IMAGING - Thoracic Ultrasound Flashcards
How should a normal lung appear on ultrasound?
A normal lung is gas filled and thus will have parallel reverberation (A lines) which move with respiration. Furthermore, the ribs will cast a strong shadow over the reverberation
How should a normal pleural appear on ultrasound?
A normal pleura should appear as a smooth hyperechoic line which glides with respiration
How does a ‘wet’ lung appear on ultrasound?
A ‘wet’ lung has echogenic artifacts extending from the pleural line, known as B lines
How many B linesd would be considered normal in a dog?
Up to two B lines
What are the key signs of lung consolidation on ultrasound?
Normal lung parenchyma is gas filled which will result in reverberation lines, preventing the assessment of the normal lung architecture. However, when there is lung consolidation, the air is replaced by soft tissue/fluid, resulting in the lung appearing homogenously echogenic with visible pulmonary vessels - the lung will resemble the liver. Furthermore, lung consolidation is associated with the ‘shred’ sign
What is the ‘shred’ sign on ultrasound?
The ‘shred’ sign is a sign of lung consolidation. The lung with appear hypoechoic, accompanied by an irregular border in contact with normal, aerated lung
What is the costal ‘step’ sign on ultrasound?
The costal ‘step’ sign on ultrasound is an irregular pleural line which is indicative of thoracic wall injury (i.e rib fractures)
How do transudate pleural effusions appear on ultrasound?
Transudate pleural effusions appear as anechoic on ultrasound
How do modified transudate pleural effusions appear on ultrasound?
Modified transudate pleural effusions appear as hypoechoic on ultrasound
How do exudate pleural effusions appear on ultrasound?
Exudate pleural effusions appear as hyperechoic on ultrasound
How do you differentiate between a pleural and pericardial effusion?
To differentiate between a pleural and pericardial effusion, assess the pericardium. The pericardium is represented by a hyperechoic line around the myocardium, if there is no seperation between the pericardium and myocardium, then it is not a pericardial effusion
When is ultrasound the most useful when it comes to assessing thoracic masses?
Ultrasound is particularly useful if the mass is located in close contact with the thoracic wall and if they have already been identified using radiography. Ultrasound can also be used to guide fine needle aspirates (FNAs) of the mass to avoid accidentally hitting large vessels and the heart
When is colour flow doppler useful when assessing thoracic masses?
Colour flow doppler allows for the assessment of blood flow within the mass
How should your patient be positioned for echocardiography?
The patient should be positioned in right lateral recumbency and the probe should be placed over the right beat on the right side of the chest
What is the conventional orientation for the short axis views of the heart?
For the short axis views, the left atrium will be on the left side of the screen