Stages of Nasal Mucosal Transitional Course after Functional Endoscopic Sinus Surgery and Their Clinical Indications

<i>Objective:</i> We aimed to explore the transitional process of sinus cavity mucosa after functional endoscopic sinus surgery (FESS) and divide it into different stages. <i>Method:</i> The morphological characteristics of sinus cavity mucosa after FESS were continuously observed. <i>Results:</i> Over 90% of the nasal and sinus cavities got clean within 1–2 weeks, over 80% of the operative cavities experienced a reaction to mucosa removal or regenerative diseases within 3–10 weeks, such as mucosal edema, vesicles, granulation tissue, mini-polyps, fibrous hyperplasia and adhesion, which competed against the mucosa epithelialization process. After careful treatment, 90% of the nasal and sinus cavities finished epithelialization, and 60% of them completed epithelialization within 11–14 weeks after operation. <i>Conclusion:</i> The recovery process of mucosa after FESS can be divided into 3 stages: the stage of clean operative cavity, the stage of mucosal transition and the stage of complete epithelialization. Proper management at the 3 stages is very essential to the whole curable effect of FESS.