The authors analyze a group of patients with mucocele and pyocele of the paranasal sinuses. Most frequently the frontal sinus was affected and in particular the olfactory sinuses (15 patients), less frequently the posterior olfactory sinuses and the wedge-shaped sinus (10 patients) and least frequently the maxillary sinus (6 patients). In 17 mucocele was involved, in 14 instances pyocele. In 80.7%, i.e. 25 patients it was primary disease - caused by inflammation, congenital deformities and abnormalities of the orifice of the paranasal cavity. All patients were operated - 15 by the rhinoendoscopic technique, 6 by a combined approach (rhinoendoscopically and by the classical approach), 10 by the classical approach. The follow up period of the patients is 3 months to 10 years. In 27 instances the condition was resolved by a single operation. A relapse occurred in four patients. Successful cure after two operations was recorded in two patients. In one patient we do not have the results of long-term follow up. For assessment of diagnosis CT and rhinoendoscopy were most important.

        Key words: mucocele, pyocele of the paranasal sinuses, rhinoendoscopic surgery.