MORE THAN 80 years ago Politzer1 accurately described the accumulation of clear fluid in the middle ear as a clinical entity. Many articles describing this condition have appeared since that time, but only in the past few years has attention been directed toward investigation of the causative factors and the effective treatment. Interest in this entity arose from the relative frequency with which we encountered it in the past three years. Our early experiences with this condition, which proved very obstinate in some instances, led to a thorough review of the literature in an attempt to determine the causes and the proper treatment. There appeared to be a wide range of possible causes, a lack of unity in methods of treatment, improper diagnosis in many cases, and numerous synonyms for the disease, all indicating the existing confusion. For these reasons, data and a review of the literature from 1940