumothorax
Deep sulcus sign (red arrow) in a supine patient in the ICU.
The pneumothorax is subpulmonic.
179. Pleural disease - Pneumothorax
Hydropneumothorax:
With the patient
upright, there will be
an air-fluid level in the
thoracic cavity
On supine radiographs,
a hydropneumothorax
will be more difficult
to see although a
uniform grayness to
the entire hemithorax
with the absence of
vascular markings
suggest the diagnosis
180. Pleural disease - Pleural thickening
Best seen at the lung edges where the pleura runs tangentially to
the x-ray beam. Causes:
Unilateral pleural thickening:
• Peripheral shadowing on the right
• Loss of right lung volume
• Shadowing over the whole right
lung due to circumferential pleural
thickening
Benign pleural thickening
Recurrent inflammation
Following a pleural empyema
Complication of haemothorax
Asbestosis & silicosis
Recurrent pneumothoraces
Malignant pleural thickening
Primary pleural malignancy
• Mesothelioma
• Primary pleural lymphoma
Pleural metastases
Secondary pleural lymphoma
181. Pleural disease - Apical pleural cap
In normal asymptomatic individuals, the apical cap is an irregular
density generally less than 5 mm high located over the apex of the
lung.
Apical pleural cap (yellow arrows)
Causes:
Pleural thickening/scarring
Idiopathic: common
feature of advancing age
Secondary to tuberculosis
Radiation fibrosis
Pancoast tumour
Haematoma
Lymphoma
Abscess
Metastases
182. Pleural disease - Pleural plaques
Asbestos related pleural plaques:
Calcified pleural plaques with irregular
thickened nodular edges resembling holly
leaf. Costophrenic angles and apices are
spared
Most pleural plaques are
multiple, bilateral, and often
symmetrical and are located
in the mid-portion of the chest
wall between the seventh and
tenth ribs. they follows rib
contour and diaphragm.
Plaques may be calcified (they
are irregular, well-defined,
and classically said to look like
holly leaves), however, most
(85-95%) are not
Visceral pleura, lung apices,
and costophrenic angles are
typically spared.
183. Pleural disease - Pleural effusion
Pleural effusion is an abnormal
collection of fluid in the pleural space.
Fluid may be (Transudate, Exudate,
Pus, Blood, Chyle, Cholesterol, Urine )
A. Erect frontal Chest X-ray:
1. Blunting of costophrenic angle
2. Blunting of cardiophrenic angle
3. The diaphragmatic contour is
partially or completely obliterated,
depending on the amount of the
fluid (silhouette sign).
4. Fluid within the horizontal or
oblique fissures
5. Concave meniscus seen laterally and
gently sloping medially (horizontal
in case of hydropneumothorax)
184. Pleural effusion - Erect frontal Chest X-ray
6. Massive pleural effusion:
Opacification of entire hemithorax
(“white-out” lung) and shifting of
mediastinum to the opposite side
(note: The mediastinal shift can be
less prominent or even absent in
the presence of underlying lung
collapse or contralateral
hemithorax abnormality)
Around 5-7 liters of pleural fluid
Generally, the pleural effusion is
said to be massive if it crosses the
anterior border of the 2nd rib. It is
said to be moderate if it crosses
the anterior border of the 4nd rib
and is said to be mild or small if it
is below that.
Massive right pleural effusion
(1), with shift of mediastinum
towards left (2)
185. Pleural effusion - Erect frontal Chest X-ray
7. Lamellar effusion:
linear opacification
paralleling the lateral
aspect of lung.
It is a shallow collection
between lung surface
and visceral pleural
sometimes sparing the
costophrenic angle.
It represent interstial
pulmonary fluid.
Chest radiograph showing an encysted pleural
effusion (lenticular shaped opacity) along the
right oblique fissure (asterisk), a right sided
lamellar pleural effusion (arrow), and left
subpulmonic effusion (line)
186. Pleural effusion - Erect frontal Chest X-ray
8. Subpulmonic effusion:
Unilateral subpulmonary effusion is
more common on right side.
Left: The distance between the lung
and the stomach bubble will exceed
2 cm (double red arrow)
Right: appear as a raised diaphragm
with flattening and lateral
displacement of the dome.
187. Pleural effusion - Erect frontal Chest X-ray
9. Loculated (encysted, encapsulated) pleural effusion:
Loculation secondary to
adhesions after an
infected or hemorrhagic
effusion.
Peripheral soft-tissue
opacity with smooth
obtuse tapering margins
Pleural opacity.
Encapsulated pleural
effusion – Frontal chest
radiograph; shows a
lenticular opacity with
smooth borders and obtuse
angles (black arrows)
188. Pleural effusion - Erect frontal Chest X-ray
10. Encysted (encapsulated) pleural effusion in the fissure:
Loculated effusion in the fissures
appears as a well-defined
elliptical opacity with pointed
margins.
Pseudotumor/vanishing tumor
(phantom tumor): Loculated
effusion in the fissures ,
secondary to congestive heart
failure, hypoalbuminemia, renal
insufficiency or pleuritis.
Radiologically simulating a
neoplasm. It disappears rapidly in
response to the treatment of the
underlying disorder (red arrow)
189. Pleural disease - Pleural effusion
B. Lateral Chest X-ray:
Small effusions appear as a
dependent opacity with
posterior upward sloping of
a meniscus-shaped contour.
The opacity obliterates the
underlying portion of the
diaphragmatic contour
(silhouette sign).
Can detect an effusion as
small as 50–75 mL
Note the concave meniscus
blunting posterior costophrenic
angle.
190. Pleural disease - Pleural effusion
C. Supine Chest X-ray:
Due to the effect of gravity, the
pleural fluid is distributed
throughout the posterior part of
the pleura during supine
position – this cause the
hemithorax to appear whiter or
paler grey compared to the
normal side.
Vessels are often visible through
the shadowing.
It is therefore especially difficult
to identify similar sized bilateral
effusions as the density of the
lungs will be similar.
Requires about 200 ml fluid
Right-sided effusion. a veil-like
increased density of the lower right
hemithorax (blue arrow). Note that the
pulmonary vascular structures are not
obscured or silhouetted by the vague
density but, rather, are still visible
through it (open arrow).
191. Pleural disease - Pleural effusion
D. lateral decubitus Chest X-ray:
A small amount of fluid (10-25 mL) can be depicted on this
projection.
The layering fluid can easily be detected as a dependent, sharply
defined, linear opacity separating the lung from the parietal
pleural and chest wall
The parietal pleura–chest wall margin can be identified as a line
connecting the inner apices of the curvature of the ribs.
A : There will be lateral
displacement of the
dome of right
hemidiaphragm ( arrow )
B : Right lateral decubitus
view shows the pleural
fluid gravitating to
dependent right pleural
space ( arrows )
192. Pleural disease - Pleural effusion
Complete white-out of a hemithorax:
Trachea pulled toward the opacified
side:
Pneumonectomy
Total lung collapse
Pulmonary agenesis
Pulmonary hypoplasia
Trachea remains central in position:
Consolidation
Pulmonary oedema/ARDS
Pleural mass: e.g. mesothelioma
Chest wall mass: e.g. Ewing sarcoma
Pushed away from the opacified side:
Pleural effusion
Diaphragmatic hernia
Large pulmonary mass
193. Pleural disease - Pleural effusion
How do you determine the etiology of effusion from chest x-ray?
Bilateral: consider transudative effusions first. You will need
clinical information.
Bilateral effusions with cardiomegaly: Congestive heart failure
Bilateral pleural effusions associated with ascites in a alcoholic:
Cirrhosis
Unilateral: most of them are exudative
Massive unilateral effusion: Malignancy
Pleural effusion with apical infiltrates: Tuberculosis
Pleural effusion with nodes or mass or lytic bone lesions:
Malignancy
Loculated effusions are empyemas
Pleural effusion with a missing breast suggesting resection for
cancer: Malignancy
Pleural effusion following chest trauma: Hemothorax
In patients with mediastinal lymphoma: Chylothorax
194. Chest X-ray Abnormalities- Costophrenic angle
Costophrenic (CP) angle blunting:
On a frontal CXR the costophrenic angles should form acute angles
which are sharp to a point.
Often the term costophrenic "blunting" is used to refer to the
presence of a pleural effusion. This, however, is not always correct
and costophrenic angle blunting can be related to other pleural
disease, underlying lung disease or Lung hyper-expansion.
1- left CP
angle blunting
in effusion
2- bilateral CP
angles
blunting in
emphysema
195. Elevated hemidiaphragm: If the left hemidiaphragm is higher
than the right or the right is higher than the left by more than 3 cm
Can result from:
Above the diaphragm
Decreased lung volume
Atelectasis/collapse
Lobectomy/pneumonectomy
Pulmonary hypoplasia
Diaphragm
Phrenic nerve palsy
Diaphragmatic eventration
Contralateral stroke: usually middle cerebral artery distribution
Below the diaphragm
Abdominal tumour, e.g. liver metastases or primary malignancy
Subphrenic abscess
Distended stomach or colon
Chest X-ray Abnormalities - Diaphragm
198. Diaphragmatic hernia: defect in the diaphragm can result
from:
Congenital:
Bochdalek hernia: most common, More frequent on left
side, located posteriorly and usually present in infancy
Morgagni hernia: smaller, anterior and presents later,
through the sternocostal angles
Acquired:
Traumatic diaphragmatic rupture
Hiatus hernia
Iatrogenic
Chest X-ray Abnormalities - Diaphragm
199. Morgagni hernia
are: Anteromedial
parasternal defect,
small, Usually
unilateral, more
often right-sided
(90%)
Chest X-ray Abnormalities - Diaphragm
Bochdalek Hernia : Frontal
view of the chest shows a
large air-containing and
walled structure in the region
of the left lower lobe (white
arrow). It is originating from
below the diaphragm. The air-
containing structure is seen
posteriorly on the lateral view
(red arrow).
200. Hiatus hernias occur when there is herniation abdominal contents
through the oesophageal hiatus of the diaphragm into the thoracic
cavity. Appears as retrocardiac opacity with air-fluid level
Chest X-ray Abnormalities - Diaphragm
Posteroanterior (PA) and lateral view of hiatal hernia.
Can you see the air-filled "mass" posterior to the heart
201. Free gas under diaphragm (Pneumoperitoneum): It is a
finding in the chest X-ray seen in case of perforation of
hollow viscus.
Chest X-ray Abnormalities - Diaphragm
CXR shows Minor
opacity in the left
lower zone. Large
volume of free
subdiaphragmatic
gas ( yellow arrow).
202. Chest X-ray Abnormalities - Diaphragm
Chilaiditi syndrome: is a rare condition in which a portion of the
colon is abnormally located (interposed) in between the liver and the
diaphragm. It is one of the causes of pseudopneumoperitoneum.
Features that suggest a Chilaiditi syndrome (i.e. Chilaiditi sign):
Gas between liver and diaphragm
Rugal folds within the gas suggesting that it is within the bowel.
203. Cardiophrenic angle lesions:
The more common:
Pericardial fat pad
Pericardial cyst
Morgagni's hernia
Lymphadenopathy:
metastases , lymphoma
Pericardial fat necrosis
Pericardial lipomatosis
Other less common:
Thymoma
Hydatid cyst
Right middle lobe collapse
Chest X-ray Abnormalities - Diaphragm
Pericardial
cyst: X-ray
shows a well
circumscribed
mass in
contact with
right cardiac
margin.
204. Cardiomegaly and heart failure:
The heart is enlarged if the cardiothoracic ratio (CTR) is greater than
50% on a PA view. If the heart is enlarged, check for other signs of
heart failure such as pulmonary oedema, septal lines (or Kerley B
lines), and pleural effusions.
Chest X-ray Abnormalities - Heart
CXR shows:
• Cardiomegaly CTR = 18/30 (>50%)
• Upper zone vessel enlargement (1)
- a sign of pulmonary venous
hypertension
• Pulmonary oedema (2) - bilateral
increased lung markings (classically
peri-hilar and shaped like bats wings
- more widespread in this case)
• Septal (Kerley B) lines (3)
• Pleural effusions (4)
205. left atrial enlargement:
The double density sign: Right side of
the dilated left atrium is visible next to
the right heart border (right atrium). It
may extend out beyond the right heart
border, an appearance known as atrial
escape.
Oblique measurement of greater than
7cm (blue arrow).
Convex left atrial appendage; produces
“straightening” of the left heart border
- normally it is flat or concave.
Splaying of the carina to greater than a
90 degree angle (yellow lines).
Posterior displacement of the left main
stem bronchus on lateral radiographs
resulting to the "walking man" sign.
Chest X-ray Abnormalities - Heart
206. left atrial enlargement:
The "walking man" sign: right and left bronchi, therefore, do not overlap,
but rather form an upside down 'V', sometimes referred to as the walking
man sign
Posterior displacement of a barium-filled esophagus or nasogastric tube
Chest X-ray Abnormalities - Heart
Annotated lateral radiograph shows the markedly dilated left
atrium displacing the left main bronchus posteriorly resulting to the
"walking man" sign
207. left ventricular enlargement: CXR shows:
Left heart border is displaced leftward, inferiorly, or posteriorly
Rounding of the cardiac apex
The aorta is prominent
Lateral view: Retrocardiac space become narrowed or disappeared,
esophageal space disappeaered
Chest X-ray Abnormalities - Heart
208. Chest X-ray Abnormalities - Heart
If we draw a tangent line from
the apex of the left ventricle to
the aortic knob (red line) and
measure along a perpendicular
to that tangent line (green line)
The distance between the
tangent and the main
pulmonary artery (between
two small green arrows) falls
in a range between 0 mm
(touching the tangent line) to
as much as 15 mm away from
the tangent line
left heart border:
209. Chest X-ray Abnormalities - Heart
left heart border abnormalities:
1. The main pulmonary artery may
project beyond the tangent line
(greater than 0 mm). This can occur if
there is increased pressure or
increased flow in the pulmonary
circuit.
2. The main pulmonary artery may
project more than 15 mm away from
the tangent line. This can occur in
left ventricle enlargement and/or
aortic knob enlargement e.g.
atherosclerosis, aortic
incompetence, and mitral
incompetence.
210. Right atrial enlargement: Features are non-specific but include :
Right heart enlargement (the right atrium and ventricle cannot be
separately identified on a radiograph) causes filling-in of the
retrosternal clear space and prominence of the right heart border
A prominently convex lower right heart border
Enlarged, globular heart
Narrow vascular pedicle
Chest X-ray Abnormalities - Heart
211. Right ventricular enlargement: :
Frontal view demonstrates:
Rounded left heart border
Uplifted cardiac apex
Chest X-ray Abnormalities - Heart
CXR showing right
ventricular
hypertrophy (arrows,
note filling of the
retrosternal space by
an enlarged right
ventricle in the lateral
view) and enlarged
central pulmonary
arteries (arrowhead).
Lateral view demonstrates:
Filling of the retrosternal
space
Rotation of the heart
posteriorly
212. Pulmonary embolism (PE): Features include:
Normal CXR
Plate atelectasis
Hampton hump: pleural-based
opacity (pulmonary infarction)
Small pleural effusion
Elevated hemidiaphragm
Fleischner’s sign (prominent
amputated pulmonary artery)
Westermark’s sign (peripheral
oligaemia)
Palla's sign: Enlarged right descending pulmonary artery
The more abnormal the CXR, the less likely is Pulmonary embolism
Normal CXR in a breathless hypoxic person in the absence of
bronchospasm means that Pulmonary embolism is likely
Chest X-ray Abnormalities - Heart
213. Heart- Pulmonary embolism
A chest radiograph shows a
Westermark sign (arrow), with a
focal area of oligemia in the right
middle zone and cutoff of the
pulmonary artery in the upper
lobe of the right lung.
Fleischner sign: Refers to the
prominence of central pulmonary
artery caused either by pulmonary
hypertension that develops secondary
to PE or by distension of the vessel by
a large clot
214. Pulmonary Arterial Hypertension: Features include:
Elevated cardiac apex due to right ventricular hypertrophy
Enlarged right atrium
Prominent pulmonary outflow tract
Enlarged pulmonary arteries
Pruning of peripheral pulmonary vessels
Chest X-ray Abnormalities - Heart
215. Ventricular aneurysm:
A ventricular aneurysm is usually the sequel to a myocardial
infarct, thus cases of calcified ventricular aneurysm are
rare.
Typically the left cardiac border changes shape and bulges.
Chest X-ray Abnormalities - Heart
216. Ventricular
Pseudoaneurysm:
It is caused by a
contained
rupture of the LV
free wall.
A chest
radiograph may
show
cardiomegaly
with an abnormal
bulge on the
cardiac border.
Chest X-ray Abnormalities - Heart
217. Pericardial effusion:
It occurs when excess fluid collects in
the pericardial space (a normal
pericardial sac contains approximately
30-50 mL of fluid).
CXR Suggestive but not usually
diagnostic.
Globular enlargement of the cardiac
shadow giving a water bottle
configuration
Widening of the subcarinal angle
without other evidence of left atrial
enlargement may be an indirect clue
Chest X-ray Abnormalities - Heart
218. Pericardial effusion:
lateral CXR may show:
Loss of retrosternal clear space
A vertical opaque line
Produced by pericardial fluid
(yellow arrows) separating a
vertical lucent line directly
behind sternum Produced by
epicardial fat (white arrows)
anteriorly from a similar lucent
vertical lucent line Produced by
pericardial fat (red arrows)
posteriorly; this is known as
the Oreo cookie sign
Chest X-ray Abnormalities - Heart
Real
Oreo
cookies
219. Transposition of the great arteries (TGA) (also known as transposition
of the great vessels (TGV)):
The classic appearance described as an egg on a string sign
Most common cyanotic congenital heart lesion
The aorta arises from the morphologic right ventricle and the
pulmonary artery arises from the morphologic left ventricle
Narrowing of the superior mediastinum on radiographs
Patent ASD, VSD, Foramen ovale, systemic collaterals to sustain life
The right atrial border is convex, and the left atrium is enlarged
CXR Abnormalities - Congenital heart disease
220. Total Anomalous Pulmonary Venous Return:
Occurs when the pulmonary veins fail to drain into the left atrium
and instead form an aberrant connection with some other
cardiovascular structure
2% of cardiac malformations
SNOWMAN SIGN: resembles a snowman
CXR Abnormalities - Congenital heart disease
221. Partial Anomalous Pulmonary Venous Return:
Scimitar syndrome
Anomalous pulmonary vein drains any or all of the lobes of the
right lung, and empties into the inferior vena cava, portal vein,
hepatic vein, or right atrium
Vein appears like a scimitar, a sword with a curved blade that
traditionally was used by Persian and Turkish warriors.
Hypoplasia of right lung, hypoplasia of right pulmonary artery, and
anomalous arterial supply of the right lower lobe from abdominal
aorta.
CXR Abnormalities - Congenital heart disease
222. Tetralogy of Fallot:
10%–11% of cases of congenital heart disease
Components: Ventricular septal defect, Infundibular pulmonary
stenosis, Overriding aorta, Right ventricular hypertrophy
Blood flow to the lungs is usually reduced
The heart has the shape of a wooden shoe or boot (in French,
coeur en sabot)
CXR Abnormalities - Congenital heart disease
223. Aortic Coarctation:
5%–10% of congenital cardiac lesions
Eccentric narrowing of the lumen of aorta at the level where the
ductus or ligamentum arteriosus inserts anteromedially
Classic radiologic signs:
Figure of 3 sign: contour abnormality of the aorta
Reverse figure of three sign is observed on the left anterior
oblique view during barium esophagography
Inferior rib notching: Roesler sign on CXR pathognomonic
CXR Abnormalities - Congenital heart disease
Left anterior oblique view
224. Mediastinal abnormalities - Mediastinal widening
Superior mediastinum:
Should have a width less than 8 cm
on a PA CXR.
A widened mediastinum can be
associated with:
Anteroposterior CXR view
Unfolded aortic arch
(not pathological) or a thoracic
aortic aneurysm
Mediastinal masses
Oesophageal dilatation
Ruptured aorta
Mediastinal lipomatosis:
increased deposition of normal
unencapsulated fat
Unfolded aorta: widened and
'opened up' appearance of
the aortic arch. It is seen with
increasing age
225. Mediastinal abnormalities - Aortic Dissection
Aortic Dissection: CXR
findings include:
1. Mediastinal widening; it is
noted in 60% of patients
2. Irregularity of the aortic
contour
3. Double aortic contour
4. Double-calcium sign:
Inward displacement of
atherosclerotic calcification
by more than 10 mm
5. Pleural effusion (more
common on the left side;
suggests leakage)
CXR shows; double density
aortic arch (yellow/red arrows),
Mediastinal widening, and
Cardiac enlargement
226. Mediastinal abnormalities - Aortic Dissection
6. Tracheal displacement
to the right
7. Pericardial effusion
8. Cardiac enlargement
9. Displacement of a
nasogastric tube
10. Left apical pleural
capping (opacity) due to
secondary mediastinal
hematoma
11. Normal CXR in 12% of
patients
Aortic Dissection: rightward deviation of the
trachea (red arrow); left apical pleural capping
(blue arrow); aortic “double-calcium” sign
(between white arrows); depression of the left
bronchus (purple arrow); pleural effusion
(green arrow); widened mediastinum and loss
of the aorto-pulmonary window (not labeled).
227. Mediastinal abnormalities - Pneumomediastinum
Radiographic features of Pneumomediastinum:
Small amounts of air appear as linear or curvilinear lucencies outlining
mediastinal contours and form:
1. Pneumoprecardium: where air enters the pericardial cavity
2. Subcutaneous emphysema
Pneumo-precardium. Plain posterior-anterior (PA)
and lateral chest radiograph shows the presence
of air (arrow) between the pleura and left border
(PA) and anterior (lateral) of the heart
subcutaneous emphysema
228. Mediastinal abnormalities - Pneumomediastinum
3. air around pulmonary artery and main branches: ring around
artery sign
4. air outlining major aortic branches: tubular artery sign
Tubular Artery Sign (Red arrows)
Ring around artery sign
229. Mediastinal abnormalities - Pneumomediastinum
5. Continuous diaphragm sign: due to air trapped posterior to
pericardium
6. Spinnaker Sail Sign (angel wing sign) is seen on neonatal
postero-anterior CXR when thymic lobes are displaced laterally
by air, (Very typical sign in neonatal age).
Spinnaker Sail Sign (angel wing sign)
Continuous diaphragm sign
230. Mediastinal abnormalities - Pneumomediastinum
Naclerio V sign:
It is seen as a V-shaped air collection. One limb of the V is produced
by mediastinal air outlining the left lower lateral
mediastinal border. The other limb is produced by air between the
parietal pleura and medial left hemidiaphragm.
Lateral Chest X-Ray
Retrosternal air
Lateral Decubitus Chest X-Ray
Air will not move with change in position
Neck Films
Air outlining fascial planes of the neck
Naclerio V sign
231. Mediastinal abnormalities - Masses
Clues to locate mass to mediastinum
Masses in the lungMediastinal masses
May contain air
bronchograms
A lung mass abutts
the mediastinal
surface and creates
with lung an acute
angles.
Not contain air bronchograms
The margins with the lung will be obtuse.
Mediastinal lines (azygoesophageal recess,
anterior and posterior junction lines) will be
disrupted.
There can be associated spinal, costal or
sternal abnormalities.
LEFT: A lung mass abutts the
mediastinal surface and creates
acute angles with the lung.
RIGHT: A mediastinal mass will
sit in the mediastinum, creating
obtuse angles with the lung.
232. Mediastinal abnormalities - Masses
Clues to locate mass to mediastinum:
LEFT: there is a lesion that has an acute border
with the mediastinum. This must be a lung mass.
RIGHT: shows a lesion with an obtuse angle to the
mediastinum. This must be a mediastinal mass.
Localize mass within the mediastinum
In lateral CXR, mediastinum is divided into superior and Inferior.
Inferior mediastinum is divided into anterior, middle, and posterior
233. Mediastinal abnormalities - Masses
Anterior Mediastinal Masses (5Ts)
Thymus Abnormalities (thymoma, invasive thymoma, thymic carcinoma,
thymolipoma/thymoliposarcoma, thymic cyst, thymic hyperplasia, thymic
carcinoid)
Thyroid (thyroid neoplasms, thyroid goiter)
Terrible Mediastinal Lymphoma (Hodgkin and non-Hodgkin lymphoma)
Germ Cell Tumors (Teratoma, teratocarcinoma, seminoma, choriocarcinoma,
embryonal cell carcinoma, endodermal sinus tumors (yolk sac tumors))
Thoracic Aortic Aneurysm
Pericardial Cyst
Morgagni Hernia
Sternal Tumors
Pericardial Fat Pad
B-cell lymphoma. (A) a very large
mass (arrows). (B) The mass in the
anterior mediastinum (outlined in
yellow) is displacing the trachea
(blue lines) posteriorly.