Seyyed Mostafa Hashemi - Department of Otorhinolaryngology, Kashani Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Mita Heidarpour - Department of Pathology, Kashani Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Afrooz Eshaghian - Department of Otorhinolaryngology, Kashani Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Peyman Ansari - Department of Radiology, Kashani University of Medical Sciences, Isfahan, Iran.
Maryamsadat Hashemi - General Practitioner, Isfahan University of Medical Sciences, Isfahan, Iran.
Maryam Yaghoobi - Department of Otorhinolaryngology, Kashani Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.
Sohrab Barati - Department of Otorhinolaryngology, Kashani Hospital, Isfahan University of Medical Sciences, Isfahan, Iran.

Introduction: Aneurysmal Bone cysts (ABC) are extremely rare in the head and neck region and even rarer in sinuses.  ABC is a benign multicystic mass that is locally-destructive and rapidly expandable. Hemorrhagic fluid content (like in this case) and septated appearance are the characteristic feature of ABC. Established treatment options for ABCs include sclerotherapy, embolization, radiotherapy, simple curettage, surgical excision, or a combination of methods.   Case Report: In this article, a ۵ year-old boy with a recurrent nasal mass is presented. The patient was finally diagnosed with this rare entity: ABC of the paranasal sinuses. The patient was treated through complete surgical removal.   Conclusion:  ABC can be considered as a rare differential diagnosis of recurrent nasal hemorrhagic mass in a pediatric population.

Aneurysmal Bone Cysts (ABC), Angiofibroma