Pulmonary edema cardiac arrest due to hypoxia. It is a cardinal feature of congestive heart failure. The term edema is from the Greek (oídēma, "swelling"), from οἰδέω (oidéō, "I swell"). The most common symptom of pulmonary edema is difficulty breathing, but may include other symptoms such as coughing up blood (classically seen as pink, frothy sputum), excessive sweating, anxiety, and pale skin. Shortness of breath can manifest as orthopnea (inability to lie down flat due to breathlessness) and/or paroxysmal nocturnal dyspnea (episodes of severe sudden breathlessness at night). These are common presenting symptoms of chronic pulmonary edema due to left ventricular failure.
Berlin's edema and therefore it is not considered a true edema. The choroidal fluorescence in fluorescent angiography is absent. Visual acuity ranges from 20/20 to 20/400. The prognosis is excellent except in case of complications of choroidal rupture, hemorrhage or pigment epithelial damage, but damage to the macula will result in poorer recovery. The outcome can be worsened in the case of retinal detachment, atrophy or hyperplasia. Visual field defects can occur. In late cases cystoid macular edema sometimes develops which can further lead to macular destruction. Commotio retinae is usually self limiting and there is no treatment as such. It usually