Christina Stevens,Emily S. Misch,Anne Getz,Eric Hink,Adam Terella, Fibrous Dysplasia of the Frontal Sinus Presenting with Periorbital Emphysema Surgical Case Reports 2021 2613-5965 http://dx.doi.org/10.31487/j.SCR.2021.03.10 https://www.sciencerepository.org/fibrous-dysplasia-of-the-frontal-sinus-presenting-with-periorbital-emphysema_SCR-2021-3-110 Abstract: Fibrous dysplasia (FD) is an uncommon non-malignant bony tumor in which normal bone is replaced by disorganized fibro-osseous tissue. It most often involves the femur, ribs, and craniofacial skeleton and is commonly diagnosed in adolescence or early adulthood. Involvement of the paranasal sinuses is rare, and there is a relative paucity of case reports in the literature. Here, we report a case of FD of the frontal sinus in a 22-year-old male initially presenting with acute onset periorbital emphysema after nose-blowing. Radiographic examination revealed an expansile lesion with “ground-glass” appearance. The patient underwent resection and reconstruction by combined endoscopic and external approach with osteoplastic flap by a multidisciplinary team. The diagnosis of FD was confirmed by permanent histopathology. This report reviews the presentation and treatment of FD of the paranasal sinuses and details a combined external and endoscopic approach to resection of the frontal sinus mass.Keywords: Fibrous dysplasia, bony tumor, paranasal sinuses, frontal sinus