Correct!
2. Basilar ground-glass densities and fibrosis with multiple cysts

The CT scan shows multiple cysts in the basilar areas of the lung (Figure 3).

Figure 3. Close up of thoracic CT scan in lung windows showing multiple cysts (arrows).

A number of lesions can be confused with lung cysts (Table 1).

Table 1. Lung lesions that can be confused with lung cysts.

• Emphysema – Areas of emphysema appear as polygonal or rounded low-attenuation areas that lack walls. A bleb is a type of subpleural bulla; the term bleb is now discouraged.
• Honeycombing – Honeycombing appears as clustered hypolucent areas ranging in diameter from 0.3 to 1.0 cm (but occasionally as large as 2.5 cm), with well-defined, often thick walls
• Bronchiectasis – Bronchiectatic cysts (also known as "cystic bronchiectasis") can be differentiated from cystic lung disease based on their continuity with an airway, tendency to form clusters, and associated findings of tram lines and signet or Cabochon ring sign.
• Cavitary lung disease – Pulmonary cavities are typically thick-walled (>4 mm) gas-filled spaces often within an area of consolidation, mass, or nodule and may be filled with other contents in addition to air.
• Pneumatoceles – Pneumatoceles are a type of thin-walled parenchymal cyst that are typically asymptomatic and often disappear following resolution of the inciting event.

Which of the following are true regarding cystic lung disease? (Click on the corect answer to be directed to the sixth of eight pages)

1. Birt-Hogg-Dubé syndrome is associated with skin fibrofolliculomas in most cases
2. Lymphangioleiomyomatosis (LAM) is a disorder that almost exclusively affects women
3. Pulmonary Langerhans cell histiocytosis (PLCH) is associated with current or former cigarette smoking
4. 1 and 3
5. All of the above

Home/Pulmonary