practical thoracicradiology

Thoracic radiology

Dr.Khaleel Ibraheem
MBChB,DMRD,CABMS-rad

Approach to chest x ray

Chest consolidation

Diffuse lung lesions

Differentiating the Causes of an Opacified Hemithorax

Atelectasis of an entire lung
A large pleural effusion
Pneumonia of an entire lung
And a fourth cause: Post-pneumonectomy – removal of an entire lung

Atelectasis of the Lung

There is a shift of heart and hemidiaphragm toward side of opacification (toward side of volume loss)

Pleural Effusion

It acts like a mass
Pushing the heart and trachea away from the side of opacification

pneumonia

The hemithorax is opaque and there isno shift of the heart or trachea
There may be an air bronchogram sign present

postpnemonectomy

The hemithorax eventually fibroses and becomes opaque
Clues: There is frequently a resected fifth rib and/or surgical clips

quiz

Pleural effusion

Subpulmonary
On the frontal film, the highest point of the apparent right hemi diaphragm is displaced laterally (it is usually in the center).

Blunting of CP angle

Normally there are 2-10cc of fluid in the pleural space
When >75cc accumulate, the posterior costophrenic (CP) sulci, seen on the lateral film, become blunted
When 200-300cc accumulate, the CP sulci on the frontal film become blunted

Meniscus sign

Pleural fluid tends to rise higher along its edge producing a meniscus shape medially and laterally
Usually only lateral meniscus can be seen
The meniscus is a good indicator of the presence of a pleural effusion

Loculated effusion

Occurs secondary to adhesions which form between visceral and parietal pleura
Adhesions more common with blood(hemothorax) and pus (empyema)
Loculated effusions have unusual shapes or positions in thorax

hydropneumothorax

If both a pneumothorax and a pleural effusion occur together, it is called a hydropneumothorax
A hydropneumothorax is usually due to trauma, surgery, bronchopleural fistula
It is characterized by an air-fluid level in the hemithorax



A straight edge,indicative of a fluid interface, in this case an air-fluid interface, is seen on the right.

pneumothorax

When air enters the pleural space, the parietal and visceral pleura separate making the visceral pleura visible
The thin white line of the visceral pleura is called the visceral pleural white line
You must see the visceral pleural white line to make diagnosis of pneumothorax!


Simple pneumothorax




In a simple pneumothorax, there is no shift of the heart or mediastinal structures (trachea)
Air in left hemithorax balances the air in the right hemithorax

Tension pneumothorax

Progressive loss of air into pleural space causing a shift of the heart and mediastinal structures away from side of pneumothorax
Opposite lung is compressed
Respiratory function severely compromised