1. Ali Jassim Alhashli www.alhashli.com
Kingdom of Bahrain Arabian Gulf University College of Medicine and Medical Sciences
Unit II – Problem 4 – Radiology
CXR Interpretation + Obstructive Lung Diseases
Ali Jassim Alhashli

2. Chest Radiography CXR interpretation:
Make sure of patient’s name, age and CPR.
You have to known right and left sides of chest radiograph by knowing:
Where is the apex of the heart.
Locating stomach bubble.
Knowing the shape of the diaphragm (more elevated on the right side due to the presence of the liver).
Then, you have to known the projection of chest radiograph:
Is it antero-posterior (usually written and the heart shadow becomes larger).
OR postero-anterior (standard).
Systemic approach in interpreting a CXR (RIP-ABCD’S):
RIP: Rotation, Inspiration, Penetration.
ABCD’S: Airway, Bilateral lung fields, Cardiac shadow, Diaphragm, Soft tissues and everything else. PA AP

3. Chest Radiography Rotation:
The distance between each clavicle and the spinous process has to be equal.
Inspiration:
Patient must be examined in full inspiration which is equal to:
8-10 posterior ribs.
5-7 anterior ribs.
Penetration:
The thoracic spine disc spaces should be barely visible through the heart but bony details of the spine are not usually seen.

4. Chest Radiography Airway:
Look to the trachea and make sure it is central (no deviation to the right or left) and patent (no stenosis). In the radiograph attached, the trachea is deviated toward the right side but it is patent.
Bilateral lung fields:
Divide the lung to 3 zones:
Upper zone: apex – 2nd costal cartilage.
Middle zone: 2nd – 4th costal cartilages.
Lower zone: 4th – 6th costal cartilages.
Make sure there is equal radiolucency of both lung fields. If there is an opacity, describe:
Location.
Size.
Homogenous or heterogenous.
Shape and borders.
Make sure there are no infiltrates or opacities.
Look for vascular markings (normally: vessels in bases are more than in apices).

5. Chest Radiography

6. Chest Radiography Cardiac shadow:
Site: is the heart located on the left or right.
Size: normally the largest diameter of the heart must be less than half of the largest diameter of the thorax (transothoracic diameter).
Borders: are they well-defined (Silhouette-margins should be sharp).

7. Chest Radiography

8. Chest Radiography Tension pneumothorax:
Patient will complain of: chest pain and dyspnea.
Chest x-ray shows: darker lung filed (indicating presence of air), shift of trachea and mediastinum away from affected side and collapse of the lung at the affected side.
Physical examination:
Palpation: decreased chest wall expansion at the affected side with decreased tactile fremitus.
Percussion: hyperresonance.
Auscultation: decreased air entry at the affected side with decreased vocal resonance.

9. Chest Radiography Diaphragm:
Diaphragm has to be smooth, clear and curved downwards.
Costodiaphragmatic angles should be sharp and clear.
Right hemidiaphragm is normally 2-3 cm higher that the left hemidiaphragm (due to presence of the liver).
Make sure there is no free air under the diaphragm (otherwise this indicated pneumoperitoneum).
Soft tissues and everything else:
Look for swelling of soft tissues or subcutaneous air (e.g. surgical emphysema).
Look for fractures, lytic bone lesions and devices/instruments.

10. CXR of Obstructive Lung Disease (COPD and Asthma)
In patients with COPD or asthma there are signs of hyperinflation of lungs detected by chest x-ray. These signs include the following:
Flattened hemidiaphragms.
More than 6 anterior or 10 posterior in the mid-clavicular line at the lung diaphragm level.
Hyperlucent lungs (less bronchovascular markings per cm2).

11. CT-scan of Obstructive Lung Disease (COPD and Asthma)