chest X-ray

Criteria for the optimal CXR:

Positioning, Rotation & tube Film Distance

Rotation

Inspiration

The patient should be examined in full inspiration , The diaphragm should abe found at the level of the 8th to 10 10th posterior rib or 5th to 6th anterior rib on good inspiration
Inspiration

Adequate penetration

Good Penetraion
For good penetration the thoracic discs spaces should be barely visible through the heart but bony details of spine are not usually seen, on the other hand penetration is sufficient that bronchovascular structures can usually seen through the heart.

underpenetrated

Over penetrated

Some useful Radiological Signs

On the lateral CXR the spine appears to be darken as you move caudally.
Silhouette sign: Loss of lung/soft tissue interface caused by a mass or fluid in the normally air filled lung, the sign is commonly applied to the heart, aorta, chest wall & diaphragm, can help to determine the location anatomically

Lungs Airways Pulmonary Vesseles. Heart. Mediastinum. Bones. Soft tissues.

Lung Anatomy


The left lung has two lobes and the right has three Each lobe has its own pleural covering The horizontal fissure (right) is often seen on a normal frontal view The oblique fissures are often seen on a normal lateral view . Lobes and fissures This cut-out of a lateral chest x-ray shows the positions of the lobes of the right lung On the left the oblique fissure is in a similar position but there is usually no horizontal fissure, and so there are only two lobes on the left.

consisting of: The major bronchi The pulmonary veins and arteries. Lymph nodes on eachside(not visible unless abnormal). Key points: The hila are not symmetrical but contain the same basic structures on each side. The left hilum is often higher than the right Both hila should be of similar size and density. If either hilum is bigger and more dense, this is a good indication that there is an abnormality.


Soft tissues The soft tissues are often overlooked when viewing a chest x-ray, however, abnormalities of the soft tissue may give important clues to a diagnosis. Whenever you look at a chest x-ray, have a look at the soft tissues, especially around the neck, the thoracic wall, and the breasts. Soft tissue fat This close-up demonstrates a normal fat plane between layers of muscleFat is less dense . than muscle and so appears blacker. Note that the edge of fat is smooth. Irregular areas of black within the soft tissues may represent air tracking in the subcutaneous layers. This is known as surgical emphesyma.

Lung lesions

a. TB b. abscess c. ruptured hydatid cyst

is a radiological sign that refers to non-specific air-space opacification on a chest radiograph or chest CT.

Lobar consolidation Where increased density/opacity is seen in individual lung lobes. Sharp delineation can be seen when consolidation reaches a fissure, since it does not cross. Air bronchograms can also be seen due to bronchi becoming visible against the dense diseased tissue. Volume loss is usually not seen.. Multi-focal consolidation Multiple areas of opacity seen throughout the lung most often is due to bronchopneumonia, starting from bronchi and spreading outwards. Usually ill defined with peripheral distribution. Neoplasms such as a primary malignancy or metastasis can also cause this picture.

Right upper lobe consolidation Radiological sign in chest radiograph Dense opacity seen above the horizontal fissure. Air-bronchogram line The lower border of the consolidation is sharply delinated by the horizontal fissure suggesting it lies in the anterior segment of the RUL Some loss of outline of the upper right heart border may be apparent

The Golden S-sign

Lateral chest XR film the opacity is tongue like shape, versus (triangular in shape) in RT middle lobe consolidation seen in lateral chest XR film

Non-specific signs indicating left sided atelectasis are usually also be present including:


circumscribed collection of pus within the lung, is are potentially life threatening. They are often complicated to manage and difficult to treat


Plain radiograph Shape : abscess is usually round in all projections an abscess may form an acute angle with the costal surface / chest wall empyema is usually lentiform
Lung Abscess
Empyema


By CT Scan: 1.relationship to adjacent bronchi / vessels abscesses will abruptly interrupt bronchovascular structures empyema will usually distort and compress adjacent lung 2.split pleura sign thickening and separation of visceral and parietal pleura is a sign of empyema 3.abscesses have thick irregular walls empyema are usually smoother 4.angle with pleura abscesses usually have an acute angle (claw sign), empyema have obtuse angles

Empyema

This case demonstrates typical features of a white-out hemithorax due to a large pleural effusion in a supine patient.

1. squamous cell carcinoma of the lung

2. adenocarcinoma of the lung
3. large cell carcinoma of the lung
4. small cell carcinoma of the lung

Tumor Types:

The appearance depends on the location of the lesion as follows:

Plain Film:

Plain films demonstrate a soft tissue opacity at the apex of the lung. Occasionally with rib involvement with extension into the supraclavicular fossa may be evident with surrounded bony destruction . Lordotic views may be helpful . Most important complication is involvement of the sympathetic chain >>>> * Ptosis * Meiosis * unhydrosis