Chest X-rays
Anatomy
The Chest X-ray (typically the most common) primarily showcases the thoracic cavity, which includes the lungs, heart, diaphragm, rib cage and mediastinum. The mediastinum is the area between the lungs that contains the heart, oesophagus, trachea, thymus, lymph nodes, nerves, fat, and large blood vessels.
The key anatomical structures in a chest x-ray include the lung fields (the areas at the top of the lungs), the location of the hila (connection of essential vessels to lungs), costophrenic angles 9harp angle where the diaphragm and ribcage meet), trachea and clavicles.
By understanding these anatomical structures, we can identify abnormalities and pathologies.
Most common pathologies:
- Pleural Effusion
- Pneumonia
- Cardiomegaly
- COPD – Emphysema
- Lung Cancer
Positioning
In a chest x-ray, there are 2 main positions – PA (posteroanterior) and a lateral projection.
For a PA view, the patient stands with their chest against the image receptor/board, shoulders rolled forward to move the scapulae out of the lung fields, and chin raised**. The central ray is directed perpendicular to the mid-thoracic level at T7.
**In real workplace setting, most patients cannot place their chins onto the chin rest as it is made for a really tall person, so do not worry about this.
In a lateral/sideways view, it requires the patient to stand with their side against the receptor, arms raised above their head. It is important to raise their arms above their head as it minimises any distortion.
Take a watch this video for a futher explanation:
Image References:
Mediastinum Diagram – Cleveland Clinic
Ribcage – Encyclopaedia Brittania
Chest X-ray – EBM Consult
PA view – Radtechonduty.com
Lateral view – Clover Learning