Chest x-ray

rmg: apr, 2017. @Kijohs KiZZa johN Kijohs

CXR 2- dimensional radiographic image of the heart, lungs, airways, blood vessels and bones in chest region. Why do some structures on a

CXR look “white” others “black” Indications (ACTINO) Check quality of x ray • Rotation • Inspiration • Collimation • Exposure / penetration Have a pattern

Technique Examination is performed by means of the following projections:

• Basic Postero-anterior – erect • Alternative Antero-posterior – erect Antero-posterior – supine Antero-posterior – semi-erect • Supplementary Lateral Postero-anterior – expiration Apices / Lordotic view Lateral – upper anterior region Decubitus with horizontal beam

technique

• Usually erect, PA position • Lateral view may be taken to provide more information on the

pathology seen on a PA radiograph • Supine projection for patients who cant stand or sit or for children /

neonates • Other views are done in special situation to assess pathology in

hidden areas

PA chest • Reproduces the normal state of the

heart and mediastinum

• Air rises to the apical region making it easy to recognize a pneumothorax

• Fluid gravitates producing a meniscus

• Diaphragms are lower showing more of the lung bases and heart size can be accurately assessed

• Its easier to clear the scapulae from the lung fields by moving the shoulders forward

Supine chest • Upper lobe vessels, mediastinum

and the heart appear wide making it hard to assess these structures

• Free air rises anteriorly and its difficult to assess

• Fluid accumulates posteriorly obscuring the lung making it difficult to detect and assess the amount of fluid

Anatomy

• Heart • Mediastinum • Lung hila • Lungs • Pleura • Bones, soft tissue • Upper abdomen • Normal variant

Pattern recognition

• Alveolar consolidation • Interstitial • Lung collapse • Masses

Alveolar consolidation (Homogenous opacities, silhouette sign, air bronchogram)

• Fluid (serous, pus, blood) or solid matter filling up the air space / alveoli

• Alveolar shadowing results • Initially ground glass opacity • May progress to homogenous opacity or patchy fluffy shadows • Air bronchograms may be seen Causes of alveolar shadowing 1. Exudates (fluid rich in proteins and cells) – infections, ARDS, inhalation of toxic gases, pulmonary eosinophilia 2. Transudate (not rich in proteins / cells) high hydrostatic pressure pulmonary edema (cardiac, liver failure) 3. Hemorrhage – trauma, anticoagulants, snake bite 4. Tumor infiltration – bronchogenic carcinoma 5. Others – aspiration pneumonia, Mendelssohn’s syndrome (aspiration of gastric juice during anaesthesia leading

to bronchospasm),near drowning pneumonia, hyaline membrane disease of new borns

Alveolar shadowing patterns

1. Segmental /lobar pneumonia Consolidation limited to lobe or

segment Caused by infection (eg acute

pneumonia), infarction, contusion and alveolar cell carcinoma

o Acute pneumonia can be bacterial, non- bacterial or viral

o Bacterial acute pneumonia Streptococcus pneumonia

(pneumococcus) Staphylococcus aureas Haemophilus influenzae Klebsiella pneumonia Legoniella pneumonia oNon bacterial acute pneumonia Mycoplasia pneumonia Chlamydia Coxiella oViruses Influenza Cold viruses

Acute pneumonia

• Opacity limited by fissure, affected lobe retains volume

• Air bronchogram often • S. pneumonae causes lobar

pneumonia • Rounded opacities with ill

defined margins may be observed especially in children

Pneumococcal pneumonia Tends to give rise to lobar or segmental consolidation, often with an associated pleural effusion To the right: CXR of an adult male with pneumonia confined to the anterior segment of the right upper lobe. Note the inferior demarcation by the minor fissure (white arrows).

Klebsiella pneumonia Klebsiella aeriginosa causes a

similar pneumonia to staphylococcus, favors the upper lobes, with a destructive inflammation, bulging of fissures, abscess formation and subsequent cavitation through fibrous resolution similar to pulmonary TB

Above: CXRs of an adult female taken 6 months apart. On the initial CXR (left) there is a large abscess within the right upper lobe (black arrows vertical up) and bulging of the horizontal fissure (white arrow vertical up). On the subsequent CXR (right) there remains a thick walled cavity (horizontal white arrow) and upward bowing of the minor fissure (black arrow vertical down) indicating

Staphylococcal pneumonia Infection by staphylococcus aureus giving rise to consolidation not necessarily

restricted to lobar or segmental anatomy. Complicated by abscess formation, cavitation, empyema and pneumothoraces

Below: CXRs of an adult female with a staphylococcal pneumonia taken 1 month apart. Note the cavitating consolidation in the left mid zone (Image 1) resolving on treatment (Image2). To the right: A pneumatocele in a patient who had had a staphylococcal pneumonia as a child. Note the thin wall, the entirety of which is visible (white arrows), unlike the wall of a bulla.

Alveolar shadowing patterns

2. Bat’s wing shadowing oAcute causes of bat’s wing Acute pulmonary edema Pneumocystis carinii pneumonia oChronic causes Lymphoma Leukemia Sarcoidosis Alveolar proteinosis Alveolar cell carcinoma

oPulmonary edema Initially upper lobe vessels become

prominent than lower (Antler sign / pulmonary vein cephalization) Interstitial edema appears. Blurring of

the hila vessels esp. the RLL arteries, then Karley A, B and C appears Increasing pulmonary edema lead to

alveolar edema (mid zone patchy consolidation / Bat’s wing appearance) Later fluid accumulation in the

interlobar fissures (phantom tumor) and pleural effusion

Pneumocystis jiroveci pneumonia (PJP)

• Commonly affects immune compromised individuals • Patients present with severe difficulty in breathing • CXR features • In early stages, infiltrates appear interstitial • Later bilateral symmetrical alveolar shadows describing a bat’s wing • Shadows may have a ground glass opacity • Small pneumatoceles or pneumocyst may form and these may measure a

few mm in diameter • Pneumothorax may be a complication due to rapture of a pneumocyst

pcp

Alveolar shadowing patterns

3. The others Alveolar shadows which don’t fit

any of the above description “BEF” • Bronchopneumonia (bacterial/viral) • Eosinophilic pneumonia • Fat embolism

oBronchopneumonia Inflammatory exudates involving

the distal airway and bronchi Pyogenic bacteria (eg

staphylococcus pneumonia), or non pyogenic pneumonia ( eg TB) Similar as in pneumonia, but

there are usually crepitations instead of bronchial breathing on auscultation

Appearance Patchy shadows anywhere in the

lung fields No air bronchograms

Pulmonary tuberculosis

• M. tuberculosis • HIV at much more risk • Previous infection / BCG

vaccination lead to hypersensitivity • Patients with no previous exposure

are not hypersensitive, primary tuberculosis

• Hyper-sensitized patients, secondary tuberculosis

• Changes in immune compromised pts may not follow the trend

oPrimary tuberculosis Initial lesion is an area of

consolidation usually in upper lung zones which are better aerated Associated lymphangitis spreading

centrally to the hilar region Gohn complex (Gohn focus,

lymphangitis, and hilar adenopathy) Area of consolidation may break i. Thru the pleura, -- pleural

effusion ii. Into a bronchus, -- bronchogenic

spread (to the rest of the lung), --wide spred large nodular / patchy shadows

iii. Into a vessel, -- miliary TB

Primary TB. Widened paratracheal stripe / superior mediastinal adenopathy associated pericardial effusion causing loss of normal concavity seen in the left heart border at site of left atrial appendage.

Examples of primary TB

TB conts…

• The disease (primary TB) is usually self-limiting, but resolution takes 6–12 months and residual scarring is common

To the right: CXR of patient one in previous slide, following treatment for PTB. The consolidation has resolved, but residual fibrotic scaring remains in both apices (white arrows)

Post-Primary TB

• Re-infection • Lesions usually start in apical areas as

consolidation which may spread and coalesce, caseate, and cavitate

• There may be one cavity associated with smaller cavities

• Changes may be bilateral although asymmetry

• There may be associated fibrosis indicating an attempt at healing

• Dispersal of infection thru bronchogenic spread to lower / mid zones

• Cavities are potential sites of colonization by aspergillosis, a fungal infection

o CXR appearance Consolidation more in upper lobes,

anterior segment Patchy opacities or nodular ill-defined

shadows Cavities may be noted with fibrosis, with

shift of anatomical structures Tenting and puckering of the pleura and

hemidiaphragm due to fibrosis Cavities have walls of varying thickness

and may have air-fluid levels Air-fluid levels are usually an indication of

activity There may be areas of bronchiectasis or

emphysema Lymphadenopathy is rare except in HIV

patients

Pulmonary TB manifestation

Post primary TB

CXR of an adult male with pulmonary TB. Image 1. Demonstrates a cavitating soft tissue lesion in the right apex, but no lymphadenopathy. Image 2. Was taken following 6 months of treatment. The lesion has almost completely resolved, but a residual cavity and adjacent scarring remain.

Miliary TB

CXRs of an adult male. Image 2 there are small nodules spread throughout the lungs all in the region of 2–3 mm in size. The patient was culture positive for pulmonary TB

Note CXR 1 taken 2 months earlier, when the patient was developing symptoms of pulmonary TB, but there were no signs of this on the CXR.

Interstitial shadowing

• Pathologic changes or in the interstitium (connective tissue between the alveoli in which the blood vessels, lymphatics and nerves pass

• Initial stage, the process spares the alveoli and the bronchioles • Its therefore not homogenous. • Several subtypes of interstitial opacities based on radiographic

appearance i. Reticular opacities ( too many lines), this can create a net-like

appearance ii. Nodular opacities (too many dots / nodules) iii. Reticulonodular pattern (too many lines and dots)

Reticular, Linear, Reticulolinear pattern: Thin lines which may run separately or criss-cross, resulting in woven reticulolinear pattern. Usually fluid, fibrosis or tumor infiltrations in the interstitium Includes Kerley line

Alveolar vs interstitial opacities

nodules

Above: A case of previous chicken pox pneumonia. Note the multiple calcified nodules of varying size, very dense of CXR despite their small size To the left: Frontal CXR demonstrating numerous nodules and masses. These are metastases from seminoma and have clearly fined borders

Lung collapse RUL Collapse

Collapses forward, lower expand to fill gap Upper zone increase in density Lower margin defined by horizontal fissure Collapse due to mass obstructing main bronchus – Golden S sing

RUL Collapse

LUL collapse

Collapses forwards, in absence of a horizontal fissure on the left No clear inferior margin of collapse Lower expands to fill the space leaving a veil opacity in the left upper

zone Lingula may be involved in collapse with obstruction of the left heart

boarder. Obscures silhouette of aortic arch

LUL collapse

RML Collapse

Collapses inferiorly into oblique fissure No definable margins that relate to RML collapse Increased density adjacent to and obscuring the right heart boarder Lateral CXR demonstrate collapse clearly

RML Collapse

RML Collapse

RLL Collapse

Collapses medially causing increased density behind and adjacent to, but not obscuring, the right heart boarder Usually the lateral margin of the collapse is well defined, demarcated

by oblique fissure Evidence of right lower volume loss with depression of hila point on

the right RUL expand to occupy space

RLL Collapse

LLL Collapse

• LLL collapses medially leaving a well defined lateral margin, obscuring the medial aspect of the left hemi diaphragmatic silhouette

• Cause increased density behind the heart • Volume loss result in depression of left hilum, more vertical course of

left main bronchus, shift of mediastinum to the left and compensatory expansion of the LUL

LLL Collapse

Whole lung collapse

• An obstruction of the right or left main bronchus can cause collapse of an entire lung

• Appearance is mimics the “white out” seen in a very large pleural effusion

• The presence of mediastinal shift to the side of the opacity indicates collapse as the cause rather than an effusion that is more likely to shift the mediastinum the opposite way.

• Look at the trachea

Whole lung collapse

masses

• Opacity measuring 3cm or more in diameter • Opacity less the 3cm is called a nodule • A mass may destroy the adjacent lung as with invasive lesions, and

have ill-defined margins or displace lung as it grows and have well defined margins

masses

masses

• If the medial margin is visible but lateral margin is indistinct, the mass is probably pleural based

masses

• A mass arising from the mediastinum will have no definable medial margins but tends to have a well defined lateral margin as it displaces adjacent lung

• Masses may hide behind the diaphragm in the posterior costophrenic recess, in the apices and in the para-spinal region projected behind the heart

The Coin lesions • Discrete opacities situated within lung fields. • Not necessarily strictly circular • Mainly represent a carcinoma, other possibilities are localized areas of consolidation, and abscess

or a pleural abnormality A speculated, irregular or lobulated edge is suggestive of malignancy If calcified, likely a benign lesions. Calcification rare in malignancy Check if lesion is cavitating If airbronchograms are seen, lesion likely an area of consolidation If more than one, strongly suggests a metastatic disease Look for abnormalities peripheral to the lesion. A tumor may lead to collapse distal to it, or and

infection leading to consolidation In case of mediastinal adenopathy / bone mets, lesion likely a malignant tumor Look at previous radiographs.

Causes of coin lesions

• Benign: eg hamartoma • Malignant tumors: eg bronchial

carcinoma • Single secondary infections eg

pneumonia, abscess, tuberculosis, hydatid cyst

• Infarction • Rheumatoid nodule

Pulmonary fibrosis The CXR is an insensitive investigation for detecting pulmonary fibrosis. The advent of HRCT has demonstrated mild to moderate degrees of fibrosis that

are not detected on CXR. When fibrosis is apparent on CXR the cardinal feature is reticulation, a fine

network of lines, corresponding to fibrous thickening of the lung interstitium such that it becomes visible on CXR To make a diagnosis of fibrosis the other conditions that thicken the interstitium

such as interstitial oedema in heart failure, lymphangitis carcinomatosa and alveolar proteinosis, should be excluded or other evidence of fibrosis should be present. The presence of volume loss in the region of reticulation and/or honeycomb

destruction supports a diagnosis of fibrosis. Honeycomb destruction of the lung is primarily a feature of idiopathic pulmonary

fibrosis, is characteristically peripheral and basal in site and may be seen on CXR if severe

Image 1: CXR of a patient with idiopathic pulmonary fibrosis. The magnified area demonstrates the interlacing network of lines described as reticulation, which represent the visible pathologically thickened interstitium, in this case due to fibrosis. Image 2: CXR of an adult male with diffuse lung fibrosis. As a result there is reduced lung expansion evident on this full inspiratory film.

Pulmonary sarcoid

Sarcoidosis is a systemic granulomatous condition. The spectrum of features found in the lung enable sarcoid to mimic the

radiology of many other pulmonary pathologies. The characteristic presentation is of bilateral, symmetrical hilar

adenopathy with or without mediastinal adenopathy and the main differential for this appearance is lymphoma Lung parenchymal involvement may present with fibrosis evident as

reticulation, typically in the upper and mid zones Sarcoidosis may manifest as a nodular pattern similar in appearance to

miliary TB or consolidation, which tends to be peripheral and patchy.

Image 1: CXR of a patient with sarcoidosis. Note the bilateral hilar adenopathy (white arrows) and the likely paratracheal adenopathy Image 2: CXR of a patient with sarcoidosis presenting with multiple nodules. The appearance is difficult to distinguish from military TB radiolgically, but clinically, patients with TB are very unwell whereas those with sarcoid may have no symptoms

Chronic bronchitis

• Chronic bronchitis is a disease primarily associated with smoking and, when severe, may be evident on a CXR through the associated bronchial wall thickening, causing the bronchovascular markings to be more obvious and perceived further from the hila

chronic bronchitis

Emphysema

• Abnormal permanent enlargement of airspaces distal to terminal bronchioles, accompanied by the destruction of alveolar walls and without obvious fibrosis

• Features: Hyper translucency Low flat diaphragms Wide IC spaces Tear drop heart Bullas

emphysema

Flat diaphragm in emphysema. If <2.5cm

Pneumothorax Pneumothorax describes the presence of air in the pleural space. There are two main sources for this air, the lung or a breach of the chest

wall, e.g. trauma or surgical procedure. In the absence of a chest wall breach the cause will be lung pathology,

which at the simplest level may be a surface bleb, “bubble”, that has burst, a cause of spontaneous pneumothorax usually found in tall young men. Alternative causes include infections, particularly destructive abscesses,

malignancy or internal traumatic damage to the major airways. Air in the pleural space breaks the water seal that sticks the two layers of

pleura together allowing the lung to collapse through its inherent elasticity. A pneumothorax is evident on a CXR where there is an absence of lung

markings and a defined edge to the lung

Pneumothorax: Image 1: An adult male patient with a right-sided pneumothorax following percutaneous biopsy of an upper lobe tumor. Note

the lung edge (white arrows) beyond which there are no lung markings. Note also the junction between the right middle and lower lobes, the major fissure (diagonal black arrow).

Image 2: There is a large left pneumothorax with almost total lung collapse (white arrows) but with less collapse of the lower

part of the lung than the upper part. There is no mediastinal shift to indicate tension

Pneumothorax conts……

The size of the pneumothorax will have an impact on how long it takes to spontaneously resolve a process that may be accelerated by high dose oxygen therapy. Aspiration or drainage with an underwater seal will dramatically speed up the

resolution of the pneumothorax. If air is entering the pleural space but, due to a natural one-way valve, is unable

to escape, the volume of air will continue to rise causing an increase in volume of the pleural space pushing the mediastinum to the opposite side. The result is termed a tension pneumothorax and is a life threatening condition. On CXR, the presence of mediastinal shift away from a large pneumothorax and

flattening, even inversion, of the hemidiaphragm beneath the pneumothorax are signs of tension and urgent drainage is required

Three patients with tension pneumothorax, a major medical emergency. Note mediastinal shift from side of pneumothorax, flattening of the hemidiaphragm on affected side

Pleural effusion

• Accumulation of fluid within the pleural space • Subdivided into transudates or exudates based on protein contents • Transudates (protein <3g/dL) – often bilateral due to increased hydrostatic

pressure (eg cardiac or renal failure) or decreased colloid oncotic pressure (nephrotic syndrome or cirrhosis)

• Exudates (protein >3g/dL) – due to increase permeability of abnormal capillaries (eg infections / empyema, malignant disease, blood, collagen vascular disorders and pacreatitis)

• Lies dependently within pleural space unless loculated • Effusions in specific conditions are are often found on one particular side

only eg. Left side in pancreatitis

Pleural effusion

• Meniscus – shaped upper surface of right pleural effusion

• Loculated pleural effusion

Pleural effusion

• Lamellar pleura effusion

• Encysted pleural effusion

Trauma

Rib fractures Often always missed on CXR incase undisplaced Coz of curve of the bones, may in a part which is not well shown, in

costal cartilage which is not usually visible unless calcified A normal CXR doesn’t rule out #

Note:

The azygos vein and azygos fissure

Importance of side marker

Qn.1

Qn. 2

Qn. 3

Qn.

Ans. Cavitation: cystic changes in the area of consolidation due to the bacterial destruction of the lung tissue. Notice air fluid level

Qn. 25year old had sudden onset of left-sided chest pain. CXR shown