chest_imaging

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Chest imaging
in
pneumoconiosis
NOTE
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In young persons or in asymptomatic patients a
PA projection alone is generally used as a
screening procedure.
A lateral film should be obtained whenever chest
disease is suspected and in screening
examination of patients 40 years of age or older
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Male or female? Look for the presence of breast
shadows (this will help you to notice a mastectomy
too).
Good inspiration? The diaphragms should lie at the
level of the sixth ribs anteriorly. The right
hemidiaphragm is usually higher than the left because
the liver pushes it up
Good penetration? You should just be able to see the
lower thoracic vertebral bodies through the heart
Is the patient rotated? The spinous processes of the
thoracic vertebrae should be midway between the
medial ends of the clavicles.
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PA films are better, particularly because the heart is not
as magnified as on an AP film, making it easier to
comment on the heart size.
First look at the mediastinal contours - run your eye
down the left side of the patient and then up the right.
The trachea should be central. The aortic arch is the
first structure on the left, followed by the left
pulmonary artery; notice how you can trace the
pulmonary artery branches fanning out through the
lung
Two thirds of the heart lies on the left side of the
chest, with one third on the right. The heart should take
up no more than half of the thoracic cavity. The left
border of the heart is made up by the left atrium and
left ventricle.
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The right border is made up by the right atrium
alone (the right ventricle sits anteriorly and
therefore does not have a border on the PA
chest x ray film - a question that examiners love
to ask. Above the right heart border lies the
edge of the superior vena cava.
The pulmonary arteries and main bronchi arise
at the left and right hila. Enlarged lymph nodes
can also occur here, as can primary tumours.
These make the hilum seem bulky
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Now look at the lungs. Apart from the
pulmonary vessels (arteries and veins), they
should be black (because they are full of air).
. Force your eye to look at the periphery of the
lungs - you should not see many lung markings
here; if you do then there may be disease of the
air spaces or interstitium.
Make sure you can see the surface of the
hemidiaphragms curving downwards, and that
the costophrenic and cardiophrenic angles are
not blunted - suggesting an effusion. Check
there is no free air under the hemidiaphragm
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Finally look at the soft tissues and bones. Are both
breast shadows present? Is there a rib fracture? This
would make you look even harder for a pneumothorax.
Are the bones destroyed or sclerotic?
There are only two spaces to look at on the later- al
film.
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The heart lies antero-inferiorly. Look at the area anterior and
superior to the heart. This should be black, because it
contains aerated lung. Similarly the area posterior to the heart
should be black right down to the hemidiaphragms. The
blackness in these two areas should be equivalent; therefore
you can compare one with the other. If the area anterior and
superior to the heart is opacified, suspect disease in the
anterior mediastinum or upper lobes. If the area posterior to
the heart is opacified suspect collapse or consolidation in the
lower lobes.
normal
Pneumoconiosis
(Lung Dust)

Refers to the pulmonary manifestations of
exposure to a variety of dusts or aerosols
 Silicosis
 Coal workers pneumoconiosis
 Asbestosis
 Berylliosis
 Siderosis
CXRPneumocon iosis- based on
ILO classification standards
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The accepted means of quantifying dust exposure and retention-very
important in evaluating disability claims
Profusion of opacities categorized as 1, 2, or 3 with a second subclassification to indicate degree of certainty (1, 0/0, 0/1; 1/0, 1/1, 1/2,
etc.,)
Size
 Rounded/regular; p <1.5 mm , q 1.5-3 mm, or r >3 to 10 mm (these
are more specific for dust exposure)
 Irregular opacities; s, t, or u based on the same sizes
 Larger opacities are classified as A (1-5 cm), B (>5 cm), or C
(equivalent to the entire RUL zone)
 Progression of disease is usually associated with a change in
profusion, and not size of opacities
Presence/degree of pleural thickening classified as A (<5 mm), B (5-10
mm), C (>10 mm)
silicosis
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Silica: active dusts .fibrogenic
Silicosis has a progressive nature despite cessation
of dust exposure
X-ray picture is of multiple small rounded opacities
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Usually in the upper lobes
May occasionally calcify (20%)
Lymph node enlargement is common
Large opacities are conglomerations of small opacities
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Progressive Massive Fibrosis (PMF)
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Cavitate from tuberculosis or ischemic necrosis
Massive fibrosis and conglomerate mass formation in upper
lobes with scarring and retraction of hila upwards
Eggshell calcification of hilar nodes in 5%
Caplan’s syndrome consists of large necrobiotic
nodules superimposed on silicosis
Silicosis predisposes to TB
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The radiologic findings of tuberculosis developed in the
patients with silicosis include pleural effusion, newlydeveloped consolidation, bronchovascular infiltrations,
cavitary change in pre-existing PMF, etc.
C.W.P
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Coal dusts: A combination of active and inert material
Coal dust is deposited in the alveolar macrophages
which migrate to, and leave, coal dust deposits around
the respiratory bronchiole
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Here a very small fibrous reaction occurs
Complicated CWP occurs as large masses in either
the upper lobes or the superior segments of the lower
lobes
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Unlike silicosis, the large upper lobe lesions of CWP are
single (rather than conglomerate) black masses with a liquid
core, not a fibrous tissue core
The masses may undergo cavitation either from
TB or ischemia
 The rounded opacities of CWP, found
predominantly in the upper lobes
 Massive fibrosis are round or oval and tend to
migrate toward the hila creating peripheral areas
of emphysema and bulla.
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Asbestosis
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Asbestos particles invoke a hemorrhagic response in
the lung
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Fibers are then coated with a ferritin-like material resulting in
ferruginous bodies
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Does its damage in respiratory bronchioles and alveoli
Affects lower lobes first
Opacities are small and irregularly shaped
Cardiac silhouette may become shaggy
Almost all patients have some pleural involvementpleural plaque, diffuse pleural thickening, calcification
or effusion
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Pleural involvement without parenchymal
disease is common
Parietal pleural plaques in the mid lung are the
most common asbestos-related disorder and are
usually bilateral
Pleural calcification occurs in about 50% with
asbestos-related disease, especially diaphragmatic
pleura
Diffuse pleural thickening involves
diaphragmatic pleura, blunting of costophrenic
sulci and lateral chest wall thickening
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Effusion alone may occur early in the disease
(first 20 years) in about 3% of cases
Asbestos-related lung cancer is either
squamous cell or adenocarcinoma
Bronchogenic ca is almost always associated
with cigarette smoking
In contrast to silicosis, hilar lymph nodes are
rarely affected
HRCT:thickend interlobular septal
lines,curvilinear subpleural lines,parenchymal
bands and honycombing.
Asbestos and Cigarette Smoking Interaction on
Chest X-ray ILO Category
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Asbestos causes pulmonary
fibrosis, while smoking
usually causes emphysema
(destruction of alveolar
surface area).
In those with asbestosis who
have also been heavy
smokers, there is (on average)
an increase in the profusion
of small linear opacities on
chest x-ray.
A smoker may have one half
category higher profusion
than a non-smoker with
equivalent asbestos exposure
Egg shell
PMF(silicosis)
normal
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This picture shows complicated
coal workers pneumoconiosis.
There are diffuse, massive light
areas that run together in the
upper and middle parts of both
lungs. These are superimposed on
a background of small and poorly
distinguishable light areas that are
diffuse and located in both lungs.
Diseases which may explain these
X-ray findings include, but are
not limited to: complicated coal
workers pneumoconiosis (CWP),
silico-tuberculosis, and metastatic
lung cancer
Pneumoconiosis (Radiographic
type p)
normal
Routine torax X-ray(PA and Lateral)
from a 52 yo male assymptomatic
patient with asbestosis
HRCT scan (left) shows thickened intra- and interlobular
lines (A). HRCT (right) shows subpleural curvilinear density.
(B)
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This PA radiograph
shows some of the
typical findings of
asbestosis including a
"shaggy heart", pleural
plaques and diaphragm
calcification
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This picture shows complicated
coal workers pneumoconiosis.
There are diffuse, small, light
areas (3 to 5 mm) in all areas on
both sides of the lungs. There
are large light areas which run
together with poorly defined
borders in the upper areas on
both sides of the lungs. Diseases
which may explain these X-ray
findings include complicated
coal workers pneumoconiosis
(CWP), silico-tuberculosis,
disseminated tuberculosis,
metastatic lung cancer, and other
diffuse infiltrative pulmonary
diseases.
Caplan
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Description: X-ray
showing lung nodules
in a patient with RA
(note differential
diagnosis: Wegener's
granulomatosis,
metastatic cancer (eg
kidney)TB)
Small rounded opacity
Small rounded opacity
caplan
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55 year old man who was pensioned early
from his job as a coal worker.
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Features in the image
There are well defined nodules in both lungs
with a mid-zone predominance. The nodules
appear more confluent in the left upper
zone, where larger ill-defined masses are
present, distorting and elevating the left
hilum. Both hila appear enlarged and
lobulated. Although the overlying nodules
may make the hila look large, the present
appearance suggests hilar lymphadenopathy.
In addition to the slightly prominent basal
segment lower lobe bronchial markings,
there is the appearance of additional
perihilar strands. A horizontal line, crossing
the basal vessels, is probably a linear fibrotic
scar.
DX: Pneumoconiosis,silicosis developing
massive fibrosis not pure anthracosis,which
produces less fibrotic reaction
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This chest X-ray
shows coal workers
pneumoconiosis -.
There are diffuse,
small (2 to 4 mm)
light areas on both
sides of the lungs.
Diseases which may
explain these X-ray
findings include
simple coal workers
pneumoconiosis
(CWP) simple
silicosis, disseminated
tuberculosis,
metastatic lung
cancer, and other
diffuse infiltrative
pulmonary diseases.
Carcinoma brounchus,arising in old
tuberculosis with pleural effusion
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Clinical presentation:
53 year old man working as a heating
engineer/fitter cutting asbestos templates. He
smokes 10 cigarettes a day. There was a history
of tuberculosis treated 25 years earlier.
Recently, he complains of a slowly increasing
pain on the left side of his chest.
Features in the image
The right lung is large volume, but the left lung
has reduced volume. The left hemidiaphragm
silhouette has been lost. There is pleural
shadowing that blunts the left costo-phrenic
angle and extending a 'meniscus' into the left
axilla. There is scattered calcific shadowing at
both lung apices. The upper lobe vessels are
crowded, implying some fibrotic shrinkage of
the upper lobes. On the right side the visible
hilum is drawn up, but the left hilar point is
depressed. A poorly defined soft tissue density
is projected behind the left first rib and another
larger density behind the heart. Calcified pleural
plaques are seen in profile above the right
hemidiaphragm and some are partly obscured
by the pleural shadowing on the left side.
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Elderly male, former pottery maker
There are multiple fairly dense nodules, mostly
in both mid and lower zones. The right hilum
appears bulky with some lobulation lateral to
the main bronchi. This resembles hilar
lymphadenopathy, despite the enlarging effect
that overlying nodules have on the hilar
appearance. There are additional radiating
strands, extending from the right hilum,
perhaps too thick for 'Kerley B' lines, but not
corresponding to dilated bronchi alone. The
vessel count in the left upper lobe is reduced
and there is amorphous calcific shadowing at
the left apex. The left hilum is distorted,
undersized and is associated with a horizontal
strand of fibrosis in the left mid-zone.
Dx:silicosis,with perihilar interstitial shadowing.
Old tuberculosis of the left upper
lobe.possible early bronchiectasis.
Chest X-ray of retired coal miner demonstrates
Coalworker’s Pneumoconiosis with Progressive Massive
Fibrosis
Normal Chest ( X-Ray ILO Category 0/0)
Interaction of Asbestos and Cigarette Smoking to
Increase X-ray Markings (Asbestosis, ILO Category 2/2)
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