[Plain X-ray diagnosis of noncardiogenic edema]

Noncardiogenic edema is pulmonary edema without increased precapillary blood pressure of the lung. The causes of noncardiogenic edema include decreased blood osmotic pressure, increased permeability of basement membrane, and disturbed lymphatic drainage. We describe the plain X-ray findings of noncardiogenic pulmonary edema as they correlate with the pathophysiology of pulmonary water influx from blood vessels into the extravascular space. We discuss certain selected causes of noncardiogenic edema such as ARDS and high altitude, focusing on the differential diagnosis between cardiogenic edema and noncardiogenic edema and the causes of noncardiogenic edema.