Reading Chest X-Ray
By the Name of Allah,
The Most Gracious, The Most Merciful
Reading Chest X-Ray
-This document contains only some CXR findings that you
should be familiar for medicine OSCE .No theoretical material
included . This is just a collection of X-rays that I made during
-I hope it will help you for your exam.
-Macleod’s clinical examination-12th edition
-Davidson’s essentials of medicine
Chest X-Ray Basic knowledge
Normal labeled X-Ray
full of air
color) Fluid or
A chest x-ray can detect:
• Airway enlargement
• Breast shadows
• Bones, e.g. rib fractures
• Cardiac enlargement and changes in the size and shape of the
• Pleural effusions
• Diaphragm, e.g. evidence of free air, indicative of perforation
• Pneumothorax, fibrosis, pleural thickening or plaques
• Extrathoracic tissues
• lung parenchyma being evidence of alveolar filling
• Abnormalities in the major blood vessels such as the Aorta;
• Fluid collection in the lungs caused by heart failure
• Collapse of the lungs
Systemic approach to CXR interpretation
• Pt details & date
Note the pt’s name and date of birth as well as the date and time the CXR was
• Technical Quality
Orientation : Most CXR are taken using a postero-anterior (PA) view , if patients
are too unwell to stand , then an antero-posterior (AP) X-ray will be done with
the X-ray source in front of them & the plate behind them. With AP film the
heart appears magnified relative to PA film.
Posture : If the pt is supine , the distribution of air & fluid is changed & it is
impossible to exclude a pneumothorax , pleural effusion or subdiaphragmatic
Rotation : If the pt is not rotated , the spinous processes of the thoracic vertebrae
will be projected midway between the medial borders of the clavicles.
Penetration : The thoracic vertebral bodies should be just visible behind the
heart. If they cannot be seen at all , the film is under-exposed and will appear
too white. If they can be seen in detail , then the film is over-exposed and will
be too dark.
Inspiration : The right hemidiaphragm should be at the level of the anterior end
of the 6th rib or the posterior end of the 9th – 10th ribs. If more ribs are seen ,
hyperinflation is present.
Field of view : All of the lungs should be visible ; make sure that lung apices and
especially costophrenic angles have not been missed .
Systemic approach to CXR interpretation
Should be central .It might be deviated toward the area of loss of volume (e.g.
Lung collapse) or away from an area of increased pressure (e.g. Tension
A cardiac shadow of >50% of the total thoracic width on a PA film is abnormal &
occurs with ventricular dilatation or pericardial effusion.
The left heart border consist of the left ventricle and left atrium , while the right
heart border is made up of the right atrium . Consolidation in the immediately
adjacent lung blurs the heart borders.
• Lung and pleura are discussed in the next slides
The hemidiaphragms should have a well-defined edges , and the costophrenic and
cardiophrenic angles should be sharp. The right hemidiaphragm is usually
higher due to the liver below.
• Soft tissues and bones
Assess the soft tissues , including breast shadows . Look for surgical emphysema &
free air under the diaphragm . Examine each rib , looking for fractures or
metastatic lesions . Then check clavicles and scapula.
• Review areas
Rechek areas in which abnormalities are commonly missed : lung apices ,
subdiaphragmatic air , behind the cardiac shadow & behind hemidiaphragms .
This film shows a
right sided tension
with right sided
shift. This is a
Failure to place a
right chest tube
return to diminish
and lead to
Right Sided tension pneumothorax Left Sided tension pneumothorax
• Hydropneumothorax : implies presence of both air and fluid in the pleural
space ( i.e. between two layers of pleura. An erect chest x-ray will show
the air fluid level. The horizontal fluid level is usually well defined and
extends across the whole length of hemithorax.
Signs of hydropneumothorax can be remembered by 4 'S'
• Straight line dullness
• Shifting dullness
• Succussion splash
• Sound of coin
with white arrow
point to the
The above three images show a hydropneumothorax in three different views.
The PA, lateral, and right decube reveal a layering out of the air and fluid.
The right decube film demonstrates a right hydropneumothorax.
Note the pleural air/fluid level demonstrated by the horizontal air/fluid interface
• Primary TB
-Calcification in 1ry complex is overall relatively rare.
-Few pts have clinical manifestaions.
• Post-primary TB (TB Reactivation)
-Calcification is usually rarer than in 1ry.
-Limited mainly to the apical & posterior segments of upper lobes & superior
segment of lower lobe.
-Bilateral upper lobe disease is very common.
-Cavitation may result ; Cavity is usually thin walled ,smooth or inner margin with
no air-fluid level.
-Transbronchial spread might occur from one upper lobe to opposite one.
• Miliary TB
- Hematogenous dissemination of bacilli. Fine (1-2mm) lesions “millet seed”
throughout the lung fields.
like a circle )
both lungs is
heads, and the
formation of a
in one of the
In this situation
Cavitary in the
*As the disease
occur from one
upper lobe to
This CXR shows
spread to left
Miliary opacities all over the lungs .
(Not very important)
• The type of pneumonia is sometimes characteristic on chest x-ray:
• Lobar - classically Pneumococcal pneumonia, entire lobe consolidated and
air bronchograms common
• Lobular - often Staphlococcus, multifocal, patchy, sometimes without air
• Interstitial - Viral or Mycoplasma; latter starts perihilar and can become
confluent and/or patchy as disease progresses, no air bronchograms
Aspiration pneumonia - follows gravitational flow of aspirated contents;
impaired consciousness, post anesthesia, common in alcoholics,
debilitated, demented pts; anaerobic (Bacteroides and Fusobacterium)
Diffuse pulmonary infections - community acquired (Mycoplasma, resolves
spontaneoulsy) nosocomial (Pseudomonas, debilitated, mechanical vent
pts, high mortality rate, patchy opacities, cavitation, ill-defined nodular)
immunocompromised host(bacterial, fungal, PCP).
These are PA and lateral films of RML pneumonia (arrows).
Note the indistinct borders, air bronchograms, and silhouetting of the
right heart border.
PA and Lateral films of RUL pneumonia
Interstitial pulmonary fibrosis
• Interstitial pulmonary fibrosis has many causes. The six most
common causes of diffuse interstitial pulmonary fibrosis are
idiopathic (IPF, >50% of cases), collagen vascular disease,
cytotoxic agents and nitrofurantoin, pneumoconioses, radiation,
• Clinically the patient with IPF will present with progressive
exertional dyspnea and a nonproductive cough.
• Radiographically : IPF is associated with hazy "ground glass"
opacification early and volume loss with linear opacities
bilaterally, and honeycomb lung in the late stages.
• IPF carries a poor prognosis with death due to pulmonary failure
usually occurring within 3-6 years of the diagnosis unless lung
transplant is performed.
COPD includes chronic bronchitis , chronic bronchiolitis & Emphysema.
Emphysema is commonly seen on CXR as :
• diffuse hyperinflation with flattening of diaphragms
• increased retrosternal space
• bullae (lucent, air-containing spaces that have no vessels that are not
• enlargement of PA/RV (secondary to chronic hypoxia) an entity also known as
• Hyperinflation and bullae are the best radiographic predictors of
emphysema. However, the radiographic findings correlate poorly with the
patientâs pulmonary function tests.
• CT and HRCT (high resolution CT) has emerged as a technique to evaluate
different types, panlobular, intralobular, paraseptal and for guidance prior to
volume reduction surgery.
• Occasionally the trachea is very narrow in the mediolateral plane in
• In smokers with known emphysema the upper lung zones are commonly more
involved than the lower lobes. This situation is reversed in patients with alpha-
1 anti-trypsin deficiency, where the lower lobes are affected.
Note the small
heart size in
comparison to the
A lateral chest
x-ray of a
Note the barrel
chest and flat
Lung bulla as
seen on CXR in
a person with
Chest X-ray changes are divided into four stages:
• Stage 1: Bihilar lymphadenopathy.(BHL)
• Stage 2: bihilar lymphadenopathy and parenchymal infiltrates.
• Stage 3: parenchymal infiltrates without BHL.
• Stage 4: pulmonary fibrosis ; fibrocystic sarcoidosis typically
with upward hilar retraction, cystic and bullous changes.
• Pericardial effusion causes an enlarged heart shadow that is
often globular shaped (transverse diameter is
• A "fat pad" sign, a soft tissue stripe wider than 2mm between
the epicardial fat and the anterior mediastinal fat can be seen
anterior to the heart on a lateral view.
• Serial films can be helpful in the diagnosis especially if rapid
changes in the size of the heart shadow are observed.
Approximately 400-500 ml of fluid must be in the pericardium
to lead to a detectable change in the size of the heart shadow
on PA CXR.