Dermoid Cyst of the Floor of the Mouth: Diagnostic Imaging Findings

Abstract

Dermoid cysts of the floor of the mouth are rare, accounting for 11% of all dermoid cysts in the head and neck region. We report a case of a dermoid cyst of the floor of the mouth in a 12-year-old boy investigated with ultrasonography, magnetic resonance imaging (MRI), and non-enhanced computed tomography (CT) scans. The lesion contained free calcified corpuscles (i.e., the "sack of marbles" sign) considered pathognomonic for a dermoid. Diagnostic imaging may allow diagnosis of a dermoid of the floor of the mouth and plays a pivotal role in depicting the anatomic location of a cyst, thus guiding the surgeon for an optimal surgical approach.