Abstract: Objective To explore the surgical methods and clinical efficacy of an endoscopic transnasal maxillary approach for removing maxillary bone cysts. Methods A retrospective analysis was performed, which included 21 patients with maxillary cysts who underwent endoscopic surgery in our department between March 2014 and April 2019. In all cases, the wall of the maxillary bone cyst protruded into the maxillary sinus. According to an imaging examination such as a computed tomography(CT)scan, the size, range of the cyst, and the relationship between the cyst and each wall of the maxillary sinus were determined. Two surgical approaches were performed. The first approach was through the natural opening of the maxillary sinus. The other approach was through the pre-lacrimal recess, in combination with the first approach. The cyst walls protruding into the maxillary sinus were removed as thoroughly as possible so that the cyst and maxillary sinus could be fused into a common cavity, and a drainage channel was established between the cyst-maxillary sinus and the nasal cavity. Results All patients were followed up for 6 to 24 months after the operation. The mucosae of the operative cavities were well epithelialized. Nasal and facial symptoms disappeared or were significantly relieved. The drainage of the capsule cavity and maxillary sinus was smooth. There was no recurrence in all cases. Conclusions Removal of maxillary bone cysts using a transnasal maxillary approach was reliable and established a smooth drainage channel for the cyst and the maxillary sinus. Additionally, the postoperative cavity could be easily observed. Compared with the traditional approach, it is less traumatic, and results in a quicker recovery time, and lower recurrence rate. These results are in line with other minimally invasive surgeries and show that the technique is worthy of clinical promotion.

Key words: Maxillary bone cyst, Endoscopic surgery, Pre-lacrimal recess approach