From the Guidelines
When interpreting a chest radiograph, a systematic approach should be used, following a structured review pattern to ensure no important findings are missed, as this is crucial for identifying potential life-threatening conditions. This approach involves checking patient information and examining the technical quality of the image, ensuring proper penetration, rotation, and inspiration. Then, a structured review pattern should be followed:
- Examine the lungs for abnormal opacities, nodules, or infiltrates;
- Assess the heart size and contour;
- Evaluate the mediastinum including the trachea and major vessels;
- Inspect the pleura for effusions or pneumothorax;
- Examine the diaphragm and costophrenic angles;
- Check the bones and soft tissues for fractures or abnormalities. The "ABCDE" approach can be helpful: Airway (trachea position), Breathing (lung fields), Circulation (heart size and vasculature), Diaphragm (position and shape), and Everything else (bones, soft tissues) 1. When examining lung fields, compare side to side for symmetry and look for abnormal opacities that appear as white areas against the normally dark lung fields. Heart size is normally less than half the thoracic width, and it is essential to note that significant LV dysfunction may be present without cardiomegaly on the chest X-ray, as stated in the 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure 1. This systematic approach ensures comprehensive evaluation and helps identify both obvious and subtle abnormalities that might indicate disease processes like pneumonia, heart failure, pneumothorax, or masses. In the context of heart failure, a chest X-ray may show pulmonary venous congestion or oedema, and is more helpful in the acute setting than in the non-acute setting 1. However, it is crucial to remember that a chest X-ray is of limited use in the diagnostic work-up of patients with suspected heart failure, and computed tomography (CT) of the chest is currently the standard of care for identifying alternative pulmonary explanations for a patient’s symptoms and signs 1.
From the Research
Interpreting a Chest Radiograph (X-ray)
To interpret a chest radiograph (x-ray), a standardized and systematic approach is necessary to review the image and collect all relevant information [ 2 ]. This approach involves examining various structures, including:
- Soft tissue
- Bones
- Pleura
- Mediastinum
- Lung
- Heart
- Pulmonary circulation
- Hili
Technical Considerations
Technical factors and the position of the patient should also be considered when interpreting a chest x-ray [ 2 ]. Additionally, advancements in digital detection systems and computer processing of images have improved diagnostic capabilities [ 3 ].
Diagnostic Capabilities
Chest x-ray radiographic imagery enables earlier and easier lung disease diagnosis [ 4 ]. Deep learning methods, such as transfer learning techniques, can be used to classify lung diseases on chest x-ray images, improving the efficiency and accuracy of computer-aided diagnostic systems [ 4 ]. Dual-energy, dual-exposure systems have also been implemented, allowing for improved detection of pulmonary nodules and coronary atherosclerosis [ 3 ].
Imaging Strategies
The OPTimal IMAging strategy in patients suspected of non-traumatic pulmonary disease at the emergency department: chest X-ray or ultra-low-dose CT (OPTIMACT) study is a randomized trial designed to evaluate the effectiveness of replacing chest X-ray with ultra-low-dose chest computed tomography (ULD chest CT) in the diagnostic work-up of patients suspected of non-traumatic pulmonary disease [ 5 ]. Another study proposed a hemi-diaphragm detection method for postero-anterior (P-A) chest X-ray images based on convolutional neural network (CNN) and graphics [ 6 ].