Spontaneous pneumomediastinum due to achalasia: an unusual but benign cause.

Pneumomediastinum is usually first identified radiographically in the emergency department. Distinguishing benign from more ominous causes, such as esophageal rupture, is imperative, particularly in the setting of associated esophageal disease. We describe a case, with correlative imaging, of spontaneous pneumomediastinum as the initial presentation of achalasia. A general discussion of spontaneous pneumomediastinum is also provided, including the pathophysiology, precipitating and predisposing factors, clinical manifestations, role of radiology in the diagnosis as well as the radiographic signs.