Case 25

Section 1

Look at images 1 and 2.

Image 1

Describe the parenchymal abnormality and its anatomic distribution.



Image 2


Section 2

Find a cluster of centrilobular lucencies in the left lung of image 1 above.

Find 2 clusters of centrilobular lucencies in the right lung of image 2 above.

Section 3

Gross Appearance: Slice of Dried Lung

This picture of the mid right lung shows holes surrounded by normal lung. These holes were more prominent in the upper, than lower, portions of lung. Also note a more diffuse enlargement of air spaces (middle of the picture) along the fissure between the upper and middle lobes.

Find 3 holes. Note that some of the holes have delicate strands across them.

Find the region of diffuse enlargement of air spaces adjacent to the fissure. What does it represent?



Section 4

Histologic Features

This hole replaces most centrilobular structures, remnants of which appear as a central fibrotic focus with small vessels. This fibrotic focus corresponds to the tiny central densities in the lucencies on the HRCT. Adjacent alveoli are almost normal.

Find the centrilobular hole.

Find some normal alveoli.

Compare the histologic distribution of disease in this picture with that in Case 24. (Use the "back" button in the menu bar to return.)


Differential diagnosis of multiple parenchymal lucencies on HRCT: The HRCT findings in this case are characteristic of centrilobular emphysema. Multiple, rounded lucencies can also be seen in cystic lung diseases including Langerhans' cell histiocytosis, lymphangioleiomyomatosis, cystic bronchiectasis, and honeycombing.

Histologic differential diagnosis: This lesion is centrilobular emphysema, which is an incidental finding on lung biopsy of smokers. Other diseases should be sought. Langerhans' cell histiocytosis may occur with this lesion in a smoker. Lymphangioleiomyomatosis may cause similar cysts, and can be diagnosed if typical nodules of smooth muscle are present.

Diagnosis: Centrilobular emphysema

Diagnostic features of centrilobular emphysema on HRCT

Comment: Centrilobular emphysema differs from cystic lung disease in two ways. First, lung cysts contain air and no parenchyma, and the lucencies will appear as dark as air in the trachea or bronchi. However, at times the degree of lung destruction in emphysema can be so severe as to appear as dark as air in the trachea (see below). Second, lung cysts usually have visible walls of varying thickness. Foci of emphysema characteristically have no visible wall, although at times a thin wall may be seen.

Other Types of Emphysema

The image below shows examples of all types of emphysema.

Find 2 bullae.

Find an area of panlobular emphysema.

Find an area of centrilobular emphysema.

Find an area of paraseptal emphysema.

F = the major fissure of the right lung

Note the architectural distortion of the fissure caused by the bullae.




Table of Contents































Numerous small, rounded lucencies are seen throughout the lungs. The distribution is predominantly centrilobular; i.e., they are evenly spaced and near the size of a lobule. They often have a tiny central density. Note that the lucencies are not quite so dark as air in the trachea.





























































Diffuse enlargement of air spaces adjacent to the fissure






























Centrilobular hole





























Example of normal alveoli
































It represents paraseptal emphysema, which differs from both panlobular and centrilobular types by its location along the pleura.





























Cluster of centrilobular lucencies
































Cluster of centrilobular lucencies



























































Centrilobular emphysema






























Panlobular emphysema






























Paraseptal emphysema