In a thoracoscopic resection of mediastinal cysts, aspiration of the cyst c
ontents at the beginning of the procedure is often helpful because it allow
s the cyst to be more easily grasped and manipulated. Spillage of the cyst
contents into the thoracic cavity may, however, occur during aspiration whe
n an ordinary aspiration needle is used. If the cyst contents are infective
, then a subsequent contamination of the thoracic cavity may develop. We th
erefore use a specially designed double-balloon catheter for aspiration to
minimize spillage of the cyst contents into the thoracic cavity. We describ
e herein the usefulness of this aspiration technique.