NORMAL CHEST X RAY AND

COLLAPSEDr .Aabid Al Rahiman

REVIEW

• Normal chest x ray

• Collapse of lung• Types and radiologic appearances

A routine pattern of plain x-ray film reporting can be ensured for proper scrutiny.The 14 step is listed below

1. Name2. Date3. IP/OP No4. Markers(R/L)5. Orientation6. Penetration7. Inspiration8. Rotation9. Angulation

Pre read

Quality

10.Soft tissue/bony structures11.Meadiastinum12.Diaphragms13.Lung fields14.Abdominal structures

Findings

Technical adequacy

Factors to be considered include

• Orientation• Inspiration• Penetration• Rotation• Angulation

ORIENTATION• Position of patient and the x ray beam

• PA radiograph is obtained with x ray traversing the patient from posterior to anterior and striking the film

• AP radiograph is obtained with the x ray traversing the patient from anterior to posterior striking the film.

• The cardiac border will appear larger on an AP x ray due to magnification effect of more anteriorly located heart relative to the film

PA vs APIn PA view• Clavicles don’t project too high into apices or thrown above the apices

(more horizontal)

• Heart magnification reduced, preventing appearance of cardiomegaly

• Scapula are away from lung fields

• Ribs are obliquely oriented in PA view

• Spine and posterior ends of ribs are clearly seen

Why PA is preferred over AP?• Reduces magnification of heart-preventing appearance of cardiomegaly.• Reduces radiation dose to radiation sensitive organs such as thyroid, eye,

breast.• Visualised maximum areas of lung• Moves scapula away from lung field• More stable positioning for the patient as they can hold on to the unit-

reduces patient movement• Compression of breast tissue against the film cassette reduces the

density of tissue around CP bases therefore visualizing them more clearly.

Inspiration• The volume of air in the hemi thorax will affect the configuration of heart

in relation to cardiac size

• The vascular patterns in lung fields will be accentuated with a shallow inspiration

• The level of inspiration can be done by counting ribs

• Visualization of 10 posterior ribs or six anterior ribs on an upright PA radiograph projecting above the diaphragm would indicate a satisfactory inspiration

Penetration• Refers to adequate photons traversing the patient to expose the

radiograph

• The lack of penetration renders the area whiter than with an adequate film and can simulate effusion or pneumonia

• In an ideal x ray the thoracic spine should be barely visible

• In lateral view 2 sets of ribs should be seen ,sternum seen, spine appears clearer as it goes down

Rotation• Ideally clavicle should be equidistant from the spinous process• Rotation of the radiograph is assessed by judging the position of

clavicle heads and thoracic spine process• Rotation of patient distorts mediastinal anatomy and makes

assessment of cardiac chambers and their hilar structures difficult• Chest wall tissue also contributes to increased density over the lower

lobe fields simulating disease

Angulation• With patient in a more lordotic projection and in apicogram the

clavicles will project superiorly relative to the upper thorax again causing some distortion of the normal mediastinal anatomy.

• With the lordotic projection of the ribs assume a more horizontal orientation

• Occasionally a lordotic x ray can be obtained intentionally to better visualize structures in thoracic apex obscured by overlying bony structures

VIEWS OF X RAY

Significance of different views• AP viewIt is useful in differentiating free and loculated fluid

• Lateral view• The only view that provides information of localization of different

lobes and segments• Observation on lateral view include –clear spaces, vertebral

translucency and outline of diaphragms

• Oblique viewoIt is helpful in localizing a lesion, in visualizing its borders and in

projecting it free of overlying structuresoOblique view is preferred to lateral view in case of bilateral disease

• Decubitus viewIts helpful in demonstrating small pneumothorax or pleural effusions.

• Lordotic view This view helps in confirming middle lobe and lingular abnormalities• This view is also helpful in determining the anteroposterior location of

a lesionApicogram view when there is doubt in apical area

SOFT TISSUES• Soft tissues cast shadow on plain radiographs which have less dense

radio opacity• Breast shadow result in increased opacity over lower thorax bilaterally• Nipple shadow may appear as round opacities in the 4th or lower

anterior intercostal space• Breast and nipple shadow are usually bilateral and symmetrical• Linear shadow may result from loose skin fold• A faint soft tissue shadow parallel to the clavicle results from over

lining skin fold and subcutaneous tissue(clavicular companion shadow)

BONY THORAX• Outlines the shoulder girdle, ribs, cervical and thoracic vertebrae

• Sternum is often well outlined

• Shape of thorax varies with age and body habitus

• Angulations of ribs varies with body types. downward angulations :minimal in short hypersthenic individual and maximal in asthenic patient.

• Intercostal spaces are numbered according to the intercostal rib above them. The ribs and interspaces are designated into 2 groups: anterior and posterior

• The costal cartilages are not visible except when calcified which then assume characteristic mottled appearance(periphery in males and central in females)

• Diaphragm in a normal adult is slightly higher on right compared to the left.

MEDIASTINUM• Space between the right and left pleura in and near the median sagittal

plane of the chest• It is bounded by posterior surface of sternum and anterior surface

thoracic vertebrae• It contains all the thoracic viscera except for the lungs• It is divided into superior and inferior parts by an imaginary horizontal

line passing through the sternal angle of Louis backwards to the lower border of T4 vertebrae• The inferior mediastinum is further divided into the anterior, middle

and posterior mediastinum by fibrous pericardium.

DIVISION OF MEDIASTINUM1. FELSON’S CLASSIFICATION

2. SUTTONS CLASSIFICATION

FELSONS CLASSIFICATION• The mediastinum is divided into anterior, middle and posterior

compartments

• An imaginary line is traced upward from the diaphragm along back of the heart and front of the trachea to the neck. This divides the anterior from middle mediastinum

• A secondary imaginary line connects a point on each of the thoracic vertebrae 1 cm behind its anterior margin. This divides the middle from posterior mediastinum.

SUTTONS CLASSIFICATION• Mediastinum is divided into three parts1. Anterior2. Middle3. Posterior• Anterior division lies in front of the anterior pericardium

• Middle division within the pericardial cavity

• Posterior divison lies beyond the post pericardium and trachea

Mediastinal structures• The hila is made up of the main pulmonary arteries and major bronchi

• The left hilum is higher than right

• Lymph nodes are not normally seen on a chest x ray.

The main pulmonary artery on the right side passes anterior to the right main bronchus, whereas the main pulmonary artery on left side passes posteriorly and hooks over the main bronchus.

• On lateral projection the left pulmonary artery is posterior to a line drawn down the tracheal air column.

• The trachea appears an air shadow coursing down (c6) the midline of chest and terminating at the carina

• The left and right main stem bronchi, as well as the lobar bronchi may be evident

• A very subtle deviation to the right at the level of aortic arch, moderate deviation to the right is common in infants.

• Thymus is usually visible in infants and occupies the superior part of anterior mediastinum(causes widening of mediastinum when present).lateral view to confirm it.

• When there is enough air in the oesophagus a trachea oesophageal stripe may be seen.

HEART• Size

• Shape

• Diameter(>1/2 thoracic diameter is enlarged heart)

• AP views make heart appear larger than it actually is.

• The dotted line extends from carina to the anterior costophrenic angle.

Cardiothoracic ratio (CTR) = Cardiac Width : Thoracic Width

Aortopulmonary window• A space located underneath the aortic arch and above the left

pulmonary artery

• Contains fat

• On a PA projection ,it appears as a concave shadow. If adenopathy is present, it manifests as a convex shadow.

DIAPHRAGM• The left and right diaphragm appear as sharply marginated domes.

• The peripheral margins of the diaphragm define the costophrenic sulci

• The right diaphragm is higher than left and will appear larger on lateral chest film

• A difference greater than 3 cm in the level of two hemi diaphragm is significant.

Cardiophrenic angle & costophrenic angle

Posterior costophrenic recess/sulci

Lung zones

PULMONARY FISSURES• Formed with visceral pulmonary pleura

Right lung •Major fissure-oblique fissure•Minor fissure-horizontal fissure

Left lung •Major fissure-oblique fissure

• Oblique fissure more clearly seen on lateral view from T4-T5 vertebrae to reach the diaphragm.

• Right oblique fissure lies at most inferior 4-5 cm behind the sternum and left oblique is positioned more posterior.

• Horizontal fissures are more clearly seen on PA view extending from right hilum to sixth rib in axillary line

Fissures divide lungs into lobes• Right lungUpperMiddle Lower

• Left lung Upper Lower

Interfaces and stripes• There are six mediastinal stripes.1. Paravertebral stripe2. Right paratracheal stripe3. Azygoesophageal stripe4. Anterior junction line5. Posterior junction line6. Aortopulmonary stripe

Paravertebral stripe• Left paravertebral stripe is almost always visualised on well

penetrated frontal cxr.

• This is because the descending aorta displaces the adjacent lung laterally. This displacement causes pleural surface and lung edge to be seen tangentially as they pass lateral to paravertebral soft tissues from front to back.

• Right paravetrbral stripe is not visualised until middle age, when age related osteophytes are present and displaces the adjacent pleura laterally.

Right paratracheal stripe• Formed where right lung abuts the right side of trachea.

• Left side of trachea does not abut with left lung-so no stripe on left side.

Azygo oesophageal line• Right lung abuts right side of oesophagus and azygous vein.

• Extends below aortic arch to diaphragm

Anterior junction line• Formed where two lungs abut each other anteriorly below the

manubrium

• Line made up of four layers of pleura(parietal and visceral layer pleura surrounding both lungs)

Posterior junction line• Formed where the lungs abut each other posteriorly

• It extends above clavicle to the level of arch of aorta

• Also formed of four layers of pleura

Aorto pulmonary stripe• In some people a segment of mediastinal pleura does not blend with

outline of mediastinum ,but is reflected as a straight line between main pulmonary artery and aortic arch.

COLLAPSE

TYPES OF COLLAPSE OR ATELECTASIS• OBSTRUCTIVE

• COMPRESSIVE

• CICATRISATION (FIBROTIC)

• ADHESIVE COLLAPSE

OBSTRUCTIVE (RESORPTIVE)• Intrinsic occlusion1. Tumour2. Mucus plug3. Foreign body

Compressive(passive, relaxation)• Pleural fluid

• Pneumothorax

• Adjacent intrapulmonary space occupying lesion

Fibrotic contraction• Tuberculosis

• Radiotherapy

• Pulmonary fibrosis

Adhesive collapse• Neonatal surfactant deficiency

• Adult respiratory distress syndrome

• Complication of smoke inhalation

Lobar collapse • Cardinal features –increased opacity of collapsed lobe and volume loss.• DIRECT SIGNS OF VOLUME LOSS1. Displacement of fissures –most reliable sign

2. Pulmonary vessels and bronchi becomes more crowded on collapsed lung.

3. Hilar elevation in upper lobe collapse

4. Hilar depression or small hila-in lower lobe collapse

• Indirect signs

1. Compensatory hyperinflation of other lobes

2. Mediastinal shift

3. Elevation of hemi diaphragms-not reliable sign

4. Shifting granuloma sign- Hyper expansion results in change in position of lung lesions like granuloma

JUXAPHRENIC PEAK SIGN• Ancillary sign in upper lobe

collapse.

Collapse of the right lower lobe• Oblique fissure moves posteriorly and medially. The medial displacement of

this fissure causes it to be seen in profile and it forms the lateral edge of triangular density projected over heart.

• Right hilum is depressed

• Right lower lobe pulmonary artery not visualized

• Medial aspect of right dome of diaphragm is obscured

• Lateral margin of adjacent vertebrae is effaced.

• Right lower lobe collapse with triangular opacity not obscuring the diaphragm

• Increased density over of posterior costophrenic angle and loss of silhouette of right diaphragm posteriorly

Superior triangle sign• Triangular density to the right of

mediastinum due to displacement of anterior junctional structures

Left lower lobe• Oblique fissure moves posteriorly and medially. The medial displacement and rotation

of the fissure causes it to be seen in profile and it forms lateral edge of triangular density superimposed over heart.

• Left hilum lies lower than usual

• Left lobe pulmonary artery not visualized

• Medial aspect of left dome of diaphragm obscured

• Lateral margin of adjacent vertebrae effaced

Spinnaker Sail sign

Flat waist sign• Seen in extensive left lower lobe collapse

• Flattening of aortic knuckle and main pulmonary artery-due to cardiac rotation and displacement to left

• Loss of superior aortic knuckle

Collapse of middle lobe• Horizontal fissure moves inferiorly

• Blurring of right heart border

• Position of hilum doesn’t alter

• Density in collapsed lobe may be obvious or very subtle

Right upper lobe• Horizontal fissure moves superiorly

• Right hilum is elevated

• Collapsed lung is white

• In adults look for GOLDEN S Sign-when a tumour at the right hilum is the cause of the collapse.

• This reversed S is made up of an elevated horizontal fissure and a bulky tumour at the hilum.

Collapse of left upper lobe• Veil like density covers much of left hemi thorax. This is due to lack of

aeration within collapsed upper lobe

• Left heart border is obscured-in whole or part

• Left hilum is elevated

• LUFTSICHEL SIGN- cresentic lucency around the left side of aortic knuckle. It is caused by the over expanded apical segment of left lower lobe positioning between the collapsed lobe and the aortic arch.

Lingular collapse

Whole lobe collapse

Combination of collapse

THANK YOU