chest x rays

Chest Xray - Views

PA View

AP view

The clavicles project too high into the apices.The heart magnified over the mediastinum. The ribs will appear distorted or unnaturally horizontalPulmonary markings decresed visibilityBlunting of costophrenic angles

Lateral View

PositionSeen in : ant mediastinal masses, encysted pleural fluid, post basal consolidation

Other Views

• Decubitus - useful for differentiating pleural effusions from consolidation (e.g. pneumonia) ; Loculated effusions from free fluid in the pleura.

• Expiratory view and Inspiratory viewsDemonstrates Air trapping and diaphragm

movementExp : pneumothorax and interstitial shadowing

• Lordotic view Clavicles projected upPancoast Tumour

• Apical View

50 to 60 degrees

• Oblique viewRetrocardiac areaPosterior costophrenic angleChest wall

Normal Chest X-Ray

Scheme of viewing PA film1. Request form Name ,age, sex, date, clinical information

2. Technical ViewCentering, patient positionSide MarkersAdequate inspirationExposure/Penetrance

3. Soft tissue and bony cage Subcutaneous emphysema, fractures

4.Trachea Position, Outline

5. Heart and Mediastinum Shape , Size, Displacement

6.Diaphragms Outline ,Shape , Relative position

7.Pleural spaces Position of horizontal fissure, costophrenic and cardiophrenic angles

8.Lungs Local , generalized abnormalities, comparison of translucency and vascular marking sof the lungs

9.Hidden areas Apices, Posterior sulcus, Mediastinum, Hila, Bones

10. Hila Density, Position, Shape

11. Below the Diaphragm Gas shadows, Calcification

PA VIEW

• Chin up , shoulders rotated forward, taken in full inspiration

• With plate in front of chest and back to the X-ray machine

• Scapula away from the upper lung fields

• Clavicles less apically displaced

• Vertebral neural arches seen

AP VIEW

• Taken in cases when patient is too ill to stand

• Film is placed behind the back and x-ray exposure from front .

• Scapula closer to the lung fields

• Clavicles less apically displaced

• Vertebral disc spaces seen better

• Relative cardiomegaly

Technical aspects of viewing a PA film• Centering – medial ends of clavicle equidistant from

spinous process at t4/5- always look for gastric bubble,aortic arch and heart to confirm normal situs.

• Penetration – disc spaces+vertebral bodies visible down to t8/9

• Degree of Inspiration – full inspiration ant. Ends of 6th rib or post ends of the 10th rib on right hemidiaphragm. On expiration larger cardiac shadow and basal opacity due to crowding of normal vascular markings.

Trachea

• Upper part- midline• Lower part- deviates slightly around aortic

knuckle- marked on expiration• Left bronchus not clearly visualized due to

aorta• 25mm in males , 21 mm in females• Right paratracheal stripe- 60% N- 5mm• Angle of carina- 60 -75 degrees

Mediastinum and Heart

• Mediastinum, Heart, Spine , Sternum• Cardiothoracic ratio – less than 50% in PA and

less than 60% in AP. Increased in AP and expiration

• Right and Left heart borders formed • Thymus- triangular Sail shaped structure –

Wave sign of Mulvey

Diaphragm

• Right higher than left• Normal position of diaphragm, higher in

supine• Curves which steepen towards chest wall-

costophrenic angles are acue• Cardiophrenic angles may be blunted due to

presence of fat pads

The Fissures

• Horizontal fissure seen often incompletely running from the hilum to the region of the sixth rib

• Fissures seen clearly seen on lateral view• Accessory fissure- Azygos fissure comma

shaped right sided triangular based peripherally

Lungs

• Hidden areas- Apices, Mediastinum and hila, Diaphragms, Bones

• Hila- 97% left higher than right., Clearly defined borders –concave lateral borders- mainly formed by pulmonary areteries and upper lobe veins. Lymph nodes not normal

• Bronchovascular markings seen upto – 2/3rd of the lung field

• Lymphatics – normally not seen

Lung zones• When describing the lungs divide them into three zones -

upper, middle and lower.

• Each of these zones occupies approximately one third of the height of the lungs.

• The lung zones do not equate to the lung lobes.

• Upper zone- from 2nd costal cartilage to axilla• Middle zone- between 2nd and 4th costal cartilage.• Lower zone- below 4th costal cartilage.

Lymph Nodes

• Bronchopulmonary( hilar) nodes – appear as hilar masses

• Carinal nodes- widening of the carinal angle• Tracheobronchial nodes- right paramedian

stripe• Anterior, Posterior, Paratracheal, parietal

Below the diaphragm

• Gas • Chilaiditis syndrome

Soft tissue and Bony Cage

• Breasts may partially obscure the lungs.• Skin folds tend to be confused with consolidation

as they overlap the lung fields

• Sternum• Clavicle• Scapulae• Ribs- rib notching• Spine- check bone and rib destruction

ABCDEFGHI!!

• Bones and Soft tissue• Airway• Cardiac Silhouette, Mediastinum.• Diaphragms• Effusion• Fields of lung• Gastric Air Bubble• Hilum• Instruments.

Line shadows

By: Michelle Rasiah

Introduction

• Normal blood vessels and fissures form linear shadows

• Certain lung diseases also form linear shadows • Linear shadow < 5 mm wide • Band shadow > 5 mm thick

Causes for linear shadows

• Kerley’s lines • Plate-like atelectasis • Pulmonary infarcts • Thickened fissures • Pulmonary / pleural scars • Bronchial wall thickening • Sentinel lines • Curvilinear shadows • Anamolous vessels • Artefacts • Bronchoceles

Kerley lines

• Pulmonary lymphatics are usually not visible• Lymphatics drain the interstitial fluid and foreign particles • They run in the interlobular septa and drain to the hilum• Thickened lymphatics and surrounding connective tissue =

Kerley lines • Divided into 3 types

– Kerley A lines – thickened deep septa – Kerley B lines – thickened interlobular septa – Kerley C lines

Acinus 5 - 6 mm in diameter alveoli, alveolar duct, resp. bronchiole

3 - 5 acini = secondary pulmonary lobule

Each lobule is separated by septa (interlobular

septa)

Thickening of these septa = Kerley B lines

Formation of Kerley B lines

Types Kerley A line Kerley B line Kerley C line

Thin Thin, transverse, faint Fine

Non branching Non branching Interlacing lines

2 – 6 cm long 1 -3 cm long Seen throughout lung

1 – 2 mm thick 1- 2 mm thick “Spider web” like appearance

Radiating from hila Lateral part of lung base extending to pleura (common in costophrenic angle)

not following course of artery, vein or bronchi

Frequently seen than A &C lines

Lines arranged in step ladder like pattern (0.5 to 1 cm apart)

ALWAYS perpendicular to pleural surface

• Kerley B lines can be:

• They are present in the base of the lung due to hydrostatic pressure and gravity

Transient Persistent

Pulmonary edema Dilated lymphatics Chronic interstitial edema Hemosiderin dust deposition Interstitial fibrosis

Impaired diaphragmatic motion

Underventilation

Collapse of small pulmonary sub divisions

Disk atelectasis

Fleischner line formation

Differentiation Fleischner’s lines Kerley B lines Linear scars

Fewer in number (1 -2) More in number May show fine strands emanating from borders

Irregularly placed Regularly placed (0.5 to 1 cm gaps)

Associated pleural effusion

Located deep in lung Superficial Permanent

Thicker Thin

Thickening of fissures

Mucous filled bronchi

NODULAR LESIONS

VINYAS NISARGA(080201014)

• Nodular lesions could be classified as 1. solitary pulmonary nodules 2. Multiple pulmonary nodules• Solitary nodule is defined as an x-ray density completely surrounded by

normal aerated lung with circumscribed margins of any shape usually 1-6cm in greatest diameter.

• If its <3cm → ‘Coin lessions’• If > 3cm → massesCannon ball lesions:Multiple nodules, widely disseminated,usually multiple,

clearly demarcated 1- 2cm in diameter circular shadows throughout the lung fields (characteristic of secondary deposits)

Milliary shadows : Multiple small shadows 2-4mm in diameter

Solitary pulmonary nodule causesMalignant• Primary nodule• Secondary nodule• Lymphoma• Plasmacytoma• Alveolar cell carcinoma Benign• Hamartoma • Adenoma• Connective tissue tumoursGranuloma• Tuberculosis• Histoplasmosis• Paraffinoma• Sarcoidosis

Infection • Round pneumonia • Abscess • Hydatid• Amoebic • Fungi• ParasitesOthers• Pulmonary haematoma, Pulmonary infarct• Collagen diseases-Rheumatoid arthritis, Wegener's granulomatosis• Congenital-Bronchogenic cyst, Sequestrated segmen,Congenital bronchial

atresia , AVM• impacted mucus • Amyloidosis, Intrapulmonary lymph node• Pleural- fibroma, tumor, loculated fluid

Multiple nodulesTumours• Benign-hamartoma, laryngeal papillomatosis• Malignant-metastases, lymphomaInfection• Granuloma-tuberculosis, histoplasmosis, fungi i• Round pneumonia• Abscesses• Hydatid cystsInflammatory• Caplan's syndrome• Wegener's granulomatosis• Sarcoidosis• Drugs

Vascular• Arteriovenous malformations• Haematomas• InfarctsMiscellaneous• Mucus impaction• Amyloidosis

Multiple nodules –canonball appaernace (choriocarcnoma)Metastatic lesions

Miliary TB

Tuberculoma: It appears Round or oval, sharply circumscribed nodule that is seldom more than 4 cm in diameter. Central calcification and satellite lesions are common, as is calcification of hilar lymph nodes.

This X-ray shows :Single smooth, well-defined pulmonary nodule in the left upper lobe. In the absence of a central nidus of calcification, this appearance is indistinguishable from that of a malignancy.

TUBERCULOMA:(A) Frontal and (B) lateral views of the chest show a large left lung soft-tissue mass (arrows) containing dense central calcification

Rheumatoid nodules

Large nodules in pulmonary parenchyma bilaterally present, discrete similar to opacities of metastatic lesions – Rhuematoid arthritis

Bronchogenic Carcinoma

Carcinoma of bronchus. A large, round soft-tissue mass ispresent at the right apex. Blunting of the right costophrenic angle is due toa small pleural effusion.

Hamartoma-popcorn calcification

Histoplasmosis-calcified granuloma(coin lesion)

Pulmonary infarction

Chest radiograph with ‘classical’ appearance of a pulmonary infarction – a wedge-shaped lesion peripherally set against the pleura

Chest X ray after 4 days, prior to treatment, showing massive increase in volume of lesion.

Lung abscess (air fluid level)

Alveolar Shadows

Neena S

Air-space (Acinar/alveolar) pattern

• When distal airways and alveoli are filled with fluid, whether it is a transudate, exudate or blood, acinus forms a nodular 4-8mm shadow.

• These coalesce into fluffy ill-defined round or irregular cotton-wool shadows.

• Non-segmental, homogenous or patchy, but frequently well defined adjacent to fissures.

Cont…

• Vascular markings usually obscured locally.• Air bronchogram and silhouette sign are

characteristic • Ground-glass appearance of generalised

homogenous haze with a “bat’s wing” or “butterfly” perihilar distribution may be seen, sparing the peripheral lungs.

Silhouette Sign

• An intrathoracic lesion touching a border of the heart, aorta, or diaphragm will obliterate that border on the radiograph.

• An intrathoracic lesion not anatomically continous with a border of one of these structures will not obliterate that border.

• Eg. Lower lobe pneumonia, disease of lingula

Causes of air space filling• Pulmonary edema

– Cardiac– Non-cardiac

• Hypoalbuminemia• Uraemia• ARDS• Mendelson’s syndrome• Heroin overdose

• Infections– Localised– Generalised eg.

Pneumocystis, parasites, fungi

• Neonatal– Aspiration– Hyaline membrane disease

• Alveolar blood– Pulmonary haemorrhage– Goodpasture’s syndrome– Pulmonary infarction

• Tumours– Alveolar cell carcinoma– Lymphoma, leukaemia– Metastatic adenocarcinoma

• Miscellaneous– Alveolar proteinosis– Eosinophilic lung– Sarcoidosis– Amyloidosis– Wegener’s granulomatosis– Allergic bronchopulmonary

aspergillosis

Pulmonary Edema

• Produces air space opacities with variable distribution.

• Sparing of the apices and extreme lung bases.• “Butterfly” or “Bat wings” distribution – central

lungs affected more.• With progression – opacities coalesce to form a

“white-out” on chest radiograph.• Blurring of blood vessels occurs.• Air bronchogram – indicating intra alveolar

edema.

picture

Radiologic signs of collapse

Preethi .N.B

The term collapse is used when a whole lobe or lung is involved. Atelectesis is defined as diminished volume affecting all or part of a lung, whichmay or may not include loss of normal lucency in the affected part of lung . Pulmonary atelectasis can be divided into six types, based on mechanism: resorptive, adhesive, compressive, passive, cicatrization, and gravity-dependent

LOBAR ATELECTASISRadiologic signs of lobar atelectasis :- Direct or Indirect . Direct signs include increased opacification of the airless lobe and displacement of fissures.

Indirect signs include displacement of hilar and cardiomediastinal structures toward the side of collapse, narrowing of the ipsilateral intercostal spaces, elevation of the ipsilateral hemidiaphragm, compensatory hyperinflation and hyperlucency of the remaining aerated lung, and obscuration or desilhouetting of the structures adjacent to the collapsed lung (eg, diaphragm and heart borders). Additional radiologic features vary according to the site of atelectasis.

RADIOLOGY OF PLEURAL DISEASES

Nikitha James 080201018

PLEURAL EFFUSION

• Pleural effusion initially manifests as basal peripheral opacities that first fill the costo-phrenic angle.

Curve Of Ellis

Massive Pleural Effusion

Pneumothorax

• Chest X-ray PA view shows– Sharply defined edge of the deflated lung– Complete translucency between the lung and the

chestwall.

Tension Pneumothorax

RADILOGICAL FEATURES OF CONSILIDATION

Consolidation Consolidation- replacement of air in one or more acini by fluid

or solid material, but does not imply a particular pathology or etiology.

Communications between the terminal airways allows fluid to spread between adjacent acini- responsible for larger area of involvement

Commonest causes Acute inflammatory exudate from pneumonia. Non cardiogenic pulmonary oedema Cardiogenic pulmonary oedema Hemorrhage Aspiration

Radiologic features

AIR BRONCHOGRAM-contrast between the column of air which is present

in the airway and the surrounding opaque aciniNormally the lung fields are radioluscent and the

bronchi are not separately visualisedBut when, there is opacification of the alveoli due

to various reasons (eg: fluid accumulation is pulmonary oedema)the bronchi stand out as radiolucent in contrast to the adjacent alveoli that are radio opaque

an x-ray for a patient with right middle zone consolidation and demonstrates air bronchograms

Silhouette sign: If the airspace adjacent to one of the normal mediastinal or diaphragmatic contours is filled with dense material i.e. consolidated, then the normal air-soft tissue interface is lost and the normally seen edge of the silhouette disappears

.

Upper lobe consolidation

Middle and Lower lobe consolidation

Left lower lobe consolidation

Chest X Ray in Mediastinal Lesions

Manasa

• On the lateral radiograph

• drawing an imaginary line anterior to the trachea and posteriorly to the inferior vena cava.

• The middle and posterior compartments can be separated by an imaginary line passing 1 cm posteriorly to the anterior border of the vertebral bodies.

• Approximately 60% of all mediastinal masses arise in the anterior mediastinum, 25% appear in the posterior mediastinum, and 15% occur in the middle mediastinum

• Most masses (> 60%) are:– Thymomas– Neurogenic Tumors– Benign Cysts– Lymphadenopathy

• In children the most common (> 80%) are:– Neurogenic tumors– Germ cell tumors– Foregut cysts

• In adults the most common are:– Lymphomas– Lymphadenopathy– Thymomas– Thyroid masses

Superior mediastinum• origins of the Sternohyoid and Sternothyroid• the aortic arch• the innominate artery• the thoracic portions of the left common carotid and

the left subclavian arteries• the innominate veins• the upper half of the superior vena cava• the left highest intercostal vein• the vagus, cardiac, phrenic, and left recurrent nerves;

the trachea, esophagus, and thoracic duct; • the remains of the thymus, and • some lymph glands

• A lung mass abutts the mediastinal surface and creates acute angles with the lung, while a mediastinal mass will sit under the surface creating obtuse angles with the lung

LUNG MASS OR MEDIASTINAL MASS ?

Anterior Mediastinum

• loose areolar tissue, • some lymphatic vessels which ascend from

the convex surface of the liver, • two or three anterior mediastinal lymph

glands• small mediastinal branches of the internal

mammary artery.

Anterior Mediastinum

SignsObliterated retrosternal clear spaceObliterated cardiophrenic angleHilum overlay sign

• Hilum Overlay Sign• When there is a mediastinal mass and you still

can see the hilar vessels through this mass, then you know the mass does not arise from the hilum. This is known as the hilum overlay sign.Because of the geometry of the mediastinum most of these masses will be located in the anterior mediastinum.

• The four T's make up the mnemonic for anterior mediastinal masses:

• Thymoma (myasthenia, upper anterior mediatinum)

• Teratoma (germ cell)• Thyroid• Terrible Lymphoma

• thymoma

THYMOMA

LYMPHOMA

.

Middle MediastinumIt contains• The heart enclosed in the

pericardium• the ascending aorta• the lower half of the

superior vena cava with the azygos vein opening into it

• the pulmonary artery dividing into its two branches

• the right and left pulmonary veins

• the bifurcation of the trachea and the two bronchi

• the phrenic nerves• some bronchial lymph

glands.

Middle Mediastinum

SignsWidened paratracheal stripesAP window massDisplaced azygoesophageal recess on the rightLateral ‘doughnut’

• Adenopathy Infection (fungal and mycobacterial) Neoplasm (bronchogenic carcinoma, metastases, lymphoma, leukemia)Sarcoidosis

• Aneurysm/vascular• Abnormalities of development

Bronchogenic cyst Pericardial cyst Esophageal duplication cyst

• Saccular aortic aneurysm

BRONCHOGENIC CYST

Posterior Mediastinum

• Thoracic part of the descending aorta• the azygos and the two hemiazygos veins• the vagus and splanchnic nerves,• the esophagus• the thoracic duct• some lymph glands.

Common • Neural tumors • Neurogenic (neuroblastoma,

ganglioneuroma, ganglioneuroblastoma)

• Nerve root tumors (schwannoma, neurofibroma, malignant schwannoma)

Less common • Paraganglionic cell tumors

(chemodectoma, pheochromocytoma)

• Spinal tumor (metastases, primary bone tumor)

• Lymphoma • Invasive thymoma

• Mesenchymal tumor (fibroma, lipoma, leiomyoma, hemangioma, lymphangioma)

• Abscess • Pancreatic pseudocyst • Esophageal varices • Hematoma • Traumatic • pseudomeningocele • Bochdalek hernia • Extramedullary

hematopoiesis • Descending thoracic aortic

aneurysm

On conventional radiographs look for:• Cervicothoracic Sign• Widening of the paravertebral stripes

• Cervicothoracic sign• The anterior mediastinum stops at the level of the

superior clavicle.Therefore, when a mass extends above the superior clavicle, it is located either in the neck or in the posterior mediastinum.When lung tissue comes between the mass and the neck, the mass is probably in the posterior mediastinum. This is known as the Cervicothoracic Sign.

SCHWANNOMA