Entirely endoscopic resection of a complicated juvenile psammomatoid ossifying fibroma of the paranasal sinusitis: Case report and review of the literature.

Introduction: Juvenile ossifying fibroma (OF) is a benign fibro-osseous tumor, affecting the bones of the face. It's locally very aggressive, with a strong tendency to recur. We report a case of a juvenile psammomatoid ossifying fibroma (JPOF) complicated with exophthalmos undergoing an entirely endoscopic resection.

Clinical Presentation: A 14-years-old, young woman presented with a 7 months history of headache and right chronic tearing complicated with exophthalmos. Nasal endoscopy revealed a polylobed mass filling the right nasal cavity, the ophthalmic examination showed an isolated exophthalmos. CT scan revealed a well-limited benign mass covered by a thick shell of bone, pushing out the orbital lamina papyracea responsible for a grade 1 exophthalmos. On the facial MRI, we excluded intracranial or intraorbital involvement. A biopsy of the mass describes a psammomatoid juvenile ossifying fibroma. The patient underwent endoscopic transnasal approach with image-guided neuro-navigation system.

Clinical Discussion: JPOF is an aggressive variant of ossifying fibroma occurring predominantly in children with a predilection for the paranasal sinuses. CT scan images show a characteristic well-limited benign expansile mass covered by a thick shell of bone, but sometimes it's mistaken for a mucocele. MRI helps with excluding intracranial or intraorbital involvement. Endonasal endoscopic approaches have been increasingly used and it tends to become the new standard of care.

Conclusion: Treatment consists of complete surgical removal; incomplete resection is associated with a high local recurrence rate. Clinician should keep in mind the need for clinical and radiological follow-up for many years.