OPTICC trial randomly assigns patients who do not appear to have any symptoms or problems from their occult pneumothorax to either having a standard chest tube or to being watched. The term "occult pneumothorax" (OPTX), describes a pneumothorax (PTX) that while not suspected on the basis of either clinical examination or plain radiograph, is ultimately detected with thoraco-abdominal computed tomograms (CT). read more...