Abstract: Objective To analyze the clinical features of juvenile ossifying fibroma in the nasal cavity and sinuses and discuss the treatment. Methods From May 2015 to December 2017, 6 children(4 boys, 2 girls)with ossification fibroma of the nasal cavity and paranasal sinuses were selected with ages ranging from 2 months to 12 years 6 months, with a median age of 6 years and 2 months. The tumors occurred in the maxillary sinus(1 case), ethmoid sinus(3 cases), sphenoid sinus(1 case)and frontal sinus(1 case). All the children were treated via surgery. One case showed the involvement of the optic nerve in the tumor. Nasal endoscopy-mediated partial resection of the tumor was performed to preserve the childs eyesight. Six months after the operation, the optic nerve was found to be involved in the optic nerve and the skull base was extensively involved. The second partial resection of the tumor was performed under nasal endoscope after recurrence of the tumor involving a wider area, 6 months after the operation. During the third operation, the right nasal incision combined with nasal endoscope-mediated partial resection of the ossification fibroma of nasal sinuses was performed. All other children underwent endoscopic resection of tumors, except for one, whose age was 2 months and was not examined via computed tomography(CT). Metronic FUSION ENT Image Guidance System-based electromagnetic navigation technique was used to locate the tumor margin. Another case was treated with interventional angiography and embolization 1 day before nasal endoscopy because the tumor was located in the sphenoid sinus and had definite nourishing vessels. All the patients were followed up with regularly using nasal endoscopy and sinus CT. Results The pathological classification of 6 cases was as follows: sandy gravel in 5 cases and trabecular shape in 1 case. The average follow-up time was 2.2 years. There was one incidence of recurrence for which partial resection of the tumor was performed, and the patient survived with the tumor after the operation. No recurrence or complications were found in the other children during the follow-up period, and the primary symptoms were effectively alleviated. Conclusion Osteofibroma of the nasal cavity and paranasal sinuses has the characteristics of invasive growth and easy recurrence after operation, and surgery is the only effective treatment. Endoscopic sinus surgery with image navigation has been deemed suitable for children.

Key words: Nasal sinuses, Juvenile ossifying fibroma, Pediatrics, Surgical procedures, operative, Image navigation system