Epidemiological studies have shown that up to 80% of all pre-school children develop Eustachian tube dysfunction with middle ear effusion and corresponding conductive hearing loss. The therapy of choice for hyperplastic adenoids is adenoidectomy, often in combination with paracentesis. The objective of this study was to determine whether regular middle ear aeration (Otovent-system) could obviate the need for paracentesis. To this end treatment of 146 children from four to ten years old was conducted within the guidelines of a study protocol. In one group of children, Otovent-supported middle ear aeration was carried out before and after adenoidectomy. In the control group, adenoidectomy was followed by paracentesis. Parents and children were then assigned to follow-up treatment. As additional supportive therapy, children in both groups received decongestant nose drops and a mucolytic agent for a period of 2 weeks. The success of the treatment was evaluated by tympanometry, tone-wave audiometry and ear microscopy. The patients were followed-up at intervals of two and four weeks after the initiation of treatment. The results show that within the study time frame, Otovent treatment compares well to paracentesis. In summary, regular Otovent-supported aeration of the middle ear in many cases can be an alternative to paracentesis.