[Ethanol Instillation for Mediastinal Cyst].

Mediastinal cyst rarely becomes symptomatic due to compression of adjacent organs. In such case, treatment has to be considered. Either surgical extirpation or percutaneous decompression is the treatment of choice. A 53 years old woman who had been diagnosed with intractable epilepsy, mental retardation and Chilaiditi syndrome was admitted to our hospital because of dyspnea and difficulty in conversation. Chest computed tomography (CT) revealed a mediastinal cystic lesion which expanded to the right chest cavity and occupied most of the right chest cavity. That cyst was treated by percutaneous aspiration and ethanol instillation successfully. Ethanol instillation for the symptomatic mediastinal cyst is the treatment of choice in case the surgery is not feasible.