**1. Introduction**

Aneurysmal bone cyst (ABC) is an uncommon cystic vascular lesion [1] that is rapidly expanding and locally destructive. It is found mostly during childhood and adolescence and is more common in females [2]. The ABC lesion typically involves the long tubular bones with approximately 3–12% presented in the head and neck region [3] and the most common site being the mandible [4]. It has been reported to arise from the sino-nasal cavity, but involvement of the ethmoid sinuses is extremely rare [3]. ABC may be found in the presence of other benign bone lesions such as non-ossifying fibroma, giant-cell granuloma, fibrous dysplasia, and fibromyxomas [1]. The rarity of this disease in the head and neck region as well as the high risk of recurrence of the lesion makes it interesting and challenging to the head and neck surgeons to deal with such pathology.
