cxr Flashcards
from geeky medics
List the steps of going through an xray
- Confirm details
- Asses Image quality (RIPE)
- CXR Interpretation (ABCDE)
What does RIPE stand for?
Rotation
Inspiration
Projection
Exposure
What does ABCDE stand for?
Airway Breathing Cardiac Diaphragm Everything else
How do you asses rotation?
The medial aspect of each clavicle should be equidistant from the spinous processes
The spinous processes should also be in vertically orientated against the vertebral bodies
How do you asses inspiration?
5-6 anterior ribs
The lung apices
Both costophrenic angles
Lateral rib edges should be visible
How do you asses projection?
AP vs PA film
Tip- if there is no label, then assume it’s a PA. Also, if the scapulae are not projected within the chest, it’s PA.
How do you asses exposure?
Left hemidiaphragm visible to the spine and vertebrae visible behind heart
List the things you should interpret for AIRWAYS
Trachea
Carina and Bronchi
Hilar structures
How do you asses the trachea?
The trachea is normally located centrally or just slightly off to the right
If the trachea is deviated, look for anything that could be pushing or pulling at the trachea.
Also inspect for any paratracheal masses/lymphadenopathy
What do abnormal tracheal deviation findings mean?
Pushing of trachea – e.g. large pleural effusion / tension pneumothorax
Pulling of trachea – e.g. consolidation with lobar collapse
Rotation of the patient can give the appearance of a deviated trachea, so as mentioned above, check the clavicles to rule out rotation as the cause.
How do you asses the carina and bronchi?
The carina is located at the point at which the trachea divides into the left and right main bronchus.
On a good quality CXR this division should be visible and is an important landmark when assessing nasogastric tube placement, as the NG tube should bisect the carina if it is correctly placed
Which bronchus is wider?
The right main bronchus is generally wider, shorter and more vertical than the left main bronchus. As a result it is more common for inhaled foreign objects to become lodged here (as the route is more direct).
How do you asses hilar structures?
The hilar consist of the main pulmonary vasculature and the major bronchi.
The hilar are usually the same size, so asymmetry should raise suspicion of pathology
What do bilaterally symmetrical enlarged hila mean?
Associated with sarcoidosis.
What do unilaterally asymmetrical enlarged hila mean?
Underlying malignancy
List the things you need to asses BREATHING
Lungs
Pleura
How do you asses the lungs?
Inspect the lungs:
When looking at a CXR we divide each of the lungs into 3 zones, each occupying 1/3 of the height of the lung.
What does shadowing mean?
Increased airspace shadowing in a given area of the lung field may suggest pathology (e.g. consolidation / malignant lesion).
What does absence of lung markings mean?
Suspect pneumothorax
How do you asses the pleura?
The pleura are not normally visible in healthy individuals, unless there is an abnormality such as pleural thickening.
Inspect the borders of each of the lungs to ensure lung markings extend all the way to the edges of the lung fields
Fluid (hydrothorax) or blood (haemothorax) can also accumulate in the pleural space, causing an area of increased opacity or a combination of both a pneumothorax and fluid
List the things you should asses for CARDIAC
Asses heart size
Asses heart borders
How do you asses heart size
In a healthy individual the heart should occupy no more than 50% of the thoracic width (e.g. a cardiothoracic ratio of <0.5).
This rule only applies to PA chest x-rays (as AP films exaggerate heart size), so you should not draw any conclusions about heart size from an AP film.
List a few reasons that can cause cardiomegaly
Cardiomegaly can occur for a wide variety of reasons including valvular disease, cardiomyopathy, pulmonary hypertension and pericardial effusion.
How do you asses heart borders?
The right atrium makes up most of the right heart border.
The left ventricle makes up most of the left heart border.
What does loss of definition of heart borders indicate?
Loss of definition of the right heart border is associated with right middle lobe consolidation
Loss of definition of the left heart border is associated with lingular consolidation
List the things you need to look at to asses the DIAPHRAGM
Diaphragm
Costophrenic angles
How do you asses the diaphragm?
The right hemi-diaphragm is in most cases higher than the left in healthy individuals (as a result of the underlying liver).
The stomach underlies the left hemi-diaphragm and is best identified by the gastric bubble located within it.
The diaphragm should be indistinguishable from the underlying liver in healthy individuals on an erect CXR
What does it mean when you can distinguish the liver from the diaphragm?
PNEUMOPERITONEUM - free gas is present (often as a result of bowel perforation), air accumulates under the diaphragm causing it to lift and become visibly separate from the liver
Which (niche) condition can give the false appearance of free air under the diaphgram?
Chilaiditi syndrome:
Which involves the colon becoming positioned between the liver and the diaphragm resulting in the appearance of free gas under the diaphragm (because the bowel wall and diaphragm become indistinguishable due to their proximity)
How do you asses costophrenic angles?
In a healthy individual the costo-phrenic angles should be clearly visible on a normal CXR as a well defined acute angle.
What does costophrenic blunting indicate?
Can suggest the presence of fluid or consolidation in the area.
Costophrenic blunting can also occur secondary to lung hyperinflation (seen in diseases such as COPD) as a result of diaphragmatic flattening and subsequent loss of the acute angle.
List the things you asses at EVERYTHING ELSE
Mediastinal contours
Bones
Soft tissues
Tubes/valves/pacemakers/lines
How do you asses mediastinal contours? (2 things)
Aortic knuckle
Aorto-pulmonary window
How do you asses aortic knuckle?
Left lateral edge of the aorta as it arches back over the left main bronchus.
Loss of definition of the aortic knuckles contours can be caused by an aneurysm.
How do you asses the aorto-pulmonary window?
The aorto-pulmonary window is a space located between the arch of the aorta and the pulmonary arteries.
This space can be lost as a result of mediastinal lymphadenopathy (e.g. malignancy).
How do you asses bones?
Inspect the visible skeletal structures looking for any abnormalities (e.g. fractures / lytic lesions).
How do you asses soft tissues?
Inspect the soft tissues for any obvious abnormalities (e.g. large haematoma).
How do you asses tubes/valves/ pacemakers/lines?
Tubes – nasogastric tubes are something you’ll often be asked to assess on a chest x-ray to confirm it is safe for feeding
Lines (e.g. central line / ECG cables).
Artificial valves (e.g. aortic valve replacement).
Pacemaker (often located below the left clavicle).
What are the review areas?
Lastly, before completing your assessment, always ensure you’ve looked at the ‘Review areas’ which are:
Lung apices Retrocardiac Behind the diaphragm Peripheral lungs Hilar
This ensures you’ve comprehensively assessed the x-ray and minimises the risk of missing subtle pathology (e.g. a small nodule).
