Functional endonasal surgery (FES) represents an effective method in the treatment of chronic rhinosinusitis and nasal polyposis. The succes rate of FES is reported as 76–98% in the literature. The revision FES is necessary in 10–18% of primary surgical procedures. In presented paper anatomic findings are evaluated in 28 patients who underwent revision FES. These findings were compared with accessible documentation about previous operations. The most frequent finding was incomplet anterior ethmoidectomy in 57.1% followed by incomplete posterior ethmoidectomy and lateralization of middle turbinate (both in 28.5%). In one fourth of patients failure of frontonasal connection was observed. In 21.4% were presented remnant of uncinate process and middle meatal antrosthomy stenosis. Almost one half of patients had a recurrence of nasal polyposis. Less frequent findings were residual Haller’s cells and concha bullosa. During revision FES procedures one complication occurred – hematoma of eyelids which has resorbed without any sequelas. The technique of primary endonasal surgical procedure is important factor which also determinates efficacy of treatment. Non-radical procedure giving rise to areas with poor ventilation and drainage, especially in ethmoid cells, resulting in risk of persistent or recurrent inflammation and can lead to development of mucocele.

        Key words: revision endonasal surgery, chronic rhinosinusitis, nasal polyposis, mucocele.