Anatomy
What conditions could cause a mediastinal shift?
Pleural effusion
Pneumothorax
Atelectasis
CXR shows loss of border of superior mediastinum. Where is the lesion?
Upper lobes of the lungs
How can you differentiate between R n L Hemidiaphragms?
R- usually higher due to the liver
L- Contains the stomach, it often has a radiolucent air bubble in it.
Which conditions could cause a mediastinal mass to the following directions? Anterior, Middle, Posterior
Anterior- Goiter, thymoma, lymphoma
Middle- esophageal or bronchial carcinomas
Posterior- aortic aneurysm, neurogenic masses related to the spinal column
CXR shows loss of border of right side of heart. Where is the lesion?
Right middle lobe
What is the Cardiothoracic Ratio? What is normal?
Estimate of heart size
In adults, width of the heart should be <1/2 the width of the chest at the level of the diaphragm
Upon full inspiration, the dome of the diaphragm is at the level of the 10th rib. When will normal elevation be expected? What would cause abnormal elevation or flattening?
Normal elevation- late preg., splinting post Sx
Abnormal elevation- Excessive peritoneal fluid such as with ascitis, cirrhosis
Abnormal flattening- conditions that increase lung volume- emphysema, large pleural effusions
CXR shows loss of border of left side of heart. Where is the lesion?
Left upper lobe or lingula
What is a Silhouette Sign? What information does it give us when present?
Is the loss of normal radiographic interface between air and soft tissue.
- interface between lungs and heart
- interface between lungs and diaphragm
It can be used to localize a lesion to a specific lobe of the lung
What are the costophrenic angles? Why would it be blunt instead of pointy?
Pointy indentations between the hemidiaphragm and the adjacent chest wall.
Fluid pushes lung up and results in a blunting of the costophrenic angle
CXR shows loss of border of the right hemidiaphragm. Where is the lesion?
Right lower lobe
What is the Hilum, or "lung root"? How does it look on radiographs?
Where the bronchi, arteries, veins, and nerves enter and exit the lungs.
Looks as a tangle of vessels on either side of the heart
When is it normal/abnormal to see free air below the Hemidiaphragms?
Normal: gastric or bowel gas below the hemidiaphragm, and for 10 days after any abdominal surgery exposing the peritoneal cavity to air.
Abnormal: free air outside the bowel in the peritoneal cavity. Means perforation from cancer, diverticulitis, peptic ulcer, trauma.
CXR shows loss of border of the left hemidiaphragm. Where is the lesion?
Let lower lobe
What is the mediastinum? What does it contain?
The space between the lungs, bounded anteriorly by the sternum, posteriorly by the spine.
Contains the heart, vessels, trachea, esophagus.