Case 9
History
The patient is a 20-year-old male status post gunshot wound to the chest.
PA chest film demonstrates a right upper lobe mass
abutting the pleural surface with associated metallic
bullet fragments.
A follow-up chest film seventy two hours later shows
the mass has cavitated.
Diagnosis
Pulmonary Laceration.
Findings
Lungs have a remarkable ability to tolerate a penetrating injury and blunt trauma without long term residual effects. Bleeding and air leakage result from any penetrating lung injury. The physical force ruptures alveolar tissue, and recoil of elastic lung parenchyma leaves a spherical cystic lesion. Their presence may initially be masked by associated hematoma and contusion. These traumatic cysts are not lined by an epithelium but are surrounded by fibrous tissue and therefore are more accurately peeudocysts.
Traumatic cysts may be single or multiple, unilocular or multifocal, and ranging from ovoid to spherical in shape. They most often range from two to 14 cm in diameter and are thin walled. Location is dependent on the site of injury although non-penetrating injury traumatic cysts are almost always subpleural. The majority of patients are asymptomatic, although occasionally a cyst may become infected. Hemoptysis is a rare complication secondary to emptying of the pulmonary hematoma into the bronchial tree.
