2.5 Basic Thoracic CT Mediastinal Anatomy

Question 1

Label the major structures in this axial CT image of the thoracic cavity.

Answer 1

This is a post-contrast image is located about halfway down the chest.

1. Note the SVC is brighter than the aorta as the contrast was administered venously and tends to collect in the vena cava first.
2. The ascending portion of the aorta is next to the SVC. The descending portion of the aorta is next to the vertebral column.
3. Note the pulmonary trunk branching into R and L pulmonary arteries - note the bifurcation of the L pulmonary artery seen - this is the area of the hilum.

Question 2

Label the major structures in this coronal CT image of the thoracic cavity.

Answer 2

1. LV - thick muscle, which is normal
2. Contrast is more bright in R atrium
3. Pulmonary artery seen, also the aorta seen branching out from the LV
4. Liver is also present

Question 3

Label the major structures in the lung window of the coronal CT of the thoracic cavity.

Answer 3

Question 4

Label the major structures in the lung window of the axial CT of the thoracic cavity.

Answer 4

Note that the upper lobes of the lung are also anterior.

You cannot see the minor fissure in this particular image, but you could see it by scrolling. It is a little more difficult to see in the axial view.

Question 5

Compare the anatomy of the R and L lungs on sagittal CT with lung window.

Answer 5

Note the fissures.

These are images from different lungs from different patients. They are positioned so that their ‘backs’ are to each other’ in this image.